drm: Add support for ARM's HDLCD controller.

The HDLCD controller is a display controller that supports resolutions
up to 4096x4096 pixels. It is present on various development boards
produced by ARM Ltd and emulated by the latest Fast Models from the
company.

Cc: David Airlie <airlied@linux.ie>
Cc: Robin Murphy <robin.murphy@arm.com>

Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>
[Kconfig cleanup and !CONFIG_PM fixes]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 550 insertions, 0 deletions

diff --git a/drivers/gpu/drm/arm/hdlcd_drv.c b/drivers/gpu/drm/arm/hdlcd_drv.c
new file mode 100644
index 000000000000..56b829f97699
--- /dev/null
+++ b/drivers/gpu/drm/arm/hdlcd_drv.c
@@ -0,0 +1,550 @@
+/*
+ * Copyright (C) 2013-2015 ARM Limited
+ * Author: Liviu Dudau <Liviu.Dudau@arm.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ *
+ *  ARM HDLCD Driver
+ */
+
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/list.h>
+#include <linux/of_graph.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/pm_runtime.h>
+
+#include <drm/drmP.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_of.h>
+
+#include "hdlcd_drv.h"
+#include "hdlcd_regs.h"
+
+static int hdlcd_load(struct drm_device *drm, unsigned long flags)
+{
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+	struct platform_device *pdev = to_platform_device(drm->dev);
+	struct resource *res;
+	u32 version;
+	int ret;
+
+	hdlcd->clk = devm_clk_get(drm->dev, "pxlclk");
+	if (IS_ERR(hdlcd->clk))
+		return PTR_ERR(hdlcd->clk);
+
+#ifdef CONFIG_DEBUG_FS
+	atomic_set(&hdlcd->buffer_underrun_count, 0);
+	atomic_set(&hdlcd->bus_error_count, 0);
+	atomic_set(&hdlcd->vsync_count, 0);
+	atomic_set(&hdlcd->dma_end_count, 0);
+#endif
+
+	INIT_LIST_HEAD(&hdlcd->event_list);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	hdlcd->mmio = devm_ioremap_resource(drm->dev, res);
+	if (IS_ERR(hdlcd->mmio)) {
+		DRM_ERROR("failed to map control registers area\n");
+		ret = PTR_ERR(hdlcd->mmio);
+		hdlcd->mmio = NULL;
+		goto fail;
+	}
+
+	version = hdlcd_read(hdlcd, HDLCD_REG_VERSION);
+	if ((version & HDLCD_PRODUCT_MASK) != HDLCD_PRODUCT_ID) {
+		DRM_ERROR("unknown product id: 0x%x\n", version);
+		ret = -EINVAL;
+		goto fail;
+	}
+	DRM_INFO("found ARM HDLCD version r%dp%d\n",
+		(version & HDLCD_VERSION_MAJOR_MASK) >> 8,
+		version & HDLCD_VERSION_MINOR_MASK);
+
+	/* Get the optional framebuffer memory resource */
+	ret = of_reserved_mem_device_init(drm->dev);
+	if (ret && ret != -ENODEV)
+		goto fail;
+
+	ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
+	if (ret)
+		goto setup_fail;
+
+	ret = hdlcd_setup_crtc(drm);
+	if (ret < 0) {
+		DRM_ERROR("failed to create crtc\n");
+		goto setup_fail;
+	}
+
+	pm_runtime_enable(drm->dev);
+
+	pm_runtime_get_sync(drm->dev);
+	ret = drm_irq_install(drm, platform_get_irq(pdev, 0));
+	pm_runtime_put_sync(drm->dev);
+	if (ret < 0) {
+		DRM_ERROR("failed to install IRQ handler\n");
+		goto irq_fail;
+	}
+
+	return 0;
+
+irq_fail:
+	drm_crtc_cleanup(&hdlcd->crtc);
+setup_fail:
+	of_reserved_mem_device_release(drm->dev);
+fail:
+	devm_clk_put(drm->dev, hdlcd->clk);
+
+	return ret;
+}
+
+static void hdlcd_fb_output_poll_changed(struct drm_device *drm)
+{
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+
+	if (hdlcd->fbdev)
+		drm_fbdev_cma_hotplug_event(hdlcd->fbdev);
+}
+
+static int hdlcd_atomic_commit(struct drm_device *dev,
+			       struct drm_atomic_state *state, bool async)
+{
+	return drm_atomic_helper_commit(dev, state, false);
+}
+
+static const struct drm_mode_config_funcs hdlcd_mode_config_funcs = {
+	.fb_create = drm_fb_cma_create,
+	.output_poll_changed = hdlcd_fb_output_poll_changed,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = hdlcd_atomic_commit,
+};
+
+static void hdlcd_setup_mode_config(struct drm_device *drm)
+{
+	drm_mode_config_init(drm);
+	drm->mode_config.min_width = 0;
+	drm->mode_config.min_height = 0;
+	drm->mode_config.max_width = HDLCD_MAX_XRES;
+	drm->mode_config.max_height = HDLCD_MAX_YRES;
+	drm->mode_config.funcs = &hdlcd_mode_config_funcs;
+}
+
+static void hdlcd_lastclose(struct drm_device *drm)
+{
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+
+	drm_fbdev_cma_restore_mode(hdlcd->fbdev);
+}
+
+static irqreturn_t hdlcd_irq(int irq, void *arg)
+{
+	struct drm_device *drm = arg;
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+	unsigned long irq_status;
+
+	irq_status = hdlcd_read(hdlcd, HDLCD_REG_INT_STATUS);
+
+#ifdef CONFIG_DEBUG_FS
+	if (irq_status & HDLCD_INTERRUPT_UNDERRUN)
+		atomic_inc(&hdlcd->buffer_underrun_count);
+
+	if (irq_status & HDLCD_INTERRUPT_DMA_END)
+		atomic_inc(&hdlcd->dma_end_count);
+
+	if (irq_status & HDLCD_INTERRUPT_BUS_ERROR)
+		atomic_inc(&hdlcd->bus_error_count);
+
+	if (irq_status & HDLCD_INTERRUPT_VSYNC)
+		atomic_inc(&hdlcd->vsync_count);
+
+#endif
+	if (irq_status & HDLCD_INTERRUPT_VSYNC) {
+		bool events_sent = false;
+		unsigned long flags;
+		struct drm_pending_vblank_event	*e, *t;
+
+		drm_crtc_handle_vblank(&hdlcd->crtc);
+
+		spin_lock_irqsave(&drm->event_lock, flags);
+		list_for_each_entry_safe(e, t, &hdlcd->event_list, base.link) {
+			list_del(&e->base.link);
+			drm_crtc_send_vblank_event(&hdlcd->crtc, e);
+			events_sent = true;
+		}
+		if (events_sent)
+			drm_crtc_vblank_put(&hdlcd->crtc);
+		spin_unlock_irqrestore(&drm->event_lock, flags);
+	}
+
+	/* acknowledge interrupt(s) */
+	hdlcd_write(hdlcd, HDLCD_REG_INT_CLEAR, irq_status);
+
+	return IRQ_HANDLED;
+}
+
+static void hdlcd_irq_preinstall(struct drm_device *drm)
+{
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+	/* Ensure interrupts are disabled */
+	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, 0);
+	hdlcd_write(hdlcd, HDLCD_REG_INT_CLEAR, ~0);
+}
+
+static int hdlcd_irq_postinstall(struct drm_device *drm)
+{
+#ifdef CONFIG_DEBUG_FS
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+	unsigned long irq_mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
+
+	/* enable debug interrupts */
+	irq_mask |= HDLCD_DEBUG_INT_MASK;
+
+	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, irq_mask);
+#endif
+	return 0;
+}
+
+static void hdlcd_irq_uninstall(struct drm_device *drm)
+{
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+	/* disable all the interrupts that we might have enabled */
+	unsigned long irq_mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
+
+#ifdef CONFIG_DEBUG_FS
+	/* disable debug interrupts */
+	irq_mask &= ~HDLCD_DEBUG_INT_MASK;
+#endif
+
+	/* disable vsync interrupts */
+	irq_mask &= ~HDLCD_INTERRUPT_VSYNC;
+
+	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, irq_mask);
+}
+
+static int hdlcd_enable_vblank(struct drm_device *drm, unsigned int crtc)
+{
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+	unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
+
+	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask | HDLCD_INTERRUPT_VSYNC);
+
+	return 0;
+}
+
+static void hdlcd_disable_vblank(struct drm_device *drm, unsigned int crtc)
+{
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+	unsigned int mask = hdlcd_read(hdlcd, HDLCD_REG_INT_MASK);
+
+	hdlcd_write(hdlcd, HDLCD_REG_INT_MASK, mask & ~HDLCD_INTERRUPT_VSYNC);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int hdlcd_show_underrun_count(struct seq_file *m, void *arg)
+{
+	struct drm_info_node *node = (struct drm_info_node *)m->private;
+	struct drm_device *drm = node->minor->dev;
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+
+	seq_printf(m, "underrun : %d\n", atomic_read(&hdlcd->buffer_underrun_count));
+	seq_printf(m, "dma_end  : %d\n", atomic_read(&hdlcd->dma_end_count));
+	seq_printf(m, "bus_error: %d\n", atomic_read(&hdlcd->bus_error_count));
+	seq_printf(m, "vsync    : %d\n", atomic_read(&hdlcd->vsync_count));
+	return 0;
+}
+
+static int hdlcd_show_pxlclock(struct seq_file *m, void *arg)
+{
+	struct drm_info_node *node = (struct drm_info_node *)m->private;
+	struct drm_device *drm = node->minor->dev;
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+	unsigned long clkrate = clk_get_rate(hdlcd->clk);
+	unsigned long mode_clock = hdlcd->crtc.mode.crtc_clock * 1000;
+
+	seq_printf(m, "hw  : %lu\n", clkrate);
+	seq_printf(m, "mode: %lu\n", mode_clock);
+	return 0;
+}
+
+static struct drm_info_list hdlcd_debugfs_list[] = {
+	{ "interrupt_count", hdlcd_show_underrun_count, 0 },
+	{ "clocks", hdlcd_show_pxlclock, 0 },
+};
+
+static int hdlcd_debugfs_init(struct drm_minor *minor)
+{
+	return drm_debugfs_create_files(hdlcd_debugfs_list,
+		ARRAY_SIZE(hdlcd_debugfs_list),	minor->debugfs_root, minor);
+}
+
+static void hdlcd_debugfs_cleanup(struct drm_minor *minor)
+{
+	drm_debugfs_remove_files(hdlcd_debugfs_list,
+		ARRAY_SIZE(hdlcd_debugfs_list), minor);
+}
+#endif
+
+static const struct file_operations fops = {
+	.owner		= THIS_MODULE,
+	.open		= drm_open,
+	.release	= drm_release,
+	.unlocked_ioctl	= drm_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= drm_compat_ioctl,
+#endif
+	.poll		= drm_poll,
+	.read		= drm_read,
+	.llseek		= noop_llseek,
+	.mmap		= drm_gem_cma_mmap,
+};
+
+static struct drm_driver hdlcd_driver = {
+	.driver_features = DRIVER_HAVE_IRQ | DRIVER_GEM |
+			   DRIVER_MODESET | DRIVER_PRIME |
+			   DRIVER_ATOMIC,
+	.lastclose = hdlcd_lastclose,
+	.irq_handler = hdlcd_irq,
+	.irq_preinstall = hdlcd_irq_preinstall,
+	.irq_postinstall = hdlcd_irq_postinstall,
+	.irq_uninstall = hdlcd_irq_uninstall,
+	.get_vblank_counter = drm_vblank_no_hw_counter,
+	.enable_vblank = hdlcd_enable_vblank,
+	.disable_vblank = hdlcd_disable_vblank,
+	.gem_free_object = drm_gem_cma_free_object,
+	.gem_vm_ops = &drm_gem_cma_vm_ops,
+	.dumb_create = drm_gem_cma_dumb_create,
+	.dumb_map_offset = drm_gem_cma_dumb_map_offset,
+	.dumb_destroy = drm_gem_dumb_destroy,
+	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
+	.gem_prime_export = drm_gem_prime_export,
+	.gem_prime_import = drm_gem_prime_import,
+	.gem_prime_get_sg_table = drm_gem_cma_prime_get_sg_table,
+	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+	.gem_prime_vmap = drm_gem_cma_prime_vmap,
+	.gem_prime_vunmap = drm_gem_cma_prime_vunmap,
+	.gem_prime_mmap = drm_gem_cma_prime_mmap,
+#ifdef CONFIG_DEBUG_FS
+	.debugfs_init = hdlcd_debugfs_init,
+	.debugfs_cleanup = hdlcd_debugfs_cleanup,
+#endif
+	.fops = &fops,
+	.name = "hdlcd",
+	.desc = "ARM HDLCD Controller DRM",
+	.date = "20151021",
+	.major = 1,
+	.minor = 0,
+};
+
+static int hdlcd_drm_bind(struct device *dev)
+{
+	struct drm_device *drm;
+	struct hdlcd_drm_private *hdlcd;
+	int ret;
+
+	hdlcd = devm_kzalloc(dev, sizeof(*hdlcd), GFP_KERNEL);
+	if (!hdlcd)
+		return -ENOMEM;
+
+	drm = drm_dev_alloc(&hdlcd_driver, dev);
+	if (!drm)
+		return -ENOMEM;
+
+	drm->dev_private = hdlcd;
+	hdlcd_setup_mode_config(drm);
+	ret = hdlcd_load(drm, 0);
+	if (ret)
+		goto err_free;
+
+	ret = drm_dev_register(drm, 0);
+	if (ret)
+		goto err_unload;
+
+	dev_set_drvdata(dev, drm);
+
+	ret = component_bind_all(dev, drm);
+	if (ret) {
+		DRM_ERROR("Failed to bind all components\n");
+		goto err_unregister;
+	}
+
+	ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
+	if (ret < 0) {
+		DRM_ERROR("failed to initialise vblank\n");
+		goto err_vblank;
+	}
+	drm->vblank_disable_allowed = true;
+
+	drm_mode_config_reset(drm);
+	drm_kms_helper_poll_init(drm);
+
+	hdlcd->fbdev = drm_fbdev_cma_init(drm, 32, drm->mode_config.num_crtc,
+					  drm->mode_config.num_connector);
+
+	if (IS_ERR(hdlcd->fbdev)) {
+		ret = PTR_ERR(hdlcd->fbdev);
+		hdlcd->fbdev = NULL;
+		goto err_fbdev;
+	}
+
+	return 0;
+
+err_fbdev:
+	drm_kms_helper_poll_fini(drm);
+	drm_mode_config_cleanup(drm);
+	drm_vblank_cleanup(drm);
+err_vblank:
+	component_unbind_all(dev, drm);
+err_unregister:
+	drm_dev_unregister(drm);
+err_unload:
+	pm_runtime_get_sync(drm->dev);
+	drm_irq_uninstall(drm);
+	pm_runtime_put_sync(drm->dev);
+	pm_runtime_disable(drm->dev);
+	of_reserved_mem_device_release(drm->dev);
+	devm_clk_put(dev, hdlcd->clk);
+err_free:
+	drm_dev_unref(drm);
+
+	return ret;
+}
+
+static void hdlcd_drm_unbind(struct device *dev)
+{
+	struct drm_device *drm = dev_get_drvdata(dev);
+	struct hdlcd_drm_private *hdlcd = drm->dev_private;
+
+	if (hdlcd->fbdev) {
+		drm_fbdev_cma_fini(hdlcd->fbdev);
+		hdlcd->fbdev = NULL;
+	}
+	drm_kms_helper_poll_fini(drm);
+	component_unbind_all(dev, drm);
+	drm_vblank_cleanup(drm);
+	pm_runtime_get_sync(drm->dev);
+	drm_irq_uninstall(drm);
+	pm_runtime_put_sync(drm->dev);
+	pm_runtime_disable(drm->dev);
+	of_reserved_mem_device_release(drm->dev);
+	if (!IS_ERR(hdlcd->clk)) {
+		devm_clk_put(drm->dev, hdlcd->clk);
+		hdlcd->clk = NULL;
+	}
+	drm_mode_config_cleanup(drm);
+	drm_dev_unregister(drm);
+	drm_dev_unref(drm);
+	drm->dev_private = NULL;
+	dev_set_drvdata(dev, NULL);
+}
+
+static const struct component_master_ops hdlcd_master_ops = {
+	.bind		= hdlcd_drm_bind,
+	.unbind		= hdlcd_drm_unbind,
+};
+
+static int compare_dev(struct device *dev, void *data)
+{
+	return dev->of_node == data;
+}
+
+static int hdlcd_probe(struct platform_device *pdev)
+{
+	struct device_node *port, *ep;
+	struct component_match *match = NULL;
+
+	if (!pdev->dev.of_node)
+		return -ENODEV;
+
+	/* there is only one output port inside each device, find it */
+	ep = of_graph_get_next_endpoint(pdev->dev.of_node, NULL);
+	if (!ep)
+		return -ENODEV;
+
+	if (!of_device_is_available(ep)) {
+		of_node_put(ep);
+		return -ENODEV;
+	}
+
+	/* add the remote encoder port as component */
+	port = of_graph_get_remote_port_parent(ep);
+	of_node_put(ep);
+	if (!port || !of_device_is_available(port)) {
+		of_node_put(port);
+		return -EAGAIN;
+	}
+
+	component_match_add(&pdev->dev, &match, compare_dev, port);
+
+	return component_master_add_with_match(&pdev->dev, &hdlcd_master_ops,
+					       match);
+}
+
+static int hdlcd_remove(struct platform_device *pdev)
+{
+	component_master_del(&pdev->dev, &hdlcd_master_ops);
+	return 0;
+}
+
+static const struct of_device_id  hdlcd_of_match[] = {
+	{ .compatible	= "arm,hdlcd" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, hdlcd_of_match);
+
+static int __maybe_unused hdlcd_pm_suspend(struct device *dev)
+{
+	struct drm_device *drm = dev_get_drvdata(dev);
+	struct drm_crtc *crtc;
+
+	if (pm_runtime_suspended(dev))
+		return 0;
+
+	drm_modeset_lock_all(drm);
+	list_for_each_entry(crtc, &drm->mode_config.crtc_list, head)
+		hdlcd_crtc_suspend(crtc);
+	drm_modeset_unlock_all(drm);
+	return 0;
+}
+
+static int __maybe_unused hdlcd_pm_resume(struct device *dev)
+{
+	struct drm_device *drm = dev_get_drvdata(dev);
+	struct drm_crtc *crtc;
+
+	if (!pm_runtime_suspended(dev))
+		return 0;
+
+	drm_modeset_lock_all(drm);
+	list_for_each_entry(crtc, &drm->mode_config.crtc_list, head)
+		hdlcd_crtc_resume(crtc);
+	drm_modeset_unlock_all(drm);
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(hdlcd_pm_ops, hdlcd_pm_suspend, hdlcd_pm_resume);
+
+static struct platform_driver hdlcd_platform_driver = {
+	.probe		= hdlcd_probe,
+	.remove		= hdlcd_remove,
+	.driver	= {
+		.name = "hdlcd",
+		.pm = &hdlcd_pm_ops,
+		.of_match_table	= hdlcd_of_match,
+	},
+};
+
+module_platform_driver(hdlcd_platform_driver);
+
+MODULE_AUTHOR("Liviu Dudau");
+MODULE_DESCRIPTION("ARM HDLCD DRM driver");
+MODULE_LICENSE("GPL v2");