linux/drivers/gpu/drm
Daniel Vetter 23670b322c drm/i915: CPT+ pch transcoder workaround
We need to set the timing override chicken bit after fdi link training
has completed and before we enable the transcoder. We also have to
clear that bit again after disabling the pch transcoder.

See "Graphics BSpec: vol4g North Display Engine Registers [IVB],
Display Mode Set Sequence" and "Graphics BSpec: vol4h South Display
Engine Registers [CPT, PPT], South Display Engine Transcoder and FDI
Control, Transcoder Debug and DFT, TRANS_CHICKEN_2" bit 31:

"Workaround : Enable the override prior to enabling the transcoder.
Disable the override after disabling the transcoder."

While at it, use the _PIPE macro for the other TRANS_DP register.

v2: Keep the w/a as-is, but kill the original (but wrongly placed)
workaround introduced in

commit 3bcf603f6d
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date:   Wed Jul 27 11:51:40 2011 -0700

    drm/i915: apply timing generator bug workaround on CPT and PPT

and

commit d4270e57ef
Author: Jesse Barnes <jbarnes@virtuousgeek.org>
Date:   Tue Oct 11 10:43:02 2011 -0700

    drm/i915: export a CPT mode set verification function

Note that this old code has unconditionally set the w/a, which might
explain why fdi link training sometimes silently fails, and especially
why the auto-train did not seem to work properly.

v3: Paulo Zanoni pointed out that this workaround is also required on
the LPT PCH. And Arthur Ranyan confirmed that this workaround is
requierd for all ports on the pch, not just DP: The important part
is that the bit is set whenever the pch transcoder is enabled, and
that it is _not_ set while the fdi link is trained. It is also
important that the pch transcoder is fully disabled, i.e. we have to
wait for bit 30 to clear before clearing the w/a bit.

Hence move to workaround into enable/disable_transcoder, where the pch
transcoder gets enabled/disabled.

v4: Whitespace changes dropped.

v5: Don't run the w/a on IBX, we only need it on CPT/PPT and LPT.

v6:
- resolve conflicts with Paulo's big hsw vga rework
- s/!IBX/CPT since hsw paths are now all separate, and Paulo's patch
  to implement the equivalent w/a for LPT is already merged.

Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Paulo Zanoni <przanoni@gmail.com>
Cc: Arthur Ranyan <arthur.j.runyan@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com> (v5)
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org> (v5)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-11-11 23:51:30 +01:00
..
ast Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
cirrus Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
exynos fbdev updates for 3.7 2012-10-12 10:21:02 +09:00
gma500 mm: kill vma flag VM_RESERVED and mm->reserved_vm counter 2012-10-09 16:22:19 +09:00
i2c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
i810 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
i915 drm/i915: CPT+ pch transcoder workaround 2012-11-11 23:51:30 +01:00
mga UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
mgag200 Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
nouveau nouveau: fix warning on 32-bit build. 2012-10-16 16:40:53 +10:00
r128 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
radeon drm: extract drm_dp_max_lane_count helper 2012-10-22 22:56:43 +02:00
savage Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
shmobile drm: Renesas SH Mobile DRM driver 2012-09-18 12:28:22 +02:00
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
ttm mm: kill vma flag VM_RESERVED and mm->reserved_vm counter 2012-10-09 16:22:19 +09:00
udl mm: kill vma flag VM_RESERVED and mm->reserved_vm counter 2012-10-09 16:22:19 +09:00
via UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
vmwgfx Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
Kconfig drm: Renesas SH Mobile DRM driver 2012-09-18 12:28:22 +02:00
Makefile drm: rename drm_dp_i2c_helper.c to drm_dp_helper.c 2012-10-22 22:20:31 +02:00
README.drm
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.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
drm_crtc_helper.c drm: add helper to sort panels to the head of the connector list 2012-11-11 23:51:28 +01:00
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: extract dp link bw helpers 2012-10-22 22:34:47 +02:00
drm_drv.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
drm_edid.c Merge branch 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel into drm-next 2012-10-07 21:13:54 +10:00
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_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: Add DRM KMS/FB CMA helper 2012-09-18 12:28:21 +02:00
drm_fb_helper.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
drm_fops.c Prepared for main script 2012-10-03 13:45:43 -07:00
drm_gem.c mm: kill vma flag VM_RESERVED and mm->reserved_vm counter 2012-10-09 16:22:19 +09:00
drm_gem_cma_helper.c DRM: Add DRM GEM CMA helper 2012-09-18 12:28:21 +02:00
drm_global.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_hashtab.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_info.c drm: fix warning on 32-bit. 2012-10-16 10:28:21 +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 Prepared for main script 2012-10-03 13:45:43 -07:00
drm_irq.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-10-03 23:29:23 -07:00
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 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_modes.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_pci.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_platform.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
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 UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_sysfs.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
drm_trace.h
drm_trace_points.c UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/ 2012-10-02 18:01:07 +01:00
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

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