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2014-11-21reservation: update api and add some helpersMaarten Lankhorst1-0/+1
Move the list of shared fences to a struct, and return it in reservation_object_get_list(). Add reservation_object_get_excl to get the exclusive fence. Add reservation_object_reserve_shared(), which reserves space in the reservation_object for 1 more shared fence. reservation_object_add_shared_fence() and reservation_object_add_excl_fence() are used to assign a new fence to a reservation_object pointer, to complete a reservation. Changes since v1: - Add reservation_object_get_excl, reorder code a bit. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Daniel Vetter <daniel@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21seqno-fence: Hardware dma-buf implementation of fencing (v6)Maarten Lankhorst1-0/+2
This type of fence can be used with hardware synchronization for simple hardware that can block execution until the condition (dma_buf[offset] - value) >= 0 has been met when WAIT_GEQUAL is used, or (dma_buf[offset] != 0) has been met when WAIT_NONZERO is set. A software fallback still has to be provided in case the fence is used with a device that doesn't support this mechanism. It is useful to expose this for graphics cards that have an op to support this. Some cards like i915 can export those, but don't have an option to wait, so they need the software fallback. I extended the original patch by Rob Clark. v1: Original v2: Renamed from bikeshed to seqno, moved into dma-fence.c since not much was left of the file. Lots of documentation added. v3: Use fence_ops instead of custom callbacks. Moved to own file to avoid circular dependency between dma-buf.h and fence.h v4: Add spinlock pointer to seqno_fence_init v5: Add condition member to allow wait for != 0. Fix small style errors pointed out by checkpatch. v6: Move to a separate file. Fix up api changes in fences. 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: Rob Clark <robdclark@gmail.com> #v4 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21fence: dma-buf cross-device synchronization (v18)Maarten Lankhorst1-0/+2
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> Signed-off-by: Chanho Park <chanho61.park@samsung.com> Conflicts: drivers/base/Kconfig Change-Id: Ie62c8c33a0cb7ca3df596f47ef328c33c4468139
2014-11-21dma-buf: move to drivers/dma-bufMaarten Lankhorst1-2/+1
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Acked-by: Sumit Semwal <sumit.semwal@linaro.org> Acked-by: Daniel Vetter <daniel@ffwll.ch> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-21reservation: cross-device reservation support, v4Maarten Lankhorst1-0/+2
This adds support for a generic reservations framework that can be hooked up to ttm and dma-buf and allows easy sharing of reservations across devices. The idea is that a dma-buf and ttm object both will get a pointer to a struct reservation_object, which has to be reserved before anything is done with the contents of the dma-buf. Changes since v1: - Fix locking issue in ticket_reserve, which could cause mutex_unlock to be called too many times. Changes since v2: - All fence related calls and members have been taken out for now, what's left is the bare minimum to be useful for ttm locking conversion. Changes since v3: - Removed helper functions too. The documentation has an example implementation for locking. With the move to ww_mutex there is no need to have much logic any more. Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com> Reviewed-by: Jerome Glisse <jglisse@redhat.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-04-03tty: Documentation: fix a path in a DocBook templateGuennadi Liakhovetski1-1/+1
A wrong path to a driver breaks DocBook built. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Acked-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-02Merge branch 'for-next' of git://gitorious.org/kernel-hsi/kernel-hsiLinus Torvalds1-0/+17
Pull HSI (High Speed Synchronous Serial Interface) framework from Carlos Chinea: "The High Speed Synchronous Serial Interface (HSI) is a serial interface mainly used for connecting application engines (APE) with cellular modem engines (CMT) in cellular handsets. The framework is currently being used for some people and we would like to see it integrated into the kernel for 3.3. There is no HW controller drivers in this pull, but some people have already some of them pending which they would like to push as soon as this integrated. I am also working on the acceptance for an TI OMAP one, based on a compatible legacy version of the interface called SSI." Ok, so it didn't get into 3.3, but here it is pulled into 3.4. Several people piped up to say "yeah, we want this". * 'for-next' of git://gitorious.org/kernel-hsi/kernel-hsi: HSI: hsi_char: Update ioctl-number.txt HSI: Add HSI API documentation HSI: hsi_char: Add HSI char device kernel configuration HSI: hsi_char: Add HSI char device driver HSI: hsi: Introducing HSI framework
2012-02-01docbook: fix fatal errors in device-drivers docbook and add DMA Management ↵Randy Dunlap1-2/+10
section Fix 2 fatal errors in the device-drivers docbook. Also add some missing files from drivers/base/; since several of these are DMA-related, add a section for DMA Management. docproc: drivers/base/sys.c: No such file or directory docproc: drivers/tty/serial/8250.c: No such file or directory Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-23docbook: fix sched source file names in device-drivers bookRandy Dunlap1-1/+3
Fix warning since kernel scheduler functions and kernel-doc notation were moved to other files. docproc: lnx-33-rc1/kernel/sched.c: No such file or directory Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-23docbook: don't use serial_core.h in device-drivers bookRandy Dunlap1-1/+0
Fix new kernel-doc warning. This file no longer contains kernel-doc comments. Warning(include/linux/serial_core.h): no structured comments found Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Cc: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-01-05HSI: Add HSI API documentationCarlos Chinea1-0/+17
Add an entry for HSI in the device-drivers section of the kernel documentation. Signed-off-by: Carlos Chinea <carlos.chinea@nokia.com>
2011-05-06driver core: Add the device driver-model structures to kerneldocWanlong Gao1-3/+3
Add the comments to the structure bus_type, device_driver, device, class to device.h for generating the driver-model kerneldoc. With another patch these all removed from the files in Documentation/driver-model/ since they are out of date. That will keep things up to date and provide a better way to document this stuff. Signed-off-by: Wanlong Gao <wanlong.gao@gmail.com> Acked-by: Harry Wei <harryxiyou@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-22docbook: fix broken serial to tty/serial movementRandy Dunlap1-2/+2
Fix move of drivers/serial/ to drivers/tty/, where it broke one of the docbook files: docproc: drivers/serial/serial_core.c: No such file or directory Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-16Input: include MT library as source for kerneldocDmitry Torokhov1-0/+4
Signed-off-by: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
2010-10-26docbook: add more wait/wake/completion to device-drivers docbookRandy Dunlap1-0/+5
Add more wait, wake, and completion interfaces to the device-drivers docbook. Fix kernel-doc notation in the added files. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-11docbook: skip files with no docs since they generate scary warningsRandy Dunlap1-1/+0
Fix docbook templates that reference files that do not contain the expected kernel-doc notation. Fixes these warnings: Warning(arch/x86/include/asm/unaligned.h): no structured comments found Warning(lib/vsprintf.c): no structured comments found These cause errors in the generated html output, like below, so drop these lines. Name arch/x86/include/asm/unaligned.h - Document generation inconsistency Oops Warning The template for this document tried to insert the structured comment from the file arch/x86/include/asm/unaligned.h at this point, but none was found. This dummy section is inserted to allow generation to continue. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-05Driver core: reduce duplicated code for platform_device creationUwe Kleine-König1-0/+1
This makes the two similar functions platform_device_register_simple and platform_device_register_data one line inline functions using a new generic function platform_device_register_resndata. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-03docbook: fix errors from x86 headers mergerRandy Dunlap1-1/+1
Fix docbook errors for x86 headers that were recently merged: docproc: arch/x86/include/asm/atomic_32.h: No such file or directory docproc: arch/x86/include/asm/io_32.h: No such file or directory Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Brian Gerst <brgerst@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-07Input: add generic support for sparse keymapsDmitry Torokhov1-0/+4
More and more devices choose to reimplement support for sparse keymaps first introduced by wistron driver. Move it into a library module so it can be easily used by interested parties. Reviewed-by: Anisse Astier <anisse@astier.eu> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-11-20Input: input-polldev, matrix-keypad - include in kernel docDmitry Torokhov1-0/+9
Make sure that polled input device and matrix keypad APIs are included with the rest of input API when generating kernel documentation. Also description of absres was missing as well. Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-02-22docbook: split kernel-api for device-driversRandy Dunlap1-0/+418
The kernel-api docbook was much larger than any of the others, so processing it took longer and needed some docbook extras in some cases, so split it into kernel-api (infrastructure etc.) and device drivers/device subsystems. This allows these docbooks to be generated in parallel. (This reduced the docbook processing time on my 4-proc system with make -j4 from about 5min:16sec to about 2min:01sec.) The chapters that were moved from kernel-api to device-drivers are: Driver Basics Device drivers infrastructure Parallel Port Devices Message-based devices Sound Devices 16x50 UART Driver Frame Buffer Library Input Subsystem Serial Peripheral Interface (SPI) I2C and SMBus Subsystem Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>