linux/drivers/gpu/drm
Daniel Vetter 59de3295ad drm/i915: enable semaphores on gen6 if dmar is not active
Inspired by the recent ppgtt regression report, where switching of
dmar only for the gpu seems to fix things completely, I've looked
again at the semaphores+vt-d situation.

Contrary to my earlier testing a few months back my system is now
stable with dmar disabled for the igd, and not only when disabling
dmar completely.

So I'm rather hopeful that all our recent fixes for snb have changed
things for code and it's time to try enabling semaphores again. We've
also had issues with enabling semaphores which are not vt-d related,
but I guess these are all fixed by the autoreport-disabling and lazy
request fix. And there's only one way to find out whether there are
still other issues ...

When I've tried to apply this patch I've noticed that semaphores on
gen6 have already silently been enabled in

commit 2911a35b2e
Author: Ben Widawsky <ben@bwidawsk.net>
Date:   Thu Apr 5 14:47:36 2012 -0700

    drm/i915: use semaphores for the display plane

Fix this up by only checking whether dmar is enabled on the gfx (not
on the entire system).

Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-05-10 10:34:39 +02:00
..
exynos Merge branch 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-2.6-samsung into drm-fixes 2012-04-27 08:20:35 +01:00
gma500 Merge branch 'for-airlied' of git://people.freedesktop.org/~danvet/drm-intel into drm-core-next 2012-05-07 16:09:35 +01:00
i2c drm: add convenience function to create an range property 2012-02-09 10:15:25 +00:00
i810 kill mm argument of vm_munmap() 2012-04-21 01:58:20 -04:00
i915 drm/i915: enable semaphores on gen6 if dmar is not active 2012-05-10 10:34:39 +02:00
mga drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
nouveau nouveau: initialise has_optimus variable. 2012-05-03 09:30:58 +01:00
r128 drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
radeon Merge branch 'for-airlied' of git://people.freedesktop.org/~danvet/drm-intel into drm-core-next 2012-05-07 16:09:35 +01:00
savage drm/savage: fix integer overflows in savage_bci_cmdbuf() 2012-04-10 10:22:51 +01:00
sis drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
tdfx drm: Make the per-driver file_operations struct const 2011-11-11 11:14:47 +00:00
ttm Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-03-22 13:08:22 -07:00
udl mm, drm/udl: fixup vma flags on mmap 2012-04-02 11:08:17 +01:00
via drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
vmwgfx Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-03-22 13:08:22 -07:00
ati_pcigart.c
drm_agpsupport.c
drm_auth.c drm: Fix authentication kernel crash 2012-01-25 09:27:45 +00:00
drm_buffer.c
drm_bufs.c VM: add "vm_mmap()" helper function 2012-04-20 17:29:13 -07:00
drm_cache.c Merge branch 'drm-intel-next' of git://people.freedesktop.org/~danvet/drm-intel into drm-core-next 2012-04-12 10:27:01 +01:00
drm_context.c drm: Unify and fix idr error handling 2012-04-24 09:50:20 +01:00
drm_crtc_helper.c drm: Move drm_format_num_planes() to drm_crtc.c 2012-04-20 12:37:11 +01:00
drm_crtc.c Merge branch 'for-airlied' of git://people.freedesktop.org/~danvet/drm-intel into drm-core-next 2012-05-07 16:09:35 +01:00
drm_debugfs.c drm: serialize access to list of debugfs files 2011-11-11 11:05:19 +00:00
drm_dma.c
drm_dp_i2c_helper.c
drm_drv.c drm: base prime/dma-buf support (v5) 2012-03-30 11:52:44 +01:00
drm_edid_load.c drm/edid: fix collision between two patches breaking build 2012-04-30 07:26:16 +01:00
drm_edid_modes.h drm: replace open-coded ARRAY_SIZE with macro 2012-04-20 13:12:16 +01:00
drm_edid.c drm: Store vendor IDs directly in the EDID quirk structure 2012-04-27 08:25:13 +01:00
drm_encoder_slave.c
drm_fb_helper.c drm/edid: Allow drm_mode_find_dmt to hunt for reduced-blanking modes 2012-04-20 12:57:03 +01:00
drm_fops.c drm: Releasing FBs before releasing GEM objects during drm_release 2012-04-19 14:40:41 +01:00
drm_gem.c drm: Unify and fix idr error handling 2012-04-24 09:50:20 +01:00
drm_global.c
drm_hashtab.c
drm_info.c
drm_ioc32.c drivers/gpu/drm/drm_ioc32.c: initialize all fields 2012-02-03 09:47:32 +00:00
drm_ioctl.c drm: add some caps for userspace to discover more info for dumb KMS driver (v2) 2012-02-16 18:35:11 +00:00
drm_irq.c drm: remove unused code 2012-02-29 10:18:29 +00:00
drm_lock.c drm: add missing exports for i810 driver. 2011-12-22 19:09:01 +00:00
drm_memory.c drm: remove unused code 2012-02-29 10:18:29 +00:00
drm_mm.c
drm_modes.c drm: Add drm_mode_copy() 2012-03-15 09:52:51 +00:00
drm_pci.c drm: move pci bus master enable into driver. 2012-02-16 18:31:07 +00:00
drm_platform.c drm: cope with platformdev->id == -1 2012-03-07 14:03:40 +00:00
drm_prime.c drm: base prime/dma-buf support (v5) 2012-03-30 11:52:44 +01:00
drm_proc.c
drm_scatter.c
drm_stub.c drm: Unify and fix idr error handling 2012-04-24 09:50:20 +01:00
drm_sysfs.c drm/sysfs: protect sysfs removal code against being run twice. 2012-03-15 13:35:31 +00:00
drm_trace_points.c
drm_trace.h
drm_usb.c drm/usb: fix module license on drm/usb layer. 2012-04-19 09:33:32 +01:00
drm_vm.c drm: add core support for unplugging a device (v2) 2012-03-15 13:35:33 +00:00
Kconfig drm: base prime/dma-buf support (v5) 2012-03-30 11:52:44 +01:00
Makefile drm: base prime/dma-buf support (v5) 2012-03-30 11:52:44 +01:00
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