diff options
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/Makefile | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_internal.h | 3 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_irq.c | 1623 | ||||
| -rw-r--r-- | drivers/gpu/drm/drm_vblank.c | 1645 |
4 files changed, 1670 insertions, 1603 deletions
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index c156fecfb362..acc88942c2e5 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -16,7 +16,7 @@ drm-y := drm_auth.o drm_bufs.o drm_cache.o \ drm_framebuffer.o drm_connector.o drm_blend.o \ drm_encoder.o drm_mode_object.o drm_property.o \ drm_plane.o drm_color_mgmt.o drm_print.o \ - drm_dumb_buffers.o drm_mode_config.o + drm_dumb_buffers.o drm_mode_config.o drm_vblank.o drm-$(CONFIG_DRM_LIB_RANDOM) += lib/drm_random.o drm-$(CONFIG_DRM_VM) += drm_vm.o diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal.h index 3d8e8f878924..ba3f5fb21959 100644 --- a/drivers/gpu/drm/drm_internal.h +++ b/drivers/gpu/drm/drm_internal.h @@ -53,8 +53,9 @@ int drm_name_info(struct seq_file *m, void *data); int drm_clients_info(struct seq_file *m, void* data); int drm_gem_name_info(struct seq_file *m, void *data); -/* drm_irq.c */ +/* drm_vblank.c */ extern unsigned int drm_timestamp_monotonic; +void drm_vblank_disable_and_save(struct drm_device *dev, unsigned int pipe); /* IOCTLS */ int drm_wait_vblank(struct drm_device *dev, void *data, diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index c7debaad67f8..28d736c3fcb4 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -3,6 +3,25 @@ * * \author Rickard E. (Rik) Faith <faith@valinux.com> * \author Gareth Hughes <gareth@valinux.com> + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. */ /* @@ -32,429 +51,15 @@ * OTHER DEALINGS IN THE SOFTWARE. */ +#include <drm/drm_irq.h> #include <drm/drmP.h> -#include "drm_trace.h" -#include "drm_internal.h" #include <linux/interrupt.h> /* For task queue support */ -#include <linux/slab.h> #include <linux/vgaarb.h> #include <linux/export.h> -/* Retry timestamp calculation up to 3 times to satisfy - * drm_timestamp_precision before giving up. - */ -#define DRM_TIMESTAMP_MAXRETRIES 3 - -/* Threshold in nanoseconds for detection of redundant - * vblank irq in drm_handle_vblank(). 1 msec should be ok. - */ -#define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000 - -static bool -drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, - struct timeval *tvblank, bool in_vblank_irq); - -static unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */ - -/* - * Default to use monotonic timestamps for wait-for-vblank and page-flip - * complete events. - */ -unsigned int drm_timestamp_monotonic = 1; - -static int drm_vblank_offdelay = 5000; /* Default to 5000 msecs. */ - -module_param_named(vblankoffdelay, drm_vblank_offdelay, int, 0600); -module_param_named(timestamp_precision_usec, drm_timestamp_precision, int, 0600); -module_param_named(timestamp_monotonic, drm_timestamp_monotonic, int, 0600); -MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)"); -MODULE_PARM_DESC(timestamp_precision_usec, "Max. error on timestamps [usecs]"); -MODULE_PARM_DESC(timestamp_monotonic, "Use monotonic timestamps"); - -static void store_vblank(struct drm_device *dev, unsigned int pipe, - u32 vblank_count_inc, - struct timeval *t_vblank, u32 last) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - assert_spin_locked(&dev->vblank_time_lock); - - vblank->last = last; - - write_seqlock(&vblank->seqlock); - vblank->time = *t_vblank; - vblank->count += vblank_count_inc; - write_sequnlock(&vblank->seqlock); -} - -/* - * "No hw counter" fallback implementation of .get_vblank_counter() hook, - * if there is no useable hardware frame counter available. - */ -static u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe) -{ - WARN_ON_ONCE(dev->max_vblank_count != 0); - return 0; -} - -static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe) -{ - if (drm_core_check_feature(dev, DRIVER_MODESET)) { - struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); - - if (crtc->funcs->get_vblank_counter) - return crtc->funcs->get_vblank_counter(crtc); - } - - if (dev->driver->get_vblank_counter) - return dev->driver->get_vblank_counter(dev, pipe); - - return drm_vblank_no_hw_counter(dev, pipe); -} - -/* - * Reset the stored timestamp for the current vblank count to correspond - * to the last vblank occurred. - * - * Only to be called from drm_crtc_vblank_on(). - * - * Note: caller must hold &drm_device.vbl_lock since this reads & writes - * device vblank fields. - */ -static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe) -{ - u32 cur_vblank; - bool rc; - struct timeval t_vblank; - int count = DRM_TIMESTAMP_MAXRETRIES; - - spin_lock(&dev->vblank_time_lock); - - /* - * sample the current counter to avoid random jumps - * when drm_vblank_enable() applies the diff - */ - do { - cur_vblank = __get_vblank_counter(dev, pipe); - rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false); - } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); - - /* - * Only reinitialize corresponding vblank timestamp if high-precision query - * available and didn't fail. Otherwise reinitialize delayed at next vblank - * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid. - */ - if (!rc) - t_vblank = (struct timeval) {0, 0}; - - /* - * +1 to make sure user will never see the same - * vblank counter value before and after a modeset - */ - store_vblank(dev, pipe, 1, &t_vblank, cur_vblank); - - spin_unlock(&dev->vblank_time_lock); -} - -/* - * Call back into the driver to update the appropriate vblank counter - * (specified by @pipe). Deal with wraparound, if it occurred, and - * update the last read value so we can deal with wraparound on the next - * call if necessary. - * - * Only necessary when going from off->on, to account for frames we - * didn't get an interrupt for. - * - * Note: caller must hold &drm_device.vbl_lock since this reads & writes - * device vblank fields. - */ -static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, - bool in_vblank_irq) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - u32 cur_vblank, diff; - bool rc; - struct timeval t_vblank; - int count = DRM_TIMESTAMP_MAXRETRIES; - int framedur_ns = vblank->framedur_ns; - - /* - * Interrupts were disabled prior to this call, so deal with counter - * wrap if needed. - * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events - * here if the register is small or we had vblank interrupts off for - * a long time. - * - * We repeat the hardware vblank counter & timestamp query until - * we get consistent results. This to prevent races between gpu - * updating its hardware counter while we are retrieving the - * corresponding vblank timestamp. - */ - do { - cur_vblank = __get_vblank_counter(dev, pipe); - rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, in_vblank_irq); - } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); - - if (dev->max_vblank_count != 0) { - /* trust the hw counter when it's around */ - diff = (cur_vblank - vblank->last) & dev->max_vblank_count; - } else if (rc && framedur_ns) { - const struct timeval *t_old; - u64 diff_ns; - - t_old = &vblank->time; - diff_ns = timeval_to_ns(&t_vblank) - timeval_to_ns(t_old); - - /* - * Figure out how many vblanks we've missed based - * on the difference in the timestamps and the - * frame/field duration. - */ - diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns); - - if (diff == 0 && in_vblank_irq) - DRM_DEBUG_VBL("crtc %u: Redundant vblirq ignored." - " diff_ns = %lld, framedur_ns = %d)\n", - pipe, (long long) diff_ns, framedur_ns); - } else { - /* some kind of default for drivers w/o accurate vbl timestamping */ - diff = in_vblank_irq ? 1 : 0; - } - - /* - * Within a drm_vblank_pre_modeset - drm_vblank_post_modeset - * interval? If so then vblank irqs keep running and it will likely - * happen that the hardware vblank counter is not trustworthy as it - * might reset at some point in that interval and vblank timestamps - * are not trustworthy either in that interval. Iow. this can result - * in a bogus diff >> 1 which must be avoided as it would cause - * random large forward jumps of the software vblank counter. - */ - if (diff > 1 && (vblank->inmodeset & 0x2)) { - DRM_DEBUG_VBL("clamping vblank bump to 1 on crtc %u: diffr=%u" - " due to pre-modeset.\n", pipe, diff); - diff = 1; - } - - DRM_DEBUG_VBL("updating vblank count on crtc %u:" - " current=%u, diff=%u, hw=%u hw_last=%u\n", - pipe, vblank->count, diff, cur_vblank, vblank->last); - - if (diff == 0) { - WARN_ON_ONCE(cur_vblank != vblank->last); - return; - } - - /* - * Only reinitialize corresponding vblank timestamp if high-precision query - * available and didn't fail, or we were called from the vblank interrupt. - * Otherwise reinitialize delayed at next vblank interrupt and assign 0 - * for now, to mark the vblanktimestamp as invalid. - */ - if (!rc && in_vblank_irq) - t_vblank = (struct timeval) {0, 0}; - - store_vblank(dev, pipe, diff, &t_vblank, cur_vblank); -} - -static u32 drm_vblank_count(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return 0; - - return vblank->count; -} - -/** - * drm_accurate_vblank_count - retrieve the master vblank counter - * @crtc: which counter to retrieve - * - * This function is similar to @drm_crtc_vblank_count but this - * function interpolates to handle a race with vblank irq's. - * - * This is mostly useful for hardware that can obtain the scanout - * position, but doesn't have a frame counter. - */ -u32 drm_accurate_vblank_count(struct drm_crtc *crtc) -{ - struct drm_device *dev = crtc->dev; - unsigned int pipe = drm_crtc_index(crtc); - u32 vblank; - unsigned long flags; - - WARN(!dev->driver->get_vblank_timestamp, - "This function requires support for accurate vblank timestamps."); - - spin_lock_irqsave(&dev->vblank_time_lock, flags); - - drm_update_vblank_count(dev, pipe, false); - vblank = drm_vblank_count(dev, pipe); - - spin_unlock_irqrestore(&dev->vblank_time_lock, flags); - - return vblank; -} -EXPORT_SYMBOL(drm_accurate_vblank_count); - -static void __disable_vblank(struct drm_device *dev, unsigned int pipe) -{ - if (drm_core_check_feature(dev, DRIVER_MODESET)) { - struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); - - if (crtc->funcs->disable_vblank) { - crtc->funcs->disable_vblank(crtc); - return; - } - } - - dev->driver->disable_vblank(dev, pipe); -} - -/* - * Disable vblank irq's on crtc, make sure that last vblank count - * of hardware and corresponding consistent software vblank counter - * are preserved, even if there are any spurious vblank irq's after - * disable. - */ -static void vblank_disable_and_save(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - unsigned long irqflags; - - assert_spin_locked(&dev->vbl_lock); - - /* Prevent vblank irq processing while disabling vblank irqs, - * so no updates of timestamps or count can happen after we've - * disabled. Needed to prevent races in case of delayed irq's. - */ - spin_lock_irqsave(&dev->vblank_time_lock, irqflags); - - /* - * Only disable vblank interrupts if they're enabled. This avoids - * calling the ->disable_vblank() operation in atomic context with the - * hardware potentially runtime suspended. - */ - if (vblank->enabled) { - __disable_vblank(dev, pipe); - vblank->enabled = false; - } - - /* - * Always update the count and timestamp to maintain the - * appearance that the counter has been ticking all along until - * this time. This makes the count account for the entire time - * between drm_crtc_vblank_on() and drm_crtc_vblank_off(). - */ - drm_update_vblank_count(dev, pipe, false); - - spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags); -} - -static void vblank_disable_fn(unsigned long arg) -{ - struct drm_vblank_crtc *vblank = (void *)arg; - struct drm_device *dev = vblank->dev; - unsigned int pipe = vblank->pipe; - unsigned long irqflags; - - spin_lock_irqsave(&dev->vbl_lock, irqflags); - if (atomic_read(&vblank->refcount) == 0 && vblank->enabled) { - DRM_DEBUG("disabling vblank on crtc %u\n", pipe); - vblank_disable_and_save(dev, pipe); - } - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); -} - -/** - * drm_vblank_cleanup - cleanup vblank support - * @dev: DRM device - * - * This function cleans up any resources allocated in drm_vblank_init. - */ -void drm_vblank_cleanup(struct drm_device *dev) -{ - unsigned int pipe; - - /* Bail if the driver didn't call drm_vblank_init() */ - if (dev->num_crtcs == 0) - return; - - for (pipe = 0; pipe < dev->num_crtcs; pipe++) { - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - WARN_ON(READ_ONCE(vblank->enabled) && - drm_core_check_feature(dev, DRIVER_MODESET)); - - del_timer_sync(&vblank->disable_timer); - } - - kfree(dev->vblank); - - dev->num_crtcs = 0; -} -EXPORT_SYMBOL(drm_vblank_cleanup); - -/** - * drm_vblank_init - initialize vblank support - * @dev: DRM device - * @num_crtcs: number of CRTCs supported by @dev - * - * This function initializes vblank support for @num_crtcs display pipelines. - * - * Returns: - * Zero on success or a negative error code on failure. - */ -int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs) -{ - int ret = -ENOMEM; - unsigned int i; - - spin_lock_init(&dev->vbl_lock); - spin_lock_init(&dev->vblank_time_lock); - - dev->num_crtcs = num_crtcs; - - dev->vblank = kcalloc(num_crtcs, sizeof(*dev->vblank), GFP_KERNEL); - if (!dev->vblank) - goto err; - - for (i = 0; i < num_crtcs; i++) { - struct drm_vblank_crtc *vblank = &dev->vblank[i]; - - vblank->dev = dev; - vblank->pipe = i; - init_waitqueue_head(&vblank->queue); - setup_timer(&vblank->disable_timer, vblank_disable_fn, - (unsigned long)vblank); - seqlock_init(&vblank->seqlock); - } - - DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n"); - - /* Driver specific high-precision vblank timestamping supported? */ - if (dev->driver->get_vblank_timestamp) - DRM_INFO("Driver supports precise vblank timestamp query.\n"); - else - DRM_INFO("No driver support for vblank timestamp query.\n"); - - /* Must have precise timestamping for reliable vblank instant disable */ - if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) { - dev->vblank_disable_immediate = false; - DRM_INFO("Setting vblank_disable_immediate to false because " - "get_vblank_timestamp == NULL\n"); - } - - return 0; - -err: - dev->num_crtcs = 0; - return ret; -} -EXPORT_SYMBOL(drm_vblank_init); +#include "drm_internal.h" /** * drm_irq_install - install IRQ handler @@ -571,7 +176,7 @@ int drm_irq_uninstall(struct drm_device *dev) WARN_ON(drm_core_check_feature(dev, DRIVER_MODESET)); - vblank_disable_and_save(dev, i); + drm_vblank_disable_and_save(dev, i); wake_up(&vblank->queue); } spin_unlock_irqrestore(&dev->vbl_lock, irqflags); @@ -634,1187 +239,3 @@ int drm_legacy_irq_control(struct drm_device *dev, void *data, return -EINVAL; } } - -/** - * drm_calc_timestamping_constants - calculate vblank timestamp constants - * @crtc: drm_crtc whose timestamp constants should be updated. - * @mode: display mode containing the scanout timings - * - * Calculate and store various constants which are later - * needed by vblank and swap-completion timestamping, e.g, - * by drm_calc_vbltimestamp_from_scanoutpos(). They are - * derived from CRTC's true scanout timing, so they take - * things like panel scaling or other adjustments into account. - */ -void drm_calc_timestamping_constants(struct drm_crtc *crtc, - const struct drm_display_mode *mode) -{ - struct drm_device *dev = crtc->dev; - unsigned int pipe = drm_crtc_index(crtc); - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - int linedur_ns = 0, framedur_ns = 0; - int dotclock = mode->crtc_clock; - - if (!dev->num_crtcs) - return; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return; - - /* Valid dotclock? */ - if (dotclock > 0) { - int frame_size = mode->crtc_htotal * mode->crtc_vtotal; - - /* - * Convert scanline length in pixels and video - * dot clock to line duration and frame duration - * in nanoseconds: - */ - linedur_ns = div_u64((u64) mode->crtc_htotal * 1000000, dotclock); - framedur_ns = div_u64((u64) frame_size * 1000000, dotclock); - - /* - * Fields of interlaced scanout modes are only half a frame duration. - */ - if (mode->flags & DRM_MODE_FLAG_INTERLACE) - framedur_ns /= 2; - } else - DRM_ERROR("crtc %u: Can't calculate constants, dotclock = 0!\n", - crtc->base.id); - - vblank->linedur_ns = linedur_ns; - vblank->framedur_ns = framedur_ns; - vblank->hwmode = *mode; - - DRM_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n", - crtc->base.id, mode->crtc_htotal, - mode->crtc_vtotal, mode->crtc_vdisplay); - DRM_DEBUG("crtc %u: clock %d kHz framedur %d linedur %d\n", - crtc->base.id, dotclock, framedur_ns, linedur_ns); -} -EXPORT_SYMBOL(drm_calc_timestamping_constants); - -/** - * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper - * @dev: DRM device - * @pipe: index of CRTC whose vblank timestamp to retrieve - * @max_error: Desired maximum allowable error in timestamps (nanosecs) - * On return contains true maximum error of timestamp - * @vblank_time: Pointer to struct timeval which should receive the timestamp - * @in_vblank_irq: - * True when called from drm_crtc_handle_vblank(). Some drivers - * need to apply some workarounds for gpu-specific vblank irq quirks - * if flag is set. - * - * Implements calculation of exact vblank timestamps from given drm_display_mode - * timings and current video scanout position of a CRTC. This can be called from - * within get_vblank_timestamp() implementation of a kms driver to implement the - * actual timestamping. - * - * Should return timestamps conforming to the OML_sync_control OpenML - * extension specification. The timestamp corresponds to the end of - * the vblank interval, aka start of scanout of topmost-leftmost display - * pixel in the following video frame. - * - * Requires support for optional dev->driver->get_scanout_position() - * in kms driver, plus a bit of setup code to provide a drm_display_mode - * that corresponds to the true scanout timing. - * - * The current implementation only handles standard video modes. It - * returns as no operation if a doublescan or interlaced video mode is - * active. Higher level code is expected to handle this. - * - * This function can be used to implement the &drm_driver.get_vblank_timestamp - * directly, if the driver implements the &drm_driver.get_scanout_position hook. - * - * Note that atomic drivers must call drm_calc_timestamping_constants() before - * enabling a CRTC. The atomic helpers already take care of that in - * drm_atomic_helper_update_legacy_modeset_state(). - * - * Returns: - * - * Returns true on success, and false on failure, i.e. when no accurate - * timestamp could be acquired. - */ -bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, - unsigned int pipe, - int *max_error, - struct timeval *vblank_time, - bool in_vblank_irq) -{ - struct timeval tv_etime; - ktime_t stime, etime; - bool vbl_status; - struct drm_crtc *crtc; - const struct drm_display_mode *mode; - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - int vpos, hpos, i; - int delta_ns, duration_ns; - - if (!drm_core_check_feature(dev, DRIVER_MODESET)) - return false; - - crtc = drm_crtc_from_index(dev, pipe); - - if (pipe >= dev->num_crtcs || !crtc) { - DRM_ERROR("Invalid crtc %u\n", pipe); - return false; - } - - /* Scanout position query not supported? Should not happen. */ - if (!dev->driver->get_scanout_position) { - DRM_ERROR("Called from driver w/o get_scanout_position()!?\n"); - return false; - } - - if (drm_drv_uses_atomic_modeset(dev)) - mode = &vblank->hwmode; - else - mode = &crtc->hwmode; - - /* If mode timing undefined, just return as no-op: - * Happens during initial modesetting of a crtc. - */ - if (mode->crtc_clock == 0) { - DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe); - WARN_ON_ONCE(drm_drv_uses_atomic_modeset(dev)); - - return false; - } - - /* Get current scanout position with system timestamp. - * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times - * if single query takes longer than max_error nanoseconds. - * - * This guarantees a tight bound on maximum error if - * code gets preempted or delayed for some reason. - */ - for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) { - /* - * Get vertical and horizontal scanout position vpos, hpos, - * and bounding timestamps stime, etime, pre/post query. - */ - vbl_status = dev->driver->get_scanout_position(dev, pipe, - in_vblank_irq, - &vpos, &hpos, - &stime, &etime, - mode); - - /* Return as no-op if scanout query unsupported or failed. */ - if (!vbl_status) { - DRM_DEBUG("crtc %u : scanoutpos query failed.\n", - pipe); - return false; - } - - /* Compute uncertainty in timestamp of scanout position query. */ - duration_ns = ktime_to_ns(etime) - ktime_to_ns(stime); - - /* Accept result with < max_error nsecs timing uncertainty. */ - if (duration_ns <= *max_error) - break; - } - - /* Noisy system timing? */ - if (i == DRM_TIMESTAMP_MAXRETRIES) { - DRM_DEBUG("crtc %u: Noisy timestamp %d us > %d us [%d reps].\n", - pipe, duration_ns/1000, *max_error/1000, i); - } - - /* Return upper bound of timestamp precision error. */ - *max_error = duration_ns; - - /* Convert scanout position into elapsed time at raw_time query - * since start of scanout at first display scanline. delta_ns - * can be negative if start of scanout hasn't happened yet. - */ - delta_ns = div_s64(1000000LL * (vpos * mode->crtc_htotal + hpos), - mode->crtc_clock); - - if (!drm_timestamp_monotonic) - etime = ktime_mono_to_real(etime); - - /* save this only for debugging purposes */ - tv_etime = ktime_to_timeval(etime); - /* Subtract time delta from raw timestamp to get final - * vblank_time timestamp for end of vblank. - */ - etime = ktime_sub_ns(etime, delta_ns); - *vblank_time = ktime_to_timeval(etime); - - DRM_DEBUG_VBL("crtc %u : v p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n", - pipe, hpos, vpos, - (long)tv_etime.tv_sec, (long)tv_etime.tv_usec, - (long)vblank_time->tv_sec, (long)vblank_time->tv_usec, - duration_ns/1000, i); - - return true; -} -EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos); - -static struct timeval get_drm_timestamp(void) -{ - ktime_t now; - - now = drm_timestamp_monotonic ? ktime_get() : ktime_get_real(); - return ktime_to_timeval(now); -} - -/** - * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent - * vblank interval - * @dev: DRM device - * @pipe: index of CRTC whose vblank timestamp to retrieve - * @tvblank: Pointer to target struct timeval which should receive the timestamp - * @in_vblank_irq: - * True when called from drm_crtc_handle_vblank(). Some drivers - * need to apply some workarounds for gpu-specific vblank irq quirks - * if flag is set. - * - * Fetches the system timestamp corresponding to the time of the most recent - * vblank interval on specified CRTC. May call into kms-driver to - * compute the timestamp with a high-precision GPU specific method. - * - * Returns zero if timestamp originates from uncorrected do_gettimeofday() - * call, i.e., it isn't very precisely locked to the true vblank. - * - * Returns: - * True if timestamp is considered to be very precise, false otherwise. - */ -static bool -drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, - struct timeval *tvblank, bool in_vblank_irq) -{ - bool ret = false; - - /* Define requested maximum error on timestamps (nanoseconds). */ - int max_error = (int) drm_timestamp_precision * 1000; - - /* Query driver if possible and precision timestamping enabled. */ - if (dev->driver->get_vblank_timestamp && (max_error > 0)) - ret = dev->driver->get_vblank_timestamp(dev, pipe, &max_error, - tvblank, in_vblank_irq); - - /* GPU high precision timestamp query unsupported or failed. - * Return current monotonic/gettimeofday timestamp as best estimate. - */ - if (!ret) - *tvblank = get_drm_timestamp(); - - return ret; -} - -/** - * drm_crtc_vblank_count - retrieve "cooked" vblank counter value - * @crtc: which counter to retrieve - * - * Fetches the "cooked" vblank count value that represents the number of - * vblank events since the system was booted, including lost events due to - * modesetting activity. - * - * Returns: - * The software vblank counter. - */ -u32 drm_crtc_vblank_count(struct drm_crtc *crtc) -{ - return drm_vblank_count(crtc->dev, drm_crtc_index(crtc)); -} -EXPORT_SYMBOL(drm_crtc_vblank_count); - -/** - * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the - * system timestamp corresponding to that vblank counter value. - * @dev: DRM device - * @pipe: index of CRTC whose counter to retrieve - * @vblanktime: Pointer to struct timeval to receive the vblank timestamp. - * - * Fetches the "cooked" vblank count value that represents the number of - * vblank events since the system was booted, including lost events due to - * modesetting activity. Returns corresponding system timestamp of the time - * of the vblank interval that corresponds to the current vblank counter value. - * - * This is the legacy version of drm_crtc_vblank_count_and_time(). - */ -static u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe, - struct timeval *vblanktime) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - u32 vblank_count; - unsigned int seq; - - if (WARN_ON(pipe >= dev->num_crtcs)) { - *vblanktime = (struct timeval) { 0 }; - return 0; - } - - do { - seq = read_seqbegin(&vblank->seqlock); - vblank_count = vblank->count; - *vblanktime = vblank->time; - } while (read_seqretry(&vblank->seqlock, seq)); - - return vblank_count; -} - -/** - * drm_crtc_vblank_count_and_time - retrieve "cooked" vblank counter value - * and the system timestamp corresponding to that vblank counter value - * @crtc: which counter to retrieve - * @vblanktime: Pointer to struct timeval to receive the vblank timestamp. - * - * Fetches the "cooked" vblank count value that represents the number of - * vblank events since the system was booted, including lost events due to - * modesetting activity. Returns corresponding system timestamp of the time - * of the vblank interval that corresponds to the current vblank counter value. - */ -u32 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, - struct timeval *vblanktime) -{ - return drm_vblank_count_and_time(crtc->dev, drm_crtc_index(crtc), - vblanktime); -} -EXPORT_SYMBOL(drm_crtc_vblank_count_and_time); - -static void send_vblank_event(struct drm_device *dev, - struct drm_pending_vblank_event *e, - unsigned long seq, struct timeval *now) -{ - e->event.sequence = seq; - e->event.tv_sec = now->tv_sec; - e->event.tv_usec = now->tv_usec; - - trace_drm_vblank_event_delivered(e->base.file_priv, e->pipe, - e->event.sequence); - - drm_send_event_locked(dev, &e->base); -} - -/** - * drm_crtc_arm_vblank_event - arm vblank event after pageflip - * @crtc: the source CRTC of the vblank event - * @e: the event to send - * - * A lot of drivers need to generate vblank events for the very next vblank - * interrupt. For example when the page flip interrupt happens when the page - * flip gets armed, but not when it actually executes within the next vblank - * period. This helper function implements exactly the required vblank arming - * behaviour. - * - * NOTE: Drivers using this to send out the &drm_crtc_state.event as part of an - * atomic commit must ensure that the next vblank happens at exactly the same - * time as the atomic commit is committed to the hardware. This function itself - * does **not** protect again the next vblank interrupt racing with either this - * function call or the atomic commit operation. A possible sequence could be: - * - * 1. Driver commits new hardware state into vblank-synchronized registers. - * 2. A vblank happens, committing the hardware state. Also the corresponding - * vblank interrupt is fired off and fully processed by the interrupt - * handler. - * 3. The atomic commit operation proceeds to call drm_crtc_arm_vblank_event(). - * 4. The event is only send out for the next vblank, which is wrong. - * - * An equivalent race can happen when the driver calls - * drm_crtc_arm_vblank_event() before writing out the new hardware state. - * - * The only way to make this work safely is to prevent the vblank from firing - * (and the hardware from committing anything else) until the entire atomic - * commit sequence has run to completion. If the hardware does not have such a - * feature (e.g. using a "go" bit), then it is unsafe to use this functions. - * Instead drivers need to manually send out the event from their interrupt - * handler by calling drm_crtc_send_vblank_event() and make sure that there's no - * possible race with the hardware committing the atomic update. - * - * Caller must hold event lock. Caller must also hold a vblank reference for - * the event @e, which will be dropped when the next vblank arrives. - */ -void drm_crtc_arm_vblank_event(struct drm_crtc *crtc, - struct drm_pending_vblank_event *e) -{ - struct drm_device *dev = crtc->dev; - unsigned int pipe = drm_crtc_index(crtc); - - assert_spin_locked(&dev->event_lock); - - e->pipe = pipe; - e->event.sequence = drm_vblank_count(dev, pipe); - e->event.crtc_id = crtc->base.id; - list_add_tail(&e->base.link, &dev->vblank_event_list); -} -EXPORT_SYMBOL(drm_crtc_arm_vblank_event); - -/** - * drm_crtc_send_vblank_event - helper to send vblank event after pageflip - * @crtc: the source CRTC of the vblank event - * @e: the event to send - * - * Updates sequence # and timestamp on event for the most recently processed - * vblank, and sends it to userspace. Caller must hold event lock. - * - * See drm_crtc_arm_vblank_event() for a helper which can be used in certain - * situation, especially to send out events for atomic commit operations. - */ -void drm_crtc_send_vblank_event(struct drm_crtc *crtc, - struct drm_pending_vblank_event *e) -{ - struct drm_device *dev = crtc->dev; - unsigned int seq, pipe = drm_crtc_index(crtc); - struct timeval now; - - if (dev->num_crtcs > 0) { - seq = drm_vblank_count_and_time(dev, pipe, &now); - } else { - seq = 0; - - now = get_drm_timestamp(); - } - e->pipe = pipe; - e->event.crtc_id = crtc->base.id; - send_vblank_event(dev, e, seq, &now); -} -EXPORT_SYMBOL(drm_crtc_send_vblank_event); - -static int __enable_vblank(struct drm_device *dev, unsigned int pipe) -{ - if (drm_core_check_feature(dev, DRIVER_MODESET)) { - struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); - - if (crtc->funcs->enable_vblank) - return crtc->funcs->enable_vblank(crtc); - } - - return dev->driver->enable_vblank(dev, pipe); -} - -/** - * drm_vblank_enable - enable the vblank interrupt on a CRTC - * @dev: DRM device - * @pipe: CRTC index - * - * Returns: - * Zero on success or a negative error code on failure. - */ -static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - int ret = 0; - - assert_spin_locked(&dev->vbl_lock); - - spin_lock(&dev->vblank_time_lock); - - if (!vblank->enabled) { - /* - * Enable vblank irqs under vblank_time_lock protection. - * All vblank count & timestamp updates are held off - * until we are done reinitializing master counter and - * timestamps. Filtercode in drm_handle_vblank() will - * prevent double-accounting of same vblank interval. - */ - ret = __enable_vblank(dev, pipe); - DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe, ret); - if (ret) { - atomic_dec(&vblank->refcount); - } else { - drm_update_vblank_count(dev, pipe, 0); - /* drm_update_vblank_count() includes a wmb so we just - * need to ensure that the compiler emits the write - * to mark the vblank as enabled after the call - * to drm_update_vblank_count(). - */ - WRITE_ONCE(vblank->enabled, true); - } - } - - spin_unlock(&dev->vblank_time_lock); - - return ret; -} - -/** - * drm_vblank_get - get a reference count on vblank events - * @dev: DRM device - * @pipe: index of CRTC to own - * - * Acquire a reference count on vblank events to avoid having them disabled - * while in use. - * - * This is the legacy version of drm_crtc_vblank_get(). - * - * Returns: - * Zero on success or a negative error code on failure. - */ -static int drm_vblank_get(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - unsigned long irqflags; - int ret = 0; - - if (!dev->num_crtcs) - return -EINVAL; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return -EINVAL; - - spin_lock_irqsave(&dev->vbl_lock, irqflags); - /* Going from 0->1 means we have to enable interrupts again */ - if (atomic_add_return(1, &vblank->refcount) == 1) { - ret = drm_vblank_enable(dev, pipe); - } else { - if (!vblank->enabled) { - atomic_dec(&vblank->refcount); - ret = -EINVAL; - } - } - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); - - return ret; -} - -/** - * drm_crtc_vblank_get - get a reference count on vblank events - * @crtc: which CRTC to own - * - * Acquire a reference count on vblank events to avoid having them disabled - * while in use. - * - * Returns: - * Zero on success or a negative error code on failure. - */ -int drm_crtc_vblank_get(struct drm_crtc *crtc) -{ - return drm_vblank_get(crtc->dev, drm_crtc_index(crtc)); -} -EXPORT_SYMBOL(drm_crtc_vblank_get); - -/** - * drm_vblank_put - release ownership of vblank events - * @dev: DRM device - * @pipe: index of CRTC to release - * - * Release ownership of a given vblank counter, turning off interrupts - * if possible. Disable interrupts after drm_vblank_offdelay milliseconds. - * - * This is the legacy version of drm_crtc_vblank_put(). - */ -static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return; - - if (WARN_ON(atomic_read(&vblank->refcount) == 0)) - return; - - /* Last user schedules interrupt disable */ - if (atomic_dec_and_test(&vblank->refcount)) { - if (drm_vblank_offdelay == 0) - return; - else if (drm_vblank_offdelay < 0) - vblank_disable_fn((unsigned long)vblank); - else if (!dev->vblank_disable_immediate) - mod_timer(&vblank->disable_timer, - jiffies + ((drm_vblank_offdelay * HZ)/1000)); - } -} - -/** - * drm_crtc_vblank_put - give up ownership of vblank events - * @crtc: which counter to give up - * - * Release ownership of a given vblank counter, turning off interrupts - * if possible. Disable interrupts after drm_vblank_offdelay milliseconds. - */ -void drm_crtc_vblank_put(struct drm_crtc *crtc) -{ - drm_vblank_put(crtc->dev, drm_crtc_index(crtc)); -} -EXPORT_SYMBOL(drm_crtc_vblank_put); - -/** - * drm_wait_one_vblank - wait for one vblank - * @dev: DRM device - * @pipe: CRTC index - * - * This waits for one vblank to pass on @pipe, using the irq driver interfaces. - * It is a failure to call this when the vblank irq for @pipe is disabled, e.g. - * due to lack of driver support or because the crtc is off. - */ -void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - int ret; - u32 last; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return; - - ret = drm_vblank_get(dev, pipe); - if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", pipe, ret)) - return; - - last = drm_vblank_count(dev, pipe); - - ret = wait_event_timeout(vblank->queue, - last != drm_vblank_count(dev, pipe), - msecs_to_jiffies(100)); - - WARN(ret == 0, "vblank wait timed out on crtc %i\n", pipe); - - drm_vblank_put(dev, pipe); -} -EXPORT_SYMBOL(drm_wait_one_vblank); - -/** - * drm_crtc_wait_one_vblank - wait for one vblank - * @crtc: DRM crtc - * - * This waits for one vblank to pass on @crtc, using the irq driver interfaces. - * It is a failure to call this when the vblank irq for @crtc is disabled, e.g. - * due to lack of driver support or because the crtc is off. - */ -void drm_crtc_wait_one_vblank(struct drm_crtc *crtc) -{ - drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc)); -} -EXPORT_SYMBOL(drm_crtc_wait_one_vblank); - -/** - * drm_crtc_vblank_off - disable vblank events on a CRTC - * @crtc: CRTC in question - * - * Drivers can use this function to shut down the vblank interrupt handling when - * disabling a crtc. This function ensures that the latest vblank frame count is - * stored so that drm_vblank_on can restore it again. - * - * Drivers must use this function when the hardware vblank counter can get - * reset, e.g. when suspending. - */ -void drm_crtc_vblank_off(struct drm_crtc *crtc) -{ - struct drm_device *dev = crtc->dev; - unsigned int pipe = drm_crtc_index(crtc); - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - struct drm_pending_vblank_event *e, *t; - struct timeval now; - unsigned long irqflags; - unsigned int seq; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return; - - spin_lock_irqsave(&dev->event_lock, irqflags); - - spin_lock(&dev->vbl_lock); - DRM_DEBUG_VBL("crtc %d, vblank enabled %d, inmodeset %d\n", - pipe, vblank->enabled, vblank->inmodeset); - - /* Avoid redundant vblank disables without previous - * drm_crtc_vblank_on(). */ - if (drm_core_check_feature(dev, DRIVER_ATOMIC) || !vblank->inmodeset) - vblank_disable_and_save(dev, pipe); - - wake_up(&vblank->queue); - - /* - * Prevent subsequent drm_vblank_get() from re-enabling - * the vblank interrupt by bumping the refcount. - */ - if (!vblank->inmodeset) { - atomic_inc(&vblank->refcount); - vblank->inmodeset = 1; - } - spin_unlock(&dev->vbl_lock); - - /* Send any queued vblank events, lest the natives grow disquiet */ - seq = drm_vblank_count_and_time(dev, pipe, &now); - - list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) { - if (e->pipe != pipe) - continue; - DRM_DEBUG("Sending premature vblank event on disable: " - "wanted %u, current %u\n", - e->event.sequence, seq); - list_del(&e->base.link); - drm_vblank_put(dev, pipe); - send_vblank_event(dev, e, seq, &now); - } - spin_unlock_irqrestore(&dev->event_lock, irqflags); - - /* Will be reset by the modeset helpers when re-enabling the crtc by - * calling drm_calc_timestamping_constants(). */ - vblank->hwmode.crtc_clock = 0; -} -EXPORT_SYMBOL(drm_crtc_vblank_off); - -/** - * drm_crtc_vblank_reset - reset vblank state to off on a CRTC - * @crtc: CRTC in question - * - * Drivers can use this function to reset the vblank state to off at load time. - * Drivers should use this together with the drm_crtc_vblank_off() and - * drm_crtc_vblank_on() functions. The difference compared to - * drm_crtc_vblank_off() is that this function doesn't save the vblank counter - * and hence doesn't need to call any driver hooks. - */ -void drm_crtc_vblank_reset(struct drm_crtc *crtc) -{ - struct drm_device *dev = crtc->dev; - unsigned long irqflags; - unsigned int pipe = drm_crtc_index(crtc); - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - spin_lock_irqsave(&dev->vbl_lock, irqflags); - /* - * Prevent subsequent drm_vblank_get() from enabling the vblank - * interrupt by bumping the refcount. - */ - if (!vblank->inmodeset) { - atomic_inc(&vblank->refcount); - vblank->inmodeset = 1; - } - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); - - WARN_ON(!list_empty(&dev->vblank_event_list)); -} -EXPORT_SYMBOL(drm_crtc_vblank_reset); - -/** - * drm_crtc_vblank_on - enable vblank events on a CRTC - * @crtc: CRTC in question - * - * This functions restores the vblank interrupt state captured with - * drm_crtc_vblank_off() again. Note that calls to drm_crtc_vblank_on() and - * drm_crtc_vblank_off() can be unbalanced and so can also be unconditionally called - * in driver load code to reflect the current hardware state of the crtc. - */ -void drm_crtc_vblank_on(struct drm_crtc *crtc) -{ - struct drm_device *dev = crtc->dev; - unsigned int pipe = drm_crtc_index(crtc); - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - unsigned long irqflags; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return; - - spin_lock_irqsave(&dev->vbl_lock, irqflags); - DRM_DEBUG_VBL("crtc %d, vblank enabled %d, inmodeset %d\n", - pipe, vblank->enabled, vblank->inmodeset); - - /* Drop our private "prevent drm_vblank_get" refcount */ - if (vblank->inmodeset) { - atomic_dec(&vblank->refcount); - vblank->inmodeset = 0; - } - - drm_reset_vblank_timestamp(dev, pipe); - - /* - * re-enable interrupts if there are users left, or the - * user wishes vblank interrupts to be enabled all the time. - */ - if (atomic_read(&vblank->refcount) != 0 || drm_vblank_offdelay == 0) - WARN_ON(drm_vblank_enable(dev, pipe)); - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); -} -EXPORT_SYMBOL(drm_crtc_vblank_on); - -static void drm_legacy_vblank_pre_modeset(struct drm_device *dev, - unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - - /* vblank is not initialized (IRQ not installed ?), or has been freed */ - if (!dev->num_crtcs) - return; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return; - - /* - * To avoid all the problems that might happen if interrupts - * were enabled/disabled around or between these calls, we just - * have the kernel take a reference on the CRTC (just once though - * to avoid corrupting the count if multiple, mismatch calls occur), - * so that interrupts remain enabled in the interim. - */ - if (!vblank->inmodeset) { - vblank->inmodeset = 0x1; - if (drm_vblank_get(dev, pipe) == 0) - vblank->inmodeset |= 0x2; - } -} - -static void drm_legacy_vblank_post_modeset(struct drm_device *dev, - unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - unsigned long irqflags; - - /* vblank is not initialized (IRQ not installed ?), or has been freed */ - if (!dev->num_crtcs) - return; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return; - - if (vblank->inmodeset) { - spin_lock_irqsave(&dev->vbl_lock, irqflags); - drm_reset_vblank_timestamp(dev, pipe); - spin_unlock_irqrestore(&dev->vbl_lock, irqflags); - - if (vblank->inmodeset & 0x2) - drm_vblank_put(dev, pipe); - - vblank->inmodeset = 0; - } -} - -int drm_legacy_modeset_ctl(struct drm_device *dev, void *data, - struct drm_file *file_priv) -{ - struct drm_modeset_ctl *modeset = data; - unsigned int pipe; - - /* If drm_vblank_init() hasn't been called yet, just no-op */ - if (!dev->num_crtcs) - return 0; - - /* KMS drivers handle this internally */ - if (!drm_core_check_feature(dev, DRIVER_LEGACY)) - return 0; - - pipe = modeset->crtc; - if (pipe >= dev->num_crtcs) - return -EINVAL; - - switch (modeset->cmd) { - case _DRM_PRE_MODESET: - drm_legacy_vblank_pre_modeset(dev, pipe); - break; - case _DRM_POST_MODESET: - drm_legacy_vblank_post_modeset(dev, pipe); - break; - default: - return -EINVAL; - } - - return 0; -} - -static inline bool vblank_passed(u32 seq, u32 ref) -{ - return (seq - ref) <= (1 << 23); -} - -static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe, - union drm_wait_vblank *vblwait, - struct drm_file *file_priv) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - struct drm_pending_vblank_event *e; - struct timeval now; - unsigned long flags; - unsigned int seq; - int ret; - - e = kzalloc(sizeof(*e), GFP_KERNEL); - if (e == NULL) { - ret = -ENOMEM; - goto err_put; - } - - e->pipe = pipe; - e->event.base.type = DRM_EVENT_VBLANK; - e->event.base.length = sizeof(e->event); - e->event.user_data = vblwait->request.signal; - - spin_lock_irqsave(&dev->event_lock, flags); - - /* - * drm_crtc_vblank_off() might have been called after we called - * drm_vblank_get(). drm_crtc_vblank_off() holds event_lock around the - * vblank disable, so no need for further locking. The reference from - * drm_vblank_get() protects against vblank disable from another source. - */ - if (!READ_ONCE(vblank->enabled)) { - ret = -EINVAL; - goto err_unlock; - } - - ret = drm_event_reserve_init_locked(dev, file_priv, &e->base, - &e->event.base); - - if (ret) - goto err_unlock; - - seq = drm_vblank_count_and_time(dev, pipe, &now); - - DRM_DEBUG("event on vblank count %u, current %u, crtc %u\n", - vblwait->request.sequence, seq, pipe); - - trace_drm_vblank_event_queued(file_priv, pipe, - vblwait->request.sequence); - - e->event.sequence = vblwait->request.sequence; - if (vblank_passed(seq, vblwait->request.sequence)) { - drm_vblank_put(dev, pipe); - send_vblank_event(dev, e, seq, &now); - vblwait->reply.sequence = seq; - } else { - /* drm_handle_vblank_events will call drm_vblank_put */ - list_add_tail(&e->base.link, &dev->vblank_event_list); - vblwait->reply.sequence = vblwait->request.sequence; - } - - spin_unlock_irqrestore(&dev->event_lock, flags); - - return 0; - -err_unlock: - spin_unlock_irqrestore(&dev->event_lock, flags); - kfree(e); -err_put: - drm_vblank_put(dev, pipe); - return ret; -} - -static bool drm_wait_vblank_is_query(union drm_wait_vblank *vblwait) -{ - if (vblwait->request.sequence) - return false; - - return _DRM_VBLANK_RELATIVE == - (vblwait->request.type & (_DRM_VBLANK_TYPES_MASK | - _DRM_VBLANK_EVENT | - _DRM_VBLANK_NEXTONMISS)); -} - -/* - * Wait for VBLANK. - * - * \param inode device inode. - * \param file_priv DRM file private. - * \param cmd command. - * \param data user argument, pointing to a drm_wait_vblank structure. - * \return zero on success or a negative number on failure. - * - * This function enables the vblank interrupt on the pipe requested, then - * sleeps waiting for the requested sequence number to occur, and drops - * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that - * after a timeout with no further vblank waits scheduled). - */ -int drm_wait_vblank(struct drm_device *dev, void *data, - struct drm_file *file_priv) -{ - struct drm_vblank_crtc *vblank; - union drm_wait_vblank *vblwait = data; - int ret; - unsigned int flags, seq, pipe, high_pipe; - - if (!dev->irq_enabled) - return -EINVAL; - - if (vblwait->request.type & _DRM_VBLANK_SIGNAL) - return -EINVAL; - - if (vblwait->request.type & - ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK | - _DRM_VBLANK_HIGH_CRTC_MASK)) { - DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n", - vblwait->request.type, - (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK | - _DRM_VBLANK_HIGH_CRTC_MASK)); - return -EINVAL; - } - - flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK; - high_pipe = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK); - if (high_pipe) - pipe = high_pipe >> _DRM_VBLANK_HIGH_CRTC_SHIFT; - else - pipe = flags & _DRM_VBLANK_SECONDARY ? 1 : 0; - if (pipe >= dev->num_crtcs) - return -EINVAL; - - vblank = &dev->vblank[pipe]; - - /* If the counter is currently enabled and accurate, short-circuit - * queries to return the cached timestamp of the last vblank. - */ - if (dev->vblank_disable_immediate && - drm_wait_vblank_is_query(vblwait) && - READ_ONCE(vblank->enabled)) { - struct timeval now; - - vblwait->reply.sequence = - drm_vblank_count_and_time(dev, pipe, &now); - vblwait->reply.tval_sec = now.tv_sec; - vblwait->reply.tval_usec = now.tv_usec; - return 0; - } - - ret = drm_vblank_get(dev, pipe); - if (ret) { - DRM_DEBUG("crtc %d failed to acquire vblank counter, %d\n", pipe, ret); - return ret; - } - seq = drm_vblank_count(dev, pipe); - - switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) { - case _DRM_VBLANK_RELATIVE: - vblwait->request.sequence += seq; - vblwait->request.type &= ~_DRM_VBLANK_RELATIVE; - case _DRM_VBLANK_ABSOLUTE: - break; - default: - ret = -EINVAL; - goto done; - } - - if ((flags & _DRM_VBLANK_NEXTONMISS) && - vblank_passed(seq, vblwait->request.sequence)) - vblwait->request.sequence = seq + 1; - - if (flags & _DRM_VBLANK_EVENT) { - /* must hold on to the vblank ref until the event fires - * drm_vblank_put will be called asynchronously - */ - return drm_queue_vblank_event(dev, pipe, vblwait, file_priv); - } - - if (vblwait->request.sequence != seq) { - DRM_DEBUG("waiting on vblank count %u, crtc %u\n", - vblwait->request.sequence, pipe); - DRM_WAIT_ON(ret, vblank->queue, 3 * HZ, - vblank_passed(drm_vblank_count(dev, pipe), - vblwait->request.sequence) || - !READ_ONCE(vblank->enabled)); - } - - if (ret != -EINTR) { - struct timeval now; - - vblwait->reply.sequence = drm_vblank_count_and_time(dev, pipe, &now); - vblwait->reply.tval_sec = now.tv_sec; - vblwait->reply.tval_usec = now.tv_usec; - - DRM_DEBUG("crtc %d returning %u to client\n", - pipe, vblwait->reply.sequence); - } else { - DRM_DEBUG("crtc %d vblank wait interrupted by signal\n", pipe); - } - -done: - drm_vblank_put(dev, pipe); - return ret; -} - -static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe) -{ - struct drm_pending_vblank_event *e, *t; - struct timeval now; - unsigned int seq; - - assert_spin_locked(&dev->event_lock); - - seq = drm_vblank_count_and_time(dev, pipe, &now); - - list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) { - if (e->pipe != pipe) - continue; - if (!vblank_passed(seq, e->event.sequence)) - continue; - - DRM_DEBUG("vblank event on %u, current %u\n", - e->event.sequence, seq); - - list_del(&e->base.link); - drm_vblank_put(dev, pipe); - send_vblank_event(dev, e, seq, &now); - } - - trace_drm_vblank_event(pipe, seq); -} - -/** - * drm_handle_vblank - handle a vblank event - * @dev: DRM device - * @pipe: index of CRTC where this event occurred - * - * Drivers should call this routine in their vblank interrupt handlers to - * update the vblank counter and send any signals that may be pending. - * - * This is the legacy version of drm_crtc_handle_vblank(). - */ -bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe) -{ - struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; - unsigned long irqflags; - bool disable_irq; - - if (WARN_ON_ONCE(!dev->num_crtcs)) - return false; - - if (WARN_ON(pipe >= dev->num_crtcs)) - return false; - - spin_lock_irqsave(&dev->event_lock, irqflags); - - /* Need timestamp lock to prevent concurrent execution with - * vblank enable/disable, as this would cause inconsistent - * or corrupted timestamps and vblank counts. - */ - spin_lock(&dev->vblank_time_lock); - - /* Vblank irq handling disabled. Nothing to do. */ - if (!vblank->enabled) { - spin_unlock(&dev->vblank_time_lock); - spin_unlock_irqrestore(&dev->event_lock, irqflags); - return false; - } - - drm_update_vblank_count(dev, pipe, true); - - spin_unlock(&dev->vblank_time_lock); - - wake_up(&vblank->queue); - - /* With instant-off, we defer disabling the interrupt until after - * we finish processing the following vblank after all events have - * been signaled. The disable has to be last (after - * drm_handle_vblank_events) so that the timestamp is always accurate. - */ - disable_irq = (dev->vblank_disable_immediate && - drm_vblank_offdelay > 0 && - !atomic_read(&vblank->refcount)); - - drm_handle_vblank_events(dev, pipe); - - spin_unlock_irqrestore(&dev->event_lock, irqflags); - - if (disable_irq) - vblank_disable_fn((unsigned long)vblank); - - return true; -} -EXPORT_SYMBOL(drm_handle_vblank); - -/** - * drm_crtc_handle_vblank - handle a vblank event - * @crtc: where this event occurred - * - * Drivers should call this routine in their vblank interrupt handlers to - * update the vblank counter and send any signals that may be pending. - * - * This is the native KMS version of drm_handle_vblank(). - * - * Returns: - * True if the event was successfully handled, false on failure. - */ -bool drm_crtc_handle_vblank(struct drm_crtc *crtc) -{ - return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc)); -} -EXPORT_SYMBOL(drm_crtc_handle_vblank); diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c new file mode 100644 index 000000000000..630dc26379b7 --- /dev/null +++ b/drivers/gpu/drm/drm_vblank.c @@ -0,0 +1,1645 @@ +/* + * drm_irq.c IRQ and vblank support + * + * \author Rickard E. (Rik) Faith <faith@valinux.com> + * \author Gareth Hughes <gareth@valinux.com> + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +#include <drm/drm_vblank.h> +#include <drm/drmP.h> +#include <linux/export.h> + +#include "drm_trace.h" +#include "drm_internal.h" + +/* Retry timestamp calculation up to 3 times to satisfy + * drm_timestamp_precision before giving up. + */ +#define DRM_TIMESTAMP_MAXRETRIES 3 + +/* Threshold in nanoseconds for detection of redundant + * vblank irq in drm_handle_vblank(). 1 msec should be ok. + */ +#define DRM_REDUNDANT_VBLIRQ_THRESH_NS 1000000 + +static bool +drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, + struct timeval *tvblank, bool in_vblank_irq); + +static unsigned int drm_timestamp_precision = 20; /* Default to 20 usecs. */ + +/* + * Default to use monotonic timestamps for wait-for-vblank and page-flip + * complete events. + */ +unsigned int drm_timestamp_monotonic = 1; + +static int drm_vblank_offdelay = 5000; /* Default to 5000 msecs. */ + +module_param_named(vblankoffdelay, drm_vblank_offdelay, int, 0600); +module_param_named(timestamp_precision_usec, drm_timestamp_precision, int, 0600); +module_param_named(timestamp_monotonic, drm_timestamp_monotonic, int, 0600); +MODULE_PARM_DESC(vblankoffdelay, "Delay until vblank irq auto-disable [msecs] (0: never disable, <0: disable immediately)"); +MODULE_PARM_DESC(timestamp_precision_usec, "Max. error on timestamps [usecs]"); +MODULE_PARM_DESC(timestamp_monotonic, "Use monotonic timestamps"); + +static void store_vblank(struct drm_device *dev, unsigned int pipe, + u32 vblank_count_inc, + struct timeval *t_vblank, u32 last) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + + assert_spin_locked(&dev->vblank_time_lock); + + vblank->last = last; + + write_seqlock(&vblank->seqlock); + vblank->time = *t_vblank; + vblank->count += vblank_count_inc; + write_sequnlock(&vblank->seqlock); +} + +/* + * "No hw counter" fallback implementation of .get_vblank_counter() hook, + * if there is no useable hardware frame counter available. + */ +static u32 drm_vblank_no_hw_counter(struct drm_device *dev, unsigned int pipe) +{ + WARN_ON_ONCE(dev->max_vblank_count != 0); + return 0; +} + +static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe) +{ + if (drm_core_check_feature(dev, DRIVER_MODESET)) { + struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); + + if (crtc->funcs->get_vblank_counter) + return crtc->funcs->get_vblank_counter(crtc); + } + + if (dev->driver->get_vblank_counter) + return dev->driver->get_vblank_counter(dev, pipe); + + return drm_vblank_no_hw_counter(dev, pipe); +} + +/* + * Reset the stored timestamp for the current vblank count to correspond + * to the last vblank occurred. + * + * Only to be called from drm_crtc_vblank_on(). + * + * Note: caller must hold &drm_device.vbl_lock since this reads & writes + * device vblank fields. + */ +static void drm_reset_vblank_timestamp(struct drm_device *dev, unsigned int pipe) +{ + u32 cur_vblank; + bool rc; + struct timeval t_vblank; + int count = DRM_TIMESTAMP_MAXRETRIES; + + spin_lock(&dev->vblank_time_lock); + + /* + * sample the current counter to avoid random jumps + * when drm_vblank_enable() applies the diff + */ + do { + cur_vblank = __get_vblank_counter(dev, pipe); + rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, false); + } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); + + /* + * Only reinitialize corresponding vblank timestamp if high-precision query + * available and didn't fail. Otherwise reinitialize delayed at next vblank + * interrupt and assign 0 for now, to mark the vblanktimestamp as invalid. + */ + if (!rc) + t_vblank = (struct timeval) {0, 0}; + + /* + * +1 to make sure user will never see the same + * vblank counter value before and after a modeset + */ + store_vblank(dev, pipe, 1, &t_vblank, cur_vblank); + + spin_unlock(&dev->vblank_time_lock); +} + +/* + * Call back into the driver to update the appropriate vblank counter + * (specified by @pipe). Deal with wraparound, if it occurred, and + * update the last read value so we can deal with wraparound on the next + * call if necessary. + * + * Only necessary when going from off->on, to account for frames we + * didn't get an interrupt for. + * + * Note: caller must hold &drm_device.vbl_lock since this reads & writes + * device vblank fields. + */ +static void drm_update_vblank_count(struct drm_device *dev, unsigned int pipe, + bool in_vblank_irq) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + u32 cur_vblank, diff; + bool rc; + struct timeval t_vblank; + int count = DRM_TIMESTAMP_MAXRETRIES; + int framedur_ns = vblank->framedur_ns; + + /* + * Interrupts were disabled prior to this call, so deal with counter + * wrap if needed. + * NOTE! It's possible we lost a full dev->max_vblank_count + 1 events + * here if the register is small or we had vblank interrupts off for + * a long time. + * + * We repeat the hardware vblank counter & timestamp query until + * we get consistent results. This to prevent races between gpu + * updating its hardware counter while we are retrieving the + * corresponding vblank timestamp. + */ + do { + cur_vblank = __get_vblank_counter(dev, pipe); + rc = drm_get_last_vbltimestamp(dev, pipe, &t_vblank, in_vblank_irq); + } while (cur_vblank != __get_vblank_counter(dev, pipe) && --count > 0); + + if (dev->max_vblank_count != 0) { + /* trust the hw counter when it's around */ + diff = (cur_vblank - vblank->last) & dev->max_vblank_count; + } else if (rc && framedur_ns) { + const struct timeval *t_old; + u64 diff_ns; + + t_old = &vblank->time; + diff_ns = timeval_to_ns(&t_vblank) - timeval_to_ns(t_old); + + /* + * Figure out how many vblanks we've missed based + * on the difference in the timestamps and the + * frame/field duration. + */ + diff = DIV_ROUND_CLOSEST_ULL(diff_ns, framedur_ns); + + if (diff == 0 && in_vblank_irq) + DRM_DEBUG_VBL("crtc %u: Redundant vblirq ignored." + " diff_ns = %lld, framedur_ns = %d)\n", + pipe, (long long) diff_ns, framedur_ns); + } else { + /* some kind of default for drivers w/o accurate vbl timestamping */ + diff = in_vblank_irq ? 1 : 0; + } + + /* + * Within a drm_vblank_pre_modeset - drm_vblank_post_modeset + * interval? If so then vblank irqs keep running and it will likely + * happen that the hardware vblank counter is not trustworthy as it + * might reset at some point in that interval and vblank timestamps + * are not trustworthy either in that interval. Iow. this can result + * in a bogus diff >> 1 which must be avoided as it would cause + * random large forward jumps of the software vblank counter. + */ + if (diff > 1 && (vblank->inmodeset & 0x2)) { + DRM_DEBUG_VBL("clamping vblank bump to 1 on crtc %u: diffr=%u" + " due to pre-modeset.\n", pipe, diff); + diff = 1; + } + + DRM_DEBUG_VBL("updating vblank count on crtc %u:" + " current=%u, diff=%u, hw=%u hw_last=%u\n", + pipe, vblank->count, diff, cur_vblank, vblank->last); + + if (diff == 0) { + WARN_ON_ONCE(cur_vblank != vblank->last); + return; + } + + /* + * Only reinitialize corresponding vblank timestamp if high-precision query + * available and didn't fail, or we were called from the vblank interrupt. + * Otherwise reinitialize delayed at next vblank interrupt and assign 0 + * for now, to mark the vblanktimestamp as invalid. + */ + if (!rc && in_vblank_irq) + t_vblank = (struct timeval) {0, 0}; + + store_vblank(dev, pipe, diff, &t_vblank, cur_vblank); +} + +static u32 drm_vblank_count(struct drm_device *dev, unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return 0; + + return vblank->count; +} + +/** + * drm_accurate_vblank_count - retrieve the master vblank counter + * @crtc: which counter to retrieve + * + * This function is similar to @drm_crtc_vblank_count but this + * function interpolates to handle a race with vblank irq's. + * + * This is mostly useful for hardware that can obtain the scanout + * position, but doesn't have a frame counter. + */ +u32 drm_accurate_vblank_count(struct drm_crtc *crtc) +{ + struct drm_device *dev = crtc->dev; + unsigned int pipe = drm_crtc_index(crtc); + u32 vblank; + unsigned long flags; + + WARN(!dev->driver->get_vblank_timestamp, + "This function requires support for accurate vblank timestamps."); + + spin_lock_irqsave(&dev->vblank_time_lock, flags); + + drm_update_vblank_count(dev, pipe, false); + vblank = drm_vblank_count(dev, pipe); + + spin_unlock_irqrestore(&dev->vblank_time_lock, flags); + + return vblank; +} +EXPORT_SYMBOL(drm_accurate_vblank_count); + +static void __disable_vblank(struct drm_device *dev, unsigned int pipe) +{ + if (drm_core_check_feature(dev, DRIVER_MODESET)) { + struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); + + if (crtc->funcs->disable_vblank) { + crtc->funcs->disable_vblank(crtc); + return; + } + } + + dev->driver->disable_vblank(dev, pipe); +} + +/* + * Disable vblank irq's on crtc, make sure that last vblank count + * of hardware and corresponding consistent software vblank counter + * are preserved, even if there are any spurious vblank irq's after + * disable. + */ +void drm_vblank_disable_and_save(struct drm_device *dev, unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + unsigned long irqflags; + + assert_spin_locked(&dev->vbl_lock); + + /* Prevent vblank irq processing while disabling vblank irqs, + * so no updates of timestamps or count can happen after we've + * disabled. Needed to prevent races in case of delayed irq's. + */ + spin_lock_irqsave(&dev->vblank_time_lock, irqflags); + + /* + * Only disable vblank interrupts if they're enabled. This avoids + * calling the ->disable_vblank() operation in atomic context with the + * hardware potentially runtime suspended. + */ + if (vblank->enabled) { + __disable_vblank(dev, pipe); + vblank->enabled = false; + } + + /* + * Always update the count and timestamp to maintain the + * appearance that the counter has been ticking all along until + * this time. This makes the count account for the entire time + * between drm_crtc_vblank_on() and drm_crtc_vblank_off(). + */ + drm_update_vblank_count(dev, pipe, false); + + spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags); +} + +static void vblank_disable_fn(unsigned long arg) +{ + struct drm_vblank_crtc *vblank = (void *)arg; + struct drm_device *dev = vblank->dev; + unsigned int pipe = vblank->pipe; + unsigned long irqflags; + + spin_lock_irqsave(&dev->vbl_lock, irqflags); + if (atomic_read(&vblank->refcount) == 0 && vblank->enabled) { + DRM_DEBUG("disabling vblank on crtc %u\n", pipe); + drm_vblank_disable_and_save(dev, pipe); + } + spin_unlock_irqrestore(&dev->vbl_lock, irqflags); +} + +/** + * drm_vblank_cleanup - cleanup vblank support + * @dev: DRM device + * + * This function cleans up any resources allocated in drm_vblank_init. + */ +void drm_vblank_cleanup(struct drm_device *dev) +{ + unsigned int pipe; + + /* Bail if the driver didn't call drm_vblank_init() */ + if (dev->num_crtcs == 0) + return; + + for (pipe = 0; pipe < dev->num_crtcs; pipe++) { + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + + WARN_ON(READ_ONCE(vblank->enabled) && + drm_core_check_feature(dev, DRIVER_MODESET)); + + del_timer_sync(&vblank->disable_timer); + } + + kfree(dev->vblank); + + dev->num_crtcs = 0; +} +EXPORT_SYMBOL(drm_vblank_cleanup); + +/** + * drm_vblank_init - initialize vblank support + * @dev: DRM device + * @num_crtcs: number of CRTCs supported by @dev + * + * This function initializes vblank support for @num_crtcs display pipelines. + * + * Returns: + * Zero on success or a negative error code on failure. + */ +int drm_vblank_init(struct drm_device *dev, unsigned int num_crtcs) +{ + int ret = -ENOMEM; + unsigned int i; + + spin_lock_init(&dev->vbl_lock); + spin_lock_init(&dev->vblank_time_lock); + + dev->num_crtcs = num_crtcs; + + dev->vblank = kcalloc(num_crtcs, sizeof(*dev->vblank), GFP_KERNEL); + if (!dev->vblank) + goto err; + + for (i = 0; i < num_crtcs; i++) { + struct drm_vblank_crtc *vblank = &dev->vblank[i]; + + vblank->dev = dev; + vblank->pipe = i; + init_waitqueue_head(&vblank->queue); + setup_timer(&vblank->disable_timer, vblank_disable_fn, + (unsigned long)vblank); + seqlock_init(&vblank->seqlock); + } + + DRM_INFO("Supports vblank timestamp caching Rev 2 (21.10.2013).\n"); + + /* Driver specific high-precision vblank timestamping supported? */ + if (dev->driver->get_vblank_timestamp) + DRM_INFO("Driver supports precise vblank timestamp query.\n"); + else + DRM_INFO("No driver support for vblank timestamp query.\n"); + + /* Must have precise timestamping for reliable vblank instant disable */ + if (dev->vblank_disable_immediate && !dev->driver->get_vblank_timestamp) { + dev->vblank_disable_immediate = false; + DRM_INFO("Setting vblank_disable_immediate to false because " + "get_vblank_timestamp == NULL\n"); + } + + return 0; + +err: + dev->num_crtcs = 0; + return ret; +} +EXPORT_SYMBOL(drm_vblank_init); + +/** + * drm_crtc_vblank_waitqueue - get vblank waitqueue for the CRTC + * @crtc: which CRTC's vblank waitqueue to retrieve + * + * This function returns a pointer to the vblank waitqueue for the CRTC. + * Drivers can use this to implement vblank waits using wait_event() and related + * functions. + */ +wait_queue_head_t *drm_crtc_vblank_waitqueue(struct drm_crtc *crtc) +{ + return &crtc->dev->vblank[drm_crtc_index(crtc)].queue; +} +EXPORT_SYMBOL(drm_crtc_vblank_waitqueue); + + +/** + * drm_calc_timestamping_constants - calculate vblank timestamp constants + * @crtc: drm_crtc whose timestamp constants should be updated. + * @mode: display mode containing the scanout timings + * + * Calculate and store various constants which are later + * needed by vblank and swap-completion timestamping, e.g, + * by drm_calc_vbltimestamp_from_scanoutpos(). They are + * derived from CRTC's true scanout timing, so they take + * things like panel scaling or other adjustments into account. + */ +void drm_calc_timestamping_constants(struct drm_crtc *crtc, + const struct drm_display_mode *mode) +{ + struct drm_device *dev = crtc->dev; + unsigned int pipe = drm_crtc_index(crtc); + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + int linedur_ns = 0, framedur_ns = 0; + int dotclock = mode->crtc_clock; + + if (!dev->num_crtcs) + return; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return; + + /* Valid dotclock? */ + if (dotclock > 0) { + int frame_size = mode->crtc_htotal * mode->crtc_vtotal; + + /* + * Convert scanline length in pixels and video + * dot clock to line duration and frame duration + * in nanoseconds: + */ + linedur_ns = div_u64((u64) mode->crtc_htotal * 1000000, dotclock); + framedur_ns = div_u64((u64) frame_size * 1000000, dotclock); + + /* + * Fields of interlaced scanout modes are only half a frame duration. + */ + if (mode->flags & DRM_MODE_FLAG_INTERLACE) + framedur_ns /= 2; + } else + DRM_ERROR("crtc %u: Can't calculate constants, dotclock = 0!\n", + crtc->base.id); + + vblank->linedur_ns = linedur_ns; + vblank->framedur_ns = framedur_ns; + vblank->hwmode = *mode; + + DRM_DEBUG("crtc %u: hwmode: htotal %d, vtotal %d, vdisplay %d\n", + crtc->base.id, mode->crtc_htotal, + mode->crtc_vtotal, mode->crtc_vdisplay); + DRM_DEBUG("crtc %u: clock %d kHz framedur %d linedur %d\n", + crtc->base.id, dotclock, framedur_ns, linedur_ns); +} +EXPORT_SYMBOL(drm_calc_timestamping_constants); + +/** + * drm_calc_vbltimestamp_from_scanoutpos - precise vblank timestamp helper + * @dev: DRM device + * @pipe: index of CRTC whose vblank timestamp to retrieve + * @max_error: Desired maximum allowable error in timestamps (nanosecs) + * On return contains true maximum error of timestamp + * @vblank_time: Pointer to struct timeval which should receive the timestamp + * @in_vblank_irq: + * True when called from drm_crtc_handle_vblank(). Some drivers + * need to apply some workarounds for gpu-specific vblank irq quirks + * if flag is set. + * + * Implements calculation of exact vblank timestamps from given drm_display_mode + * timings and current video scanout position of a CRTC. This can be called from + * within get_vblank_timestamp() implementation of a kms driver to implement the + * actual timestamping. + * + * Should return timestamps conforming to the OML_sync_control OpenML + * extension specification. The timestamp corresponds to the end of + * the vblank interval, aka start of scanout of topmost-leftmost display + * pixel in the following video frame. + * + * Requires support for optional dev->driver->get_scanout_position() + * in kms driver, plus a bit of setup code to provide a drm_display_mode + * that corresponds to the true scanout timing. + * + * The current implementation only handles standard video modes. It + * returns as no operation if a doublescan or interlaced video mode is + * active. Higher level code is expected to handle this. + * + * This function can be used to implement the &drm_driver.get_vblank_timestamp + * directly, if the driver implements the &drm_driver.get_scanout_position hook. + * + * Note that atomic drivers must call drm_calc_timestamping_constants() before + * enabling a CRTC. The atomic helpers already take care of that in + * drm_atomic_helper_update_legacy_modeset_state(). + * + * Returns: + * + * Returns true on success, and false on failure, i.e. when no accurate + * timestamp could be acquired. + */ +bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev, + unsigned int pipe, + int *max_error, + struct timeval *vblank_time, + bool in_vblank_irq) +{ + struct timeval tv_etime; + ktime_t stime, etime; + bool vbl_status; + struct drm_crtc *crtc; + const struct drm_display_mode *mode; + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + int vpos, hpos, i; + int delta_ns, duration_ns; + + if (!drm_core_check_feature(dev, DRIVER_MODESET)) + return false; + + crtc = drm_crtc_from_index(dev, pipe); + + if (pipe >= dev->num_crtcs || !crtc) { + DRM_ERROR("Invalid crtc %u\n", pipe); + return false; + } + + /* Scanout position query not supported? Should not happen. */ + if (!dev->driver->get_scanout_position) { + DRM_ERROR("Called from driver w/o get_scanout_position()!?\n"); + return false; + } + + if (drm_drv_uses_atomic_modeset(dev)) + mode = &vblank->hwmode; + else + mode = &crtc->hwmode; + + /* If mode timing undefined, just return as no-op: + * Happens during initial modesetting of a crtc. + */ + if (mode->crtc_clock == 0) { + DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe); + WARN_ON_ONCE(drm_drv_uses_atomic_modeset(dev)); + + return false; + } + + /* Get current scanout position with system timestamp. + * Repeat query up to DRM_TIMESTAMP_MAXRETRIES times + * if single query takes longer than max_error nanoseconds. + * + * This guarantees a tight bound on maximum error if + * code gets preempted or delayed for some reason. + */ + for (i = 0; i < DRM_TIMESTAMP_MAXRETRIES; i++) { + /* + * Get vertical and horizontal scanout position vpos, hpos, + * and bounding timestamps stime, etime, pre/post query. + */ + vbl_status = dev->driver->get_scanout_position(dev, pipe, + in_vblank_irq, + &vpos, &hpos, + &stime, &etime, + mode); + + /* Return as no-op if scanout query unsupported or failed. */ + if (!vbl_status) { + DRM_DEBUG("crtc %u : scanoutpos query failed.\n", + pipe); + return false; + } + + /* Compute uncertainty in timestamp of scanout position query. */ + duration_ns = ktime_to_ns(etime) - ktime_to_ns(stime); + + /* Accept result with < max_error nsecs timing uncertainty. */ + if (duration_ns <= *max_error) + break; + } + + /* Noisy system timing? */ + if (i == DRM_TIMESTAMP_MAXRETRIES) { + DRM_DEBUG("crtc %u: Noisy timestamp %d us > %d us [%d reps].\n", + pipe, duration_ns/1000, *max_error/1000, i); + } + + /* Return upper bound of timestamp precision error. */ + *max_error = duration_ns; + + /* Convert scanout position into elapsed time at raw_time query + * since start of scanout at first display scanline. delta_ns + * can be negative if start of scanout hasn't happened yet. + */ + delta_ns = div_s64(1000000LL * (vpos * mode->crtc_htotal + hpos), + mode->crtc_clock); + + if (!drm_timestamp_monotonic) + etime = ktime_mono_to_real(etime); + + /* save this only for debugging purposes */ + tv_etime = ktime_to_timeval(etime); + /* Subtract time delta from raw timestamp to get final + * vblank_time timestamp for end of vblank. + */ + etime = ktime_sub_ns(etime, delta_ns); + *vblank_time = ktime_to_timeval(etime); + + DRM_DEBUG_VBL("crtc %u : v p(%d,%d)@ %ld.%ld -> %ld.%ld [e %d us, %d rep]\n", + pipe, hpos, vpos, + (long)tv_etime.tv_sec, (long)tv_etime.tv_usec, + (long)vblank_time->tv_sec, (long)vblank_time->tv_usec, + duration_ns/1000, i); + + return true; +} +EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos); + +static struct timeval get_drm_timestamp(void) +{ + ktime_t now; + + now = drm_timestamp_monotonic ? ktime_get() : ktime_get_real(); + return ktime_to_timeval(now); +} + +/** + * drm_get_last_vbltimestamp - retrieve raw timestamp for the most recent + * vblank interval + * @dev: DRM device + * @pipe: index of CRTC whose vblank timestamp to retrieve + * @tvblank: Pointer to target struct timeval which should receive the timestamp + * @in_vblank_irq: + * True when called from drm_crtc_handle_vblank(). Some drivers + * need to apply some workarounds for gpu-specific vblank irq quirks + * if flag is set. + * + * Fetches the system timestamp corresponding to the time of the most recent + * vblank interval on specified CRTC. May call into kms-driver to + * compute the timestamp with a high-precision GPU specific method. + * + * Returns zero if timestamp originates from uncorrected do_gettimeofday() + * call, i.e., it isn't very precisely locked to the true vblank. + * + * Returns: + * True if timestamp is considered to be very precise, false otherwise. + */ +static bool +drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe, + struct timeval *tvblank, bool in_vblank_irq) +{ + bool ret = false; + + /* Define requested maximum error on timestamps (nanoseconds). */ + int max_error = (int) drm_timestamp_precision * 1000; + + /* Query driver if possible and precision timestamping enabled. */ + if (dev->driver->get_vblank_timestamp && (max_error > 0)) + ret = dev->driver->get_vblank_timestamp(dev, pipe, &max_error, + tvblank, in_vblank_irq); + + /* GPU high precision timestamp query unsupported or failed. + * Return current monotonic/gettimeofday timestamp as best estimate. + */ + if (!ret) + *tvblank = get_drm_timestamp(); + + return ret; +} + +/** + * drm_crtc_vblank_count - retrieve "cooked" vblank counter value + * @crtc: which counter to retrieve + * + * Fetches the "cooked" vblank count value that represents the number of + * vblank events since the system was booted, including lost events due to + * modesetting activity. + * + * Returns: + * The software vblank counter. + */ +u32 drm_crtc_vblank_count(struct drm_crtc *crtc) +{ + return drm_vblank_count(crtc->dev, drm_crtc_index(crtc)); +} +EXPORT_SYMBOL(drm_crtc_vblank_count); + +/** + * drm_vblank_count_and_time - retrieve "cooked" vblank counter value and the + * system timestamp corresponding to that vblank counter value. + * @dev: DRM device + * @pipe: index of CRTC whose counter to retrieve + * @vblanktime: Pointer to struct timeval to receive the vblank timestamp. + * + * Fetches the "cooked" vblank count value that represents the number of + * vblank events since the system was booted, including lost events due to + * modesetting activity. Returns corresponding system timestamp of the time + * of the vblank interval that corresponds to the current vblank counter value. + * + * This is the legacy version of drm_crtc_vblank_count_and_time(). + */ +static u32 drm_vblank_count_and_time(struct drm_device *dev, unsigned int pipe, + struct timeval *vblanktime) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + u32 vblank_count; + unsigned int seq; + + if (WARN_ON(pipe >= dev->num_crtcs)) { + *vblanktime = (struct timeval) { 0 }; + return 0; + } + + do { + seq = read_seqbegin(&vblank->seqlock); + vblank_count = vblank->count; + *vblanktime = vblank->time; + } while (read_seqretry(&vblank->seqlock, seq)); + + return vblank_count; +} + +/** + * drm_crtc_vblank_count_and_time - retrieve "cooked" vblank counter value + * and the system timestamp corresponding to that vblank counter value + * @crtc: which counter to retrieve + * @vblanktime: Pointer to struct timeval to receive the vblank timestamp. + * + * Fetches the "cooked" vblank count value that represents the number of + * vblank events since the system was booted, including lost events due to + * modesetting activity. Returns corresponding system timestamp of the time + * of the vblank interval that corresponds to the current vblank counter value. + */ +u32 drm_crtc_vblank_count_and_time(struct drm_crtc *crtc, + struct timeval *vblanktime) +{ + return drm_vblank_count_and_time(crtc->dev, drm_crtc_index(crtc), + vblanktime); +} +EXPORT_SYMBOL(drm_crtc_vblank_count_and_time); + +static void send_vblank_event(struct drm_device *dev, + struct drm_pending_vblank_event *e, + unsigned long seq, struct timeval *now) +{ + e->event.sequence = seq; + e->event.tv_sec = now->tv_sec; + e->event.tv_usec = now->tv_usec; + + trace_drm_vblank_event_delivered(e->base.file_priv, e->pipe, + e->event.sequence); + + drm_send_event_locked(dev, &e->base); +} + +/** + * drm_crtc_arm_vblank_event - arm vblank event after pageflip + * @crtc: the source CRTC of the vblank event + * @e: the event to send + * + * A lot of drivers need to generate vblank events for the very next vblank + * interrupt. For example when the page flip interrupt happens when the page + * flip gets armed, but not when it actually executes within the next vblank + * period. This helper function implements exactly the required vblank arming + * behaviour. + * + * NOTE: Drivers using this to send out the &drm_crtc_state.event as part of an + * atomic commit must ensure that the next vblank happens at exactly the same + * time as the atomic commit is committed to the hardware. This function itself + * does **not** protect again the next vblank interrupt racing with either this + * function call or the atomic commit operation. A possible sequence could be: + * + * 1. Driver commits new hardware state into vblank-synchronized registers. + * 2. A vblank happens, committing the hardware state. Also the corresponding + * vblank interrupt is fired off and fully processed by the interrupt + * handler. + * 3. The atomic commit operation proceeds to call drm_crtc_arm_vblank_event(). + * 4. The event is only send out for the next vblank, which is wrong. + * + * An equivalent race can happen when the driver calls + * drm_crtc_arm_vblank_event() before writing out the new hardware state. + * + * The only way to make this work safely is to prevent the vblank from firing + * (and the hardware from committing anything else) until the entire atomic + * commit sequence has run to completion. If the hardware does not have such a + * feature (e.g. using a "go" bit), then it is unsafe to use this functions. + * Instead drivers need to manually send out the event from their interrupt + * handler by calling drm_crtc_send_vblank_event() and make sure that there's no + * possible race with the hardware committing the atomic update. + * + * Caller must hold event lock. Caller must also hold a vblank reference for + * the event @e, which will be dropped when the next vblank arrives. + */ +void drm_crtc_arm_vblank_event(struct drm_crtc *crtc, + struct drm_pending_vblank_event *e) +{ + struct drm_device *dev = crtc->dev; + unsigned int pipe = drm_crtc_index(crtc); + + assert_spin_locked(&dev->event_lock); + + e->pipe = pipe; + e->event.sequence = drm_vblank_count(dev, pipe); + e->event.crtc_id = crtc->base.id; + list_add_tail(&e->base.link, &dev->vblank_event_list); +} +EXPORT_SYMBOL(drm_crtc_arm_vblank_event); + +/** + * drm_crtc_send_vblank_event - helper to send vblank event after pageflip + * @crtc: the source CRTC of the vblank event + * @e: the event to send + * + * Updates sequence # and timestamp on event for the most recently processed + * vblank, and sends it to userspace. Caller must hold event lock. + * + * See drm_crtc_arm_vblank_event() for a helper which can be used in certain + * situation, especially to send out events for atomic commit operations. + */ +void drm_crtc_send_vblank_event(struct drm_crtc *crtc, + struct drm_pending_vblank_event *e) +{ + struct drm_device *dev = crtc->dev; + unsigned int seq, pipe = drm_crtc_index(crtc); + struct timeval now; + + if (dev->num_crtcs > 0) { + seq = drm_vblank_count_and_time(dev, pipe, &now); + } else { + seq = 0; + + now = get_drm_timestamp(); + } + e->pipe = pipe; + e->event.crtc_id = crtc->base.id; + send_vblank_event(dev, e, seq, &now); +} +EXPORT_SYMBOL(drm_crtc_send_vblank_event); + +static int __enable_vblank(struct drm_device *dev, unsigned int pipe) +{ + if (drm_core_check_feature(dev, DRIVER_MODESET)) { + struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); + + if (crtc->funcs->enable_vblank) + return crtc->funcs->enable_vblank(crtc); + } + + return dev->driver->enable_vblank(dev, pipe); +} + +/** + * drm_vblank_enable - enable the vblank interrupt on a CRTC + * @dev: DRM device + * @pipe: CRTC index + * + * Returns: + * Zero on success or a negative error code on failure. + */ +static int drm_vblank_enable(struct drm_device *dev, unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + int ret = 0; + + assert_spin_locked(&dev->vbl_lock); + + spin_lock(&dev->vblank_time_lock); + + if (!vblank->enabled) { + /* + * Enable vblank irqs under vblank_time_lock protection. + * All vblank count & timestamp updates are held off + * until we are done reinitializing master counter and + * timestamps. Filtercode in drm_handle_vblank() will + * prevent double-accounting of same vblank interval. + */ + ret = __enable_vblank(dev, pipe); + DRM_DEBUG("enabling vblank on crtc %u, ret: %d\n", pipe, ret); + if (ret) { + atomic_dec(&vblank->refcount); + } else { + drm_update_vblank_count(dev, pipe, 0); + /* drm_update_vblank_count() includes a wmb so we just + * need to ensure that the compiler emits the write + * to mark the vblank as enabled after the call + * to drm_update_vblank_count(). + */ + WRITE_ONCE(vblank->enabled, true); + } + } + + spin_unlock(&dev->vblank_time_lock); + + return ret; +} + +/** + * drm_vblank_get - get a reference count on vblank events + * @dev: DRM device + * @pipe: index of CRTC to own + * + * Acquire a reference count on vblank events to avoid having them disabled + * while in use. + * + * This is the legacy version of drm_crtc_vblank_get(). + * + * Returns: + * Zero on success or a negative error code on failure. + */ +static int drm_vblank_get(struct drm_device *dev, unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + unsigned long irqflags; + int ret = 0; + + if (!dev->num_crtcs) + return -EINVAL; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return -EINVAL; + + spin_lock_irqsave(&dev->vbl_lock, irqflags); + /* Going from 0->1 means we have to enable interrupts again */ + if (atomic_add_return(1, &vblank->refcount) == 1) { + ret = drm_vblank_enable(dev, pipe); + } else { + if (!vblank->enabled) { + atomic_dec(&vblank->refcount); + ret = -EINVAL; + } + } + spin_unlock_irqrestore(&dev->vbl_lock, irqflags); + + return ret; +} + +/** + * drm_crtc_vblank_get - get a reference count on vblank events + * @crtc: which CRTC to own + * + * Acquire a reference count on vblank events to avoid having them disabled + * while in use. + * + * Returns: + * Zero on success or a negative error code on failure. + */ +int drm_crtc_vblank_get(struct drm_crtc *crtc) +{ + return drm_vblank_get(crtc->dev, drm_crtc_index(crtc)); +} +EXPORT_SYMBOL(drm_crtc_vblank_get); + +/** + * drm_vblank_put - release ownership of vblank events + * @dev: DRM device + * @pipe: index of CRTC to release + * + * Release ownership of a given vblank counter, turning off interrupts + * if possible. Disable interrupts after drm_vblank_offdelay milliseconds. + * + * This is the legacy version of drm_crtc_vblank_put(). + */ +static void drm_vblank_put(struct drm_device *dev, unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return; + + if (WARN_ON(atomic_read(&vblank->refcount) == 0)) + return; + + /* Last user schedules interrupt disable */ + if (atomic_dec_and_test(&vblank->refcount)) { + if (drm_vblank_offdelay == 0) + return; + else if (drm_vblank_offdelay < 0) + vblank_disable_fn((unsigned long)vblank); + else if (!dev->vblank_disable_immediate) + mod_timer(&vblank->disable_timer, + jiffies + ((drm_vblank_offdelay * HZ)/1000)); + } +} + +/** + * drm_crtc_vblank_put - give up ownership of vblank events + * @crtc: which counter to give up + * + * Release ownership of a given vblank counter, turning off interrupts + * if possible. Disable interrupts after drm_vblank_offdelay milliseconds. + */ +void drm_crtc_vblank_put(struct drm_crtc *crtc) +{ + drm_vblank_put(crtc->dev, drm_crtc_index(crtc)); +} +EXPORT_SYMBOL(drm_crtc_vblank_put); + +/** + * drm_wait_one_vblank - wait for one vblank + * @dev: DRM device + * @pipe: CRTC index + * + * This waits for one vblank to pass on @pipe, using the irq driver interfaces. + * It is a failure to call this when the vblank irq for @pipe is disabled, e.g. + * due to lack of driver support or because the crtc is off. + */ +void drm_wait_one_vblank(struct drm_device *dev, unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + int ret; + u32 last; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return; + + ret = drm_vblank_get(dev, pipe); + if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", pipe, ret)) + return; + + last = drm_vblank_count(dev, pipe); + + ret = wait_event_timeout(vblank->queue, + last != drm_vblank_count(dev, pipe), + msecs_to_jiffies(100)); + + WARN(ret == 0, "vblank wait timed out on crtc %i\n", pipe); + + drm_vblank_put(dev, pipe); +} +EXPORT_SYMBOL(drm_wait_one_vblank); + +/** + * drm_crtc_wait_one_vblank - wait for one vblank + * @crtc: DRM crtc + * + * This waits for one vblank to pass on @crtc, using the irq driver interfaces. + * It is a failure to call this when the vblank irq for @crtc is disabled, e.g. + * due to lack of driver support or because the crtc is off. + */ +void drm_crtc_wait_one_vblank(struct drm_crtc *crtc) +{ + drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc)); +} +EXPORT_SYMBOL(drm_crtc_wait_one_vblank); + +/** + * drm_crtc_vblank_off - disable vblank events on a CRTC + * @crtc: CRTC in question + * + * Drivers can use this function to shut down the vblank interrupt handling when + * disabling a crtc. This function ensures that the latest vblank frame count is + * stored so that drm_vblank_on can restore it again. + * + * Drivers must use this function when the hardware vblank counter can get + * reset, e.g. when suspending. + */ +void drm_crtc_vblank_off(struct drm_crtc *crtc) +{ + struct drm_device *dev = crtc->dev; + unsigned int pipe = drm_crtc_index(crtc); + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + struct drm_pending_vblank_event *e, *t; + struct timeval now; + unsigned long irqflags; + unsigned int seq; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return; + + spin_lock_irqsave(&dev->event_lock, irqflags); + + spin_lock(&dev->vbl_lock); + DRM_DEBUG_VBL("crtc %d, vblank enabled %d, inmodeset %d\n", + pipe, vblank->enabled, vblank->inmodeset); + + /* Avoid redundant vblank disables without previous + * drm_crtc_vblank_on(). */ + if (drm_core_check_feature(dev, DRIVER_ATOMIC) || !vblank->inmodeset) + drm_vblank_disable_and_save(dev, pipe); + + wake_up(&vblank->queue); + + /* + * Prevent subsequent drm_vblank_get() from re-enabling + * the vblank interrupt by bumping the refcount. + */ + if (!vblank->inmodeset) { + atomic_inc(&vblank->refcount); + vblank->inmodeset = 1; + } + spin_unlock(&dev->vbl_lock); + + /* Send any queued vblank events, lest the natives grow disquiet */ + seq = drm_vblank_count_and_time(dev, pipe, &now); + + list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) { + if (e->pipe != pipe) + continue; + DRM_DEBUG("Sending premature vblank event on disable: " + "wanted %u, current %u\n", + e->event.sequence, seq); + list_del(&e->base.link); + drm_vblank_put(dev, pipe); + send_vblank_event(dev, e, seq, &now); + } + spin_unlock_irqrestore(&dev->event_lock, irqflags); + + /* Will be reset by the modeset helpers when re-enabling the crtc by + * calling drm_calc_timestamping_constants(). */ + vblank->hwmode.crtc_clock = 0; +} +EXPORT_SYMBOL(drm_crtc_vblank_off); + +/** + * drm_crtc_vblank_reset - reset vblank state to off on a CRTC + * @crtc: CRTC in question + * + * Drivers can use this function to reset the vblank state to off at load time. + * Drivers should use this together with the drm_crtc_vblank_off() and + * drm_crtc_vblank_on() functions. The difference compared to + * drm_crtc_vblank_off() is that this function doesn't save the vblank counter + * and hence doesn't need to call any driver hooks. + */ +void drm_crtc_vblank_reset(struct drm_crtc *crtc) +{ + struct drm_device *dev = crtc->dev; + unsigned long irqflags; + unsigned int pipe = drm_crtc_index(crtc); + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + + spin_lock_irqsave(&dev->vbl_lock, irqflags); + /* + * Prevent subsequent drm_vblank_get() from enabling the vblank + * interrupt by bumping the refcount. + */ + if (!vblank->inmodeset) { + atomic_inc(&vblank->refcount); + vblank->inmodeset = 1; + } + spin_unlock_irqrestore(&dev->vbl_lock, irqflags); + + WARN_ON(!list_empty(&dev->vblank_event_list)); +} +EXPORT_SYMBOL(drm_crtc_vblank_reset); + +/** + * drm_crtc_vblank_on - enable vblank events on a CRTC + * @crtc: CRTC in question + * + * This functions restores the vblank interrupt state captured with + * drm_crtc_vblank_off() again. Note that calls to drm_crtc_vblank_on() and + * drm_crtc_vblank_off() can be unbalanced and so can also be unconditionally called + * in driver load code to reflect the current hardware state of the crtc. + */ +void drm_crtc_vblank_on(struct drm_crtc *crtc) +{ + struct drm_device *dev = crtc->dev; + unsigned int pipe = drm_crtc_index(crtc); + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + unsigned long irqflags; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return; + + spin_lock_irqsave(&dev->vbl_lock, irqflags); + DRM_DEBUG_VBL("crtc %d, vblank enabled %d, inmodeset %d\n", + pipe, vblank->enabled, vblank->inmodeset); + + /* Drop our private "prevent drm_vblank_get" refcount */ + if (vblank->inmodeset) { + atomic_dec(&vblank->refcount); + vblank->inmodeset = 0; + } + + drm_reset_vblank_timestamp(dev, pipe); + + /* + * re-enable interrupts if there are users left, or the + * user wishes vblank interrupts to be enabled all the time. + */ + if (atomic_read(&vblank->refcount) != 0 || drm_vblank_offdelay == 0) + WARN_ON(drm_vblank_enable(dev, pipe)); + spin_unlock_irqrestore(&dev->vbl_lock, irqflags); +} +EXPORT_SYMBOL(drm_crtc_vblank_on); + +static void drm_legacy_vblank_pre_modeset(struct drm_device *dev, + unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + + /* vblank is not initialized (IRQ not installed ?), or has been freed */ + if (!dev->num_crtcs) + return; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return; + + /* + * To avoid all the problems that might happen if interrupts + * were enabled/disabled around or between these calls, we just + * have the kernel take a reference on the CRTC (just once though + * to avoid corrupting the count if multiple, mismatch calls occur), + * so that interrupts remain enabled in the interim. + */ + if (!vblank->inmodeset) { + vblank->inmodeset = 0x1; + if (drm_vblank_get(dev, pipe) == 0) + vblank->inmodeset |= 0x2; + } +} + +static void drm_legacy_vblank_post_modeset(struct drm_device *dev, + unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + unsigned long irqflags; + + /* vblank is not initialized (IRQ not installed ?), or has been freed */ + if (!dev->num_crtcs) + return; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return; + + if (vblank->inmodeset) { + spin_lock_irqsave(&dev->vbl_lock, irqflags); + drm_reset_vblank_timestamp(dev, pipe); + spin_unlock_irqrestore(&dev->vbl_lock, irqflags); + + if (vblank->inmodeset & 0x2) + drm_vblank_put(dev, pipe); + + vblank->inmodeset = 0; + } +} + +int drm_legacy_modeset_ctl(struct drm_device *dev, void *data, + struct drm_file *file_priv) +{ + struct drm_modeset_ctl *modeset = data; + unsigned int pipe; + + /* If drm_vblank_init() hasn't been called yet, just no-op */ + if (!dev->num_crtcs) + return 0; + + /* KMS drivers handle this internally */ + if (!drm_core_check_feature(dev, DRIVER_LEGACY)) + return 0; + + pipe = modeset->crtc; + if (pipe >= dev->num_crtcs) + return -EINVAL; + + switch (modeset->cmd) { + case _DRM_PRE_MODESET: + drm_legacy_vblank_pre_modeset(dev, pipe); + break; + case _DRM_POST_MODESET: + drm_legacy_vblank_post_modeset(dev, pipe); + break; + default: + return -EINVAL; + } + + return 0; +} + +static inline bool vblank_passed(u32 seq, u32 ref) +{ + return (seq - ref) <= (1 << 23); +} + +static int drm_queue_vblank_event(struct drm_device *dev, unsigned int pipe, + union drm_wait_vblank *vblwait, + struct drm_file *file_priv) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + struct drm_pending_vblank_event *e; + struct timeval now; + unsigned long flags; + unsigned int seq; + int ret; + + e = kzalloc(sizeof(*e), GFP_KERNEL); + if (e == NULL) { + ret = -ENOMEM; + goto err_put; + } + + e->pipe = pipe; + e->event.base.type = DRM_EVENT_VBLANK; + e->event.base.length = sizeof(e->event); + e->event.user_data = vblwait->request.signal; + + spin_lock_irqsave(&dev->event_lock, flags); + + /* + * drm_crtc_vblank_off() might have been called after we called + * drm_vblank_get(). drm_crtc_vblank_off() holds event_lock around the + * vblank disable, so no need for further locking. The reference from + * drm_vblank_get() protects against vblank disable from another source. + */ + if (!READ_ONCE(vblank->enabled)) { + ret = -EINVAL; + goto err_unlock; + } + + ret = drm_event_reserve_init_locked(dev, file_priv, &e->base, + &e->event.base); + + if (ret) + goto err_unlock; + + seq = drm_vblank_count_and_time(dev, pipe, &now); + + DRM_DEBUG("event on vblank count %u, current %u, crtc %u\n", + vblwait->request.sequence, seq, pipe); + + trace_drm_vblank_event_queued(file_priv, pipe, + vblwait->request.sequence); + + e->event.sequence = vblwait->request.sequence; + if (vblank_passed(seq, vblwait->request.sequence)) { + drm_vblank_put(dev, pipe); + send_vblank_event(dev, e, seq, &now); + vblwait->reply.sequence = seq; + } else { + /* drm_handle_vblank_events will call drm_vblank_put */ + list_add_tail(&e->base.link, &dev->vblank_event_list); + vblwait->reply.sequence = vblwait->request.sequence; + } + + spin_unlock_irqrestore(&dev->event_lock, flags); + + return 0; + +err_unlock: + spin_unlock_irqrestore(&dev->event_lock, flags); + kfree(e); +err_put: + drm_vblank_put(dev, pipe); + return ret; +} + +static bool drm_wait_vblank_is_query(union drm_wait_vblank *vblwait) +{ + if (vblwait->request.sequence) + return false; + + return _DRM_VBLANK_RELATIVE == + (vblwait->request.type & (_DRM_VBLANK_TYPES_MASK | + _DRM_VBLANK_EVENT | + _DRM_VBLANK_NEXTONMISS)); +} + +/* + * Wait for VBLANK. + * + * \param inode device inode. + * \param file_priv DRM file private. + * \param cmd command. + * \param data user argument, pointing to a drm_wait_vblank structure. + * \return zero on success or a negative number on failure. + * + * This function enables the vblank interrupt on the pipe requested, then + * sleeps waiting for the requested sequence number to occur, and drops + * the vblank interrupt refcount afterwards. (vblank IRQ disable follows that + * after a timeout with no further vblank waits scheduled). + */ +int drm_wait_vblank(struct drm_device *dev, void *data, + struct drm_file *file_priv) +{ + struct drm_vblank_crtc *vblank; + union drm_wait_vblank *vblwait = data; + int ret; + unsigned int flags, seq, pipe, high_pipe; + + if (!dev->irq_enabled) + return -EINVAL; + + if (vblwait->request.type & _DRM_VBLANK_SIGNAL) + return -EINVAL; + + if (vblwait->request.type & + ~(_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK | + _DRM_VBLANK_HIGH_CRTC_MASK)) { + DRM_ERROR("Unsupported type value 0x%x, supported mask 0x%x\n", + vblwait->request.type, + (_DRM_VBLANK_TYPES_MASK | _DRM_VBLANK_FLAGS_MASK | + _DRM_VBLANK_HIGH_CRTC_MASK)); + return -EINVAL; + } + + flags = vblwait->request.type & _DRM_VBLANK_FLAGS_MASK; + high_pipe = (vblwait->request.type & _DRM_VBLANK_HIGH_CRTC_MASK); + if (high_pipe) + pipe = high_pipe >> _DRM_VBLANK_HIGH_CRTC_SHIFT; + else + pipe = flags & _DRM_VBLANK_SECONDARY ? 1 : 0; + if (pipe >= dev->num_crtcs) + return -EINVAL; + + vblank = &dev->vblank[pipe]; + + /* If the counter is currently enabled and accurate, short-circuit + * queries to return the cached timestamp of the last vblank. + */ + if (dev->vblank_disable_immediate && + drm_wait_vblank_is_query(vblwait) && + READ_ONCE(vblank->enabled)) { + struct timeval now; + + vblwait->reply.sequence = + drm_vblank_count_and_time(dev, pipe, &now); + vblwait->reply.tval_sec = now.tv_sec; + vblwait->reply.tval_usec = now.tv_usec; + return 0; + } + + ret = drm_vblank_get(dev, pipe); + if (ret) { + DRM_DEBUG("crtc %d failed to acquire vblank counter, %d\n", pipe, ret); + return ret; + } + seq = drm_vblank_count(dev, pipe); + + switch (vblwait->request.type & _DRM_VBLANK_TYPES_MASK) { + case _DRM_VBLANK_RELATIVE: + vblwait->request.sequence += seq; + vblwait->request.type &= ~_DRM_VBLANK_RELATIVE; + case _DRM_VBLANK_ABSOLUTE: + break; + default: + ret = -EINVAL; + goto done; + } + + if ((flags & _DRM_VBLANK_NEXTONMISS) && + vblank_passed(seq, vblwait->request.sequence)) + vblwait->request.sequence = seq + 1; + + if (flags & _DRM_VBLANK_EVENT) { + /* must hold on to the vblank ref until the event fires + * drm_vblank_put will be called asynchronously + */ + return drm_queue_vblank_event(dev, pipe, vblwait, file_priv); + } + + if (vblwait->request.sequence != seq) { + DRM_DEBUG("waiting on vblank count %u, crtc %u\n", + vblwait->request.sequence, pipe); + DRM_WAIT_ON(ret, vblank->queue, 3 * HZ, + vblank_passed(drm_vblank_count(dev, pipe), + vblwait->request.sequence) || + !READ_ONCE(vblank->enabled)); + } + + if (ret != -EINTR) { + struct timeval now; + + vblwait->reply.sequence = drm_vblank_count_and_time(dev, pipe, &now); + vblwait->reply.tval_sec = now.tv_sec; + vblwait->reply.tval_usec = now.tv_usec; + + DRM_DEBUG("crtc %d returning %u to client\n", + pipe, vblwait->reply.sequence); + } else { + DRM_DEBUG("crtc %d vblank wait interrupted by signal\n", pipe); + } + +done: + drm_vblank_put(dev, pipe); + return ret; +} + +static void drm_handle_vblank_events(struct drm_device *dev, unsigned int pipe) +{ + struct drm_pending_vblank_event *e, *t; + struct timeval now; + unsigned int seq; + + assert_spin_locked(&dev->event_lock); + + seq = drm_vblank_count_and_time(dev, pipe, &now); + + list_for_each_entry_safe(e, t, &dev->vblank_event_list, base.link) { + if (e->pipe != pipe) + continue; + if (!vblank_passed(seq, e->event.sequence)) + continue; + + DRM_DEBUG("vblank event on %u, current %u\n", + e->event.sequence, seq); + + list_del(&e->base.link); + drm_vblank_put(dev, pipe); + send_vblank_event(dev, e, seq, &now); + } + + trace_drm_vblank_event(pipe, seq); +} + +/** + * drm_handle_vblank - handle a vblank event + * @dev: DRM device + * @pipe: index of CRTC where this event occurred + * + * Drivers should call this routine in their vblank interrupt handlers to + * update the vblank counter and send any signals that may be pending. + * + * This is the legacy version of drm_crtc_handle_vblank(). + */ +bool drm_handle_vblank(struct drm_device *dev, unsigned int pipe) +{ + struct drm_vblank_crtc *vblank = &dev->vblank[pipe]; + unsigned long irqflags; + bool disable_irq; + + if (WARN_ON_ONCE(!dev->num_crtcs)) + return false; + + if (WARN_ON(pipe >= dev->num_crtcs)) + return false; + + spin_lock_irqsave(&dev->event_lock, irqflags); + + /* Need timestamp lock to prevent concurrent execution with + * vblank enable/disable, as this would cause inconsistent + * or corrupted timestamps and vblank counts. + */ + spin_lock(&dev->vblank_time_lock); + + /* Vblank irq handling disabled. Nothing to do. */ + if (!vblank->enabled) { + spin_unlock(&dev->vblank_time_lock); + spin_unlock_irqrestore(&dev->event_lock, irqflags); + return false; + } + + drm_update_vblank_count(dev, pipe, true); + + spin_unlock(&dev->vblank_time_lock); + + wake_up(&vblank->queue); + + /* With instant-off, we defer disabling the interrupt until after + * we finish processing the following vblank after all events have + * been signaled. The disable has to be last (after + * drm_handle_vblank_events) so that the timestamp is always accurate. + */ + disable_irq = (dev->vblank_disable_immediate && + drm_vblank_offdelay > 0 && + !atomic_read(&vblank->refcount)); + + drm_handle_vblank_events(dev, pipe); + + spin_unlock_irqrestore(&dev->event_lock, irqflags); + + if (disable_irq) + vblank_disable_fn((unsigned long)vblank); + + return true; +} +EXPORT_SYMBOL(drm_handle_vblank); + +/** + * drm_crtc_handle_vblank - handle a vblank event + * @crtc: where this event occurred + * + * Drivers should call this routine in their vblank interrupt handlers to + * update the vblank counter and send any signals that may be pending. + * + * This is the native KMS version of drm_handle_vblank(). + * + * Returns: + * True if the event was successfully handled, false on failure. + */ +bool drm_crtc_handle_vblank(struct drm_crtc *crtc) +{ + return drm_handle_vblank(crtc->dev, drm_crtc_index(crtc)); +} +EXPORT_SYMBOL(drm_crtc_handle_vblank); |