linux/drivers/gpu/drm
Daniel Vetter 1f83fee08d drm/i915: clear up wedged transitions
We have two important transitions of the wedged state in the current
code:

- 0 -> 1: This means a hang has been detected, and signals to everyone
  that they please get of any locks, so that the reset work item can
  do its job.

- 1 -> 0: The reset handler has completed.

Now the last transition mixes up two states: "Reset completed and
successful" and "Reset failed". To distinguish these two we do some
tricks with the reset completion, but I simply could not convince
myself that this doesn't race under odd circumstances.

Hence split this up, and add a new terminal state indicating that the
hw is gone for good.

Also add explicit #defines for both states, update comments.

v2: Split out the reset handling bugfix for the throttle ioctl.

v3: s/tmp/wedged/ sugested by Chris Wilson. Also fixup up a rebase
error which prevented this patch from actually compiling.

v4: To unify the wedged state with the reset counter, keep the
reset-in-progress state just as a flag. The terminally-wedged state is
now denoted with a big number.

v5: Add a comment to the reset_counter special values explaining that
WEDGED & RESET_IN_PROGRESS needs to be true for the code to be
correct.

v6: Fixup logic errors introduced with the wedged+reset_counter
unification. Since WEDGED implies reset-in-progress (in a way we're
terminally stuck in the dead-but-reset-not-completed state), we need
ensure that we check for this everywhere. The specific bug was in
wait_for_error, which would simply have timed out.

v7: Extract an inline i915_reset_in_progress helper to make the code
more readable. Also annote the reset-in-progress case with an
unlikely, to help the compiler optimize the fastpath. Do the same for
the terminally wedged case with i915_terminally_wedged.

Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2013-01-20 13:11:16 +01:00
..
ast Drivers: gpu: remove __dev* attributes. 2013-01-03 15:57:15 -08:00
cirrus Drivers: gpu: remove __dev* attributes. 2013-01-03 15:57:15 -08:00
exynos Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2013-01-08 16:08:10 -08:00
gma500 Drivers: gpu: remove __dev* attributes. 2013-01-03 15:57:15 -08:00
i2c drm/i2c: drm_connector_property -> drm_object_property 2012-11-30 10:20:12 -06:00
i810 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
i915 drm/i915: clear up wedged transitions 2013-01-20 13:11:16 +01:00
mga UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
mgag200 Drivers: gpu: remove __dev* attributes. 2013-01-03 15:57:15 -08:00
nouveau Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2013-01-08 16:08:10 -08:00
r128 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
radeon Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux 2013-01-08 16:08:10 -08:00
savage Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
shmobile Drivers: gpu: remove __dev* attributes. 2013-01-03 15:57:15 -08:00
sis UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
tdfx UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
tegra Revert "drm: tegra: protect DC register access with mutex" 2012-12-30 21:58:20 +10:00
ttm drm/ttm: fix fence locking in ttm_buffer_object_transfer 2013-01-08 18:35:31 +10:00
udl drm/udl: drm_connector_property -> drm_object_property 2012-11-30 10:20:11 -06:00
via UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
vmwgfx drm/ttm: remove no_wait_reserve, v3 2012-12-10 20:21:30 +10:00
ati_pcigart.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_agpsupport.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_auth.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_buffer.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_bufs.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_cache.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
drm_context.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_crtc_helper.c drm/doc: integrate crtc helper api into docbook 2012-11-28 20:19:58 +10:00
drm_crtc.c drm: remove legacy drm_connector_property fxns 2012-11-30 10:30:48 -06:00
drm_debugfs.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_dma.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_dp_helper.c drm/doc: add new dp helpers into drm DocBook 2012-11-28 20:26:53 +10:00
drm_drv.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
drm_edid_load.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
drm_edid_modes.h Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
drm_edid.c drm/edid: Add drm_rgb_quant_range_selectable() 2013-01-20 13:09:44 +01:00
drm_encoder_slave.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_fb_cma_helper.c drm: fb: cma: Fail gracefully on allocation failure 2012-10-23 10:14:58 +10:00
drm_fb_helper.c drm: remove legacy drm_connector_property fxns 2012-11-30 10:30:48 -06:00
drm_fops.c drm: set dev_mapping before calling drm_open_helper 2012-11-07 10:51:15 +10:00
drm_gem_cma_helper.c DRM: Add DRM GEM CMA helper 2012-09-18 12:28:21 +02:00
drm_gem.c mm: kill vma flag VM_RESERVED and mm->reserved_vm counter 2012-10-09 16:22:19 +09:00
drm_global.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_hashtab.c drm: Add a hash-tab rcu-safe API 2012-11-28 18:36:05 +10:00
drm_info.c drm/debugfs: remove redundant info from gem_names 2012-10-23 10:15:04 +10:00
drm_ioc32.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_ioctl.c drm: add support for monotonic vblank timestamps 2012-11-20 16:06:16 +10:00
drm_irq.c drm: hold event_lock while accessing vblank_event_list 2012-11-29 03:30:34 -08:00
drm_lock.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_memory.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_mm.c Merge tag 'drm-intel-next-2012-12-21' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2013-01-17 20:34:08 +10:00
drm_modes.c drm: Constify some function arguments 2012-11-07 10:09:16 +10:00
drm_pci.c drm/pci: add missing variable initialization 2012-11-29 18:20:31 +10:00
drm_platform.c drm: platform: Don't initialize driver-private data 2012-10-23 10:15:11 +10:00
drm_prime.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_proc.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_scatter.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_stub.c drm: add support for monotonic vblank timestamps 2012-11-20 16:06:16 +10:00
drm_sysfs.c drm: remove legacy drm_connector_property fxns 2012-11-30 10:30:48 -06:00
drm_trace_points.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_trace.h
drm_usb.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_vm.c mm: kill vma flag VM_RESERVED and mm->reserved_vm counter 2012-10-09 16:22:19 +09:00
Kconfig drm: Add NVIDIA Tegra20 support 2012-11-20 15:43:41 +10:00
Makefile drm: only build ati_pcigart if PCI enabled 2012-11-28 20:12:29 +10:00
README.drm

************************************************************
* For the very latest on DRI development, please see:      *
*     http://dri.freedesktop.org/                          *
************************************************************

The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).

The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:

    1. The DRM provides synchronized access to the graphics hardware via
       the use of an optimized two-tiered lock.

    2. The DRM enforces the DRI security policy for access to the graphics
       hardware by only allowing authenticated X11 clients access to
       restricted regions of memory.

    3. The DRM provides a generic DMA engine, complete with multiple
       queues and the ability to detect the need for an OpenGL context
       switch.

    4. The DRM is extensible via the use of small device-specific modules
       that rely extensively on the API exported by the DRM module.


Documentation on the DRI is available from:
    http://dri.freedesktop.org/wiki/Documentation
    http://sourceforge.net/project/showfiles.php?group_id=387
    http://dri.sourceforge.net/doc/

For specific information about kernel-level support, see:

    The Direct Rendering Manager, Kernel Support for the Direct Rendering
    Infrastructure
    http://dri.sourceforge.net/doc/drm_low_level.html

    Hardware Locking for the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/hardware_locking_low_level.html

    A Security Analysis of the Direct Rendering Infrastructure
    http://dri.sourceforge.net/doc/security_low_level.html