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2016-03-25Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linuxLinus Torvalds1-1/+1
Pull drm fixes from Dave Airlie: "Just a couple of dma-buf related fixes and some amdgpu fixes, along with a regression fix for radeon off but default feature, but makes my 30" monitor happy again" * 'drm-next' of git://people.freedesktop.org/~airlied/linux: drm/radeon/mst: cleanup code indentation drm/radeon/mst: fix regression in lane/link handling. drm/amdgpu: add invalidate_page callback for userptrs drm/amdgpu: Revert "remove the userptr rmn->lock" drm/amdgpu: clean up path handling for powerplay drm/amd/powerplay: fix memory leak of tdp_table dma-buf/fence: fix fence_is_later v2 dma-buf: Update docs for SYNC ioctl drm: remove excess description dma-buf, drm, ion: Propagate error code from dma_buf_start_cpu_access() drm/atmel-hlcdc: use helper to get crtc state drm/atomic: use helper to get crtc state
2016-03-21dma-buf/fence: fix fence_is_later v2Christian König1-1/+1
A fence is never later than itself. This caused a bunch of overhead for AMDGPU. v2: simplify check as suggested by Michel. Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Michel Dänzer <michel.daenzer@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-02-07staging/android: remove struct sync_ptGustavo Padovan1-0/+2
struct sync_pt was just wrapping around struct fence and creating an extra abstraction layer. The only two members of struct sync_pt, child_list and active_list, were moved to struct fence in an earlier commit. After removing those two members struct sync_pt is nothing more than struct fence, so remove it all and use struct fence directly. Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-30dma-buf/fence: add fence_is_later()Christian König1-3/+19
Return true when fence 1 is later than fence 2 without checking if any of them are signaled. Useful for driver specific resource handling based on fences. Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
2015-10-30dma-buf/fence: add fence_wait_any_timeout function v2Christian König1-1/+2
Waiting for the first fence in an array of fences to signal. This is useful for device driver specific resource managers and also Vulkan needs something similar. v2: more parameter checks, handling for timeout==0, remove NULL entry support, better callback removal. Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
2014-11-03treewide: Fix typo in Documentation/DocBook/device-driversMasanari Iida1-2/+2
This patch fix speeling typo found in html files within Documentation/DocBook/device-drivers. It is because html files are generated from comments in source, so I have to fix comments in the source. Signed-off-by: Masanari Iida <standby24x7@gmail.com> Acked-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2014-07-08reservation: add suppport for read-only access using rcuMaarten Lankhorst1-0/+17
This adds some extra functions to deal with rcu. reservation_object_get_fences_rcu() will obtain the list of shared and exclusive fences without obtaining the ww_mutex. reservation_object_wait_timeout_rcu() will wait on all fences of the reservation_object, without obtaining the ww_mutex. reservation_object_test_signaled_rcu() will test if all fences of the reservation_object are signaled without using the ww_mutex. reservation_object_get_excl and reservation_object_get_list require the reservation object to be held, updating requires write_seqcount_begin/end. If only the exclusive fence is needed, rcu_dereference followed by fence_get_rcu can be used, if the shared fences are needed it's recommended to use the supplied functions. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Daniel Vetter <daniel@ffwll.ch> Reviewed-By: Thomas Hellstrom <thellstrom@vmware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-08fence: dma-buf cross-device synchronization (v18)Maarten Lankhorst1-0/+343
A fence can be attached to a buffer which is being filled or consumed by hw, to allow userspace to pass the buffer without waiting to another device. For example, userspace can call page_flip ioctl to display the next frame of graphics after kicking the GPU but while the GPU is still rendering. The display device sharing the buffer with the GPU would attach a callback to get notified when the GPU's rendering-complete IRQ fires, to update the scan-out address of the display, without having to wake up userspace. A driver must allocate a fence context for each execution ring that can run in parallel. The function for this takes an argument with how many contexts to allocate: + fence_context_alloc() A fence is transient, one-shot deal. It is allocated and attached to one or more dma-buf's. When the one that attached it is done, with the pending operation, it can signal the fence: + fence_signal() To have a rough approximation whether a fence is fired, call: + fence_is_signaled() The dma-buf-mgr handles tracking, and waiting on, the fences associated with a dma-buf. The one pending on the fence can add an async callback: + fence_add_callback() The callback can optionally be cancelled with: + fence_remove_callback() To wait synchronously, optionally with a timeout: + fence_wait() + fence_wait_timeout() When emitting a fence, call: + trace_fence_emit() To annotate that a fence is blocking on another fence, call: + trace_fence_annotate_wait_on(fence, on_fence) A default software-only implementation is provided, which can be used by drivers attaching a fence to a buffer when they have no other means for hw sync. But a memory backed fence is also envisioned, because it is common that GPU's can write to, or poll on some memory location for synchronization. For example: fence = custom_get_fence(...); if ((seqno_fence = to_seqno_fence(fence)) != NULL) { dma_buf *fence_buf = seqno_fence->sync_buf; get_dma_buf(fence_buf); ... tell the hw the memory location to wait ... custom_wait_on(fence_buf, seqno_fence->seqno_ofs, fence->seqno); } else { /* fall-back to sw sync * / fence_add_callback(fence, my_cb); } On SoC platforms, if some other hw mechanism is provided for synchronizing between IP blocks, it could be supported as an alternate implementation with it's own fence ops in a similar way. enable_signaling callback is used to provide sw signaling in case a cpu waiter is requested or no compatible hardware signaling could be used. The intention is to provide a userspace interface (presumably via eventfd) later, to be used in conjunction with dma-buf's mmap support for sw access to buffers (or for userspace apps that would prefer to do their own synchronization). v1: Original v2: After discussion w/ danvet and mlankhorst on #dri-devel, we decided that dma-fence didn't need to care about the sw->hw signaling path (it can be handled same as sw->sw case), and therefore the fence->ops can be simplified and more handled in the core. So remove the signal, add_callback, cancel_callback, and wait ops, and replace with a simple enable_signaling() op which can be used to inform a fence supporting hw->hw signaling that one or more devices which do not support hw signaling are waiting (and therefore it should enable an irq or do whatever is necessary in order that the CPU is notified when the fence is passed). v3: Fix locking fail in attach_fence() and get_fence() v4: Remove tie-in w/ dma-buf.. after discussion w/ danvet and mlankorst we decided that we need to be able to attach one fence to N dma-buf's, so using the list_head in dma-fence struct would be problematic. v5: [ Maarten Lankhorst ] Updated for dma-bikeshed-fence and dma-buf-manager. v6: [ Maarten Lankhorst ] I removed dma_fence_cancel_callback and some comments about checking if fence fired or not. This is broken by design. waitqueue_active during destruction is now fatal, since the signaller should be holding a reference in enable_signalling until it signalled the fence. Pass the original dma_fence_cb along, and call __remove_wait in the dma_fence_callback handler, so that no cleanup needs to be performed. v7: [ Maarten Lankhorst ] Set cb->func and only enable sw signaling if fence wasn't signaled yet, for example for hardware fences that may choose to signal blindly. v8: [ Maarten Lankhorst ] Tons of tiny fixes, moved __dma_fence_init to header and fixed include mess. dma-fence.h now includes dma-buf.h All members are now initialized, so kmalloc can be used for allocating a dma-fence. More documentation added. v9: Change compiler bitfields to flags, change return type of enable_signaling to bool. Rework dma_fence_wait. Added dma_fence_is_signaled and dma_fence_wait_timeout. s/dma// and change exports to non GPL. Added fence_is_signaled and fence_enable_sw_signaling calls, add ability to override default wait operation. v10: remove event_queue, use a custom list, export try_to_wake_up from scheduler. Remove fence lock and use a global spinlock instead, this should hopefully remove all the locking headaches I was having on trying to implement this. enable_signaling is called with this lock held. v11: Use atomic ops for flags, lifting the need for some spin_lock_irqsaves. However I kept the guarantee that after fence_signal returns, it is guaranteed that enable_signaling has either been called to completion, or will not be called any more. Add contexts and seqno to base fence implementation. This allows you to wait for less fences, by testing for seqno + signaled, and then only wait on the later fence. Add FENCE_TRACE, FENCE_WARN, and FENCE_ERR. This makes debugging easier. An CONFIG_DEBUG_FENCE will be added to turn off the FENCE_TRACE spam, and another runtime option can turn it off at runtime. v12: Add CONFIG_FENCE_TRACE. Add missing documentation for the fence->context and fence->seqno members. v13: Fixup CONFIG_FENCE_TRACE kconfig description. Move fence_context_alloc to fence. Simplify fence_later. Kill priv member to fence_cb. v14: Remove priv argument from fence_add_callback, oops! v15: Remove priv from documentation. Explicitly include linux/atomic.h. v16: Add trace events. Import changes required by android syncpoints. v17: Use wake_up_state instead of try_to_wake_up. (Colin Cross) Fix up commit description for seqno_fence. (Rob Clark) v18: Rename release_fence to fence_release. Move to drivers/dma-buf/. Rename __fence_is_signaled and __fence_signal to *_locked. Rename __fence_init to fence_init. Make fence_default_wait return a signed long, and fix wait ops too. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com> #use smp_mb__before_atomic() Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Daniel Vetter <daniel@ffwll.ch> Reviewed-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>