linux/drivers/gpu/drm
Chris Wilson d9e86c0ee6 drm/i915: Pipelined fencing [infrastructure]
With this change, every batchbuffer can use all available fences (save
pinned and scanout, of course) without ever stalling the gpu!

In theory. Currently the actual pipelined update of the register is
disabled due to some stability issues. However, just the deferred update
is a significant win.

Based on a series of patches by Daniel Vetter.

The premise is that before every access to a buffer through the GTT we
have to declare whether we need a register or not. If the access is by
the GPU, a pipelined update to the register is made via the ringbuffer,
and we track the last seqno of the batches that access it. If by the
CPU we wait for the last GPU access and update the register (either
to clear or to set it for the current buffer).

One advantage of being able to pipeline changes is that we can defer the
actual updating of the fence register until we first need to access the
object through the GTT, i.e. we can eliminate the stall on set_tiling.
This is important as the userspace bo cache does not track the tiling
status of active buffers which generate frequent stalls on gen3 when
enabling tiling for an already bound buffer.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2010-12-02 10:07:05 +00:00
..
i2c drm/i2c/ch7006: Don't use POWER_LEVEL_FULL_POWER_OFF on early chip versions. 2010-08-09 15:16:23 +10:00
i810 Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-10-26 18:57:59 -07:00
i830 Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-10-26 18:57:59 -07:00
i915 drm/i915: Pipelined fencing [infrastructure] 2010-12-02 10:07:05 +00:00
mga Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-10-26 18:57:59 -07:00
nouveau nouveau: Acknowledge HPD irq in handler, not bottom half 2010-11-18 14:39:07 +10:00
r128 Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-10-26 18:57:59 -07:00
radeon drm/radeon/kms: i2c s/sprintf/snprintf/g for safety 2010-11-19 09:27:48 +10:00
savage Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-10-26 18:57:59 -07:00
sis Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-10-26 18:57:59 -07:00
tdfx Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-10-26 18:57:59 -07:00
ttm drm/ttm: Fix up a theoretical deadlock 2010-11-18 15:00:42 +10:00
via drivers/gpu: Use vzalloc 2010-11-09 13:41:35 +10:00
vmwgfx drm/vmwgfx: Fix up an error path during bo creation 2010-11-18 14:56:47 +10:00
ati_pcigart.c drm/radeon: Fix pci_map_page() error checking 2010-08-12 09:38:29 +10:00
drm_agpsupport.c drm: kill drm_agp_chipset_flush 2010-11-23 20:14:44 +00:00
drm_auth.c
drm_buffer.c drm: fix trivial coding errors 2010-09-24 10:10:23 +10:00
drm_bufs.c DRM: Replace kmalloc/memset combos with kzalloc 2010-08-12 09:12:30 +10:00
drm_cache.c
drm_context.c drm: kill context_ctor callback 2010-08-30 09:38:25 +10:00
drm_crtc_helper.c drivers/gpu/drm: Update WARN uses 2010-11-09 13:37:15 +10:00
drm_crtc.c drm: vmwgfx: Add a struct drm_file parameter to the dirty framebuffer callback 2010-10-06 11:29:41 +10:00
drm_debugfs.c drm: Move the GTT accounting to i915 2010-10-01 14:45:20 +01:00
drm_dma.c
drm_dp_i2c_helper.c
drm_drv.c Merge branch 'drm-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 2010-10-26 18:57:59 -07:00
drm_edid_modes.h drm/edid: Split mode lists out to their own header for readability 2010-08-10 10:47:00 +10:00
drm_edid.c DRM: ignore invalid EDID extensions 2010-11-09 13:34:14 +10:00
drm_encoder_slave.c drm/kms: Simplify setup of the initial I2C encoder config. 2010-08-05 09:37:45 +10:00
drm_fb_helper.c drm, kdb, kms: Change mode_set_base_atomic() enter argument to be an enum 2010-10-19 14:13:33 +10:00
drm_fops.c BKL: remove extraneous #include <smp_lock.h> 2010-11-17 08:59:32 -08:00
drm_gem.c Merge remote branch 'korg/drm-fixes' into drm-vmware-next 2010-10-06 11:10:48 +10:00
drm_global.c drm: move ttm global code to core drm 2010-08-04 09:46:06 +10:00
drm_hashtab.c
drm_info.c Merge remote branch 'korg/drm-fixes' into drm-vmware-next 2010-10-06 11:10:48 +10:00
drm_ioc32.c
drm_ioctl.c drm: Fix support for PCI domains 2010-08-10 08:20:20 +10:00
drm_irq.c Merge branch 'drm-tracepoints' into drm-testing 2010-07-07 18:38:44 +10:00
drm_lock.c drm: readd drm_lock_free in drm_unlock 2010-09-26 13:35:49 +10:00
drm_memory.c drm: kill agp indirection mess 2010-08-30 09:44:40 +10:00
drm_mm.c drm_mm: add support for range-restricted fair-lru scans 2010-10-27 23:31:04 +01:00
drm_modes.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2010-10-24 13:41:39 -07:00
drm_pci.c drm: fix race between driver loading and userspace open. 2010-09-14 20:39:04 +10:00
drm_platform.c drm: fix race between driver loading and userspace open. 2010-09-14 20:39:04 +10:00
drm_proc.c drm: Move the GTT accounting to i915 2010-10-01 14:45:20 +01:00
drm_scatter.c drm: don't export drm_sg_alloc 2010-08-30 09:37:43 +10:00
drm_sman.c
drm_stub.c drm: kill dev->timer 2010-08-30 09:44:54 +10:00
drm_sysfs.c drm: Use a nondestructive mode for output detect when polling 2010-09-13 20:29:11 +10:00
drm_trace_points.c
drm_trace.h
drm_vm.c Merge remote branch 'korg/drm-fixes' into drm-vmware-next 2010-10-06 11:10:48 +10:00
Kconfig BKL: introduce CONFIG_BKL. 2010-10-21 15:44:13 +02:00
Makefile drm: replace drawable ioctl by noops 2010-08-30 09:39:11 +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