linux_dsm_epyc7002/drivers/gpu/drm
Daniel Vetter fba92150aa drm/i915: rip out early dp port write for gm45/ilk
It's bogus.

If I've followed the history of this piece of code correctly, i.e. the
initial register write with the following vblank wait, this goes all
the way back to the original enabling of DP support in

commit a4fc5ed698
Author: Keith Packard <keithp@keithp.com>
Date:   Tue Apr 7 16:16:42 2009 -0700

    drm/i915: Add Display Port support

Unfortunately it seems to be nothing more than glorified duct-tape and
sometimes actively harmful. Adam Jackson noticed this for CPT
platforms with

commit e85194641b
Author: Adam Jackson <ajax@redhat.com>
Date:   Thu Jul 21 17:48:38 2011 -0400

    drm/i915/dp: Don't turn CPT DP ports on too early

Unfortunately this kept the code around for ilk and gm45.

The specific failure case I'm seeing here is that after a dpms off/on
cycle we have the bits from the last link training (hopefully
successful link training) set in intel_dp->DP. This is requiered so
that complete_link_train can enable the port with the right tuning
values.

Unfortunately writing these again to the disabled port at dpms on time
kills the port somehow until it's disabled - dp link training fails in
an endless loop without this patch on my mobile ilk and gm45.

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=51493
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2012-09-20 14:23:02 +02:00
..
ast drm/ast: fix EDID memory leak 2012-08-24 09:37:09 +10:00
cirrus drm/cirrus: Remove unused validate_sequence 2012-08-24 09:34:46 +10:00
exynos drm: remove the raw_edid field from struct drm_display_info 2012-08-24 09:37:36 +10:00
gma500 gma500: Remove unused variable 2012-09-13 11:40:05 +10:00
i2c drm/i2c/ch7006: Convert to dev_pm_ops 2012-08-24 09:56:08 +10:00
i810 drm: kill dma queue support 2012-07-19 22:50:55 -04:00
i915 drm/i915: rip out early dp port write for gm45/ilk 2012-09-20 14:23:02 +02:00
mga drm: kill reclaim_buffers callback 2012-07-19 22:50:28 -04:00
mgag200 drm: remove the raw_edid field from struct drm_display_info 2012-08-24 09:37:36 +10:00
nouveau drm: use %*ph to dump small buffers 2012-09-13 11:28:30 +10:00
r128 drm: kill reclaim_buffers callback 2012-07-19 22:50:28 -04:00
radeon drm: use %*ph to dump small buffers 2012-09-13 11:28:30 +10:00
savage drm/savage: clean up reclaim_buffers 2012-07-19 22:50:16 -04:00
shmobile drm: Renesas SH Mobile DRM driver 2012-09-18 12:28:22 +02:00
sis drm/sis: fixup sis_mm ioctl structs 2012-07-19 22:51:58 -04:00
tdfx drm: kill reclaim_buffers callback 2012-07-19 22:50:28 -04:00
ttm drm: Handle io prot correctly for MIPS. 2012-08-24 09:41:05 +10:00
udl drm: use %*ph to dump small buffers 2012-09-13 11:28:30 +10:00
via drm/via: clean up reclaim_buffers 2012-07-19 22:48:28 -04:00
vmwgfx vmwgfx: remove useless set memory to zero use memset() 2012-09-13 11:34:34 +10:00
ati_pcigart.c
drm_agpsupport.c
drm_auth.c
drm_buffer.c
drm_bufs.c drm: kill dma queue support 2012-07-19 22:50:55 -04:00
drm_cache.c drm/i915: Replace the array of pages with a scatterlist 2012-09-20 14:22:57 +02:00
drm_context.c
drm_crtc_helper.c drm: Don't initialize local ret variable when not needed 2012-05-22 10:32:58 +01:00
drm_crtc.c drm: Add NV24 and NV42 pixel formats 2012-09-18 12:28:21 +02:00
drm_debugfs.c drm: kill dma queue support 2012-07-19 22:50:55 -04:00
drm_dma.c drm: kill dma queue support 2012-07-19 22:50:55 -04:00
drm_dp_i2c_helper.c
drm_drv.c drm: make buffer management work without DRM_MASTER 2012-09-13 11:19:44 +10:00
drm_edid_load.c drm/edid: limit printk when facing bad edid 2012-09-17 11:16:40 +10:00
drm_edid_modes.h drm: consistently name interlaced modes 2012-09-13 11:21:03 +10:00
drm_edid.c drm/edid: limit printk when facing bad edid 2012-09-17 11:16:40 +10:00
drm_encoder_slave.c
drm_fb_cma_helper.c DRM: Add DRM KMS/FB CMA helper 2012-09-18 12:28:21 +02:00
drm_fb_helper.c drm/fb helper: don't call drm_helper_connector_dpms directly 2012-09-08 00:51:15 +02:00
drm_fops.c drm: track dev_mapping in more robust and flexible way 2012-07-25 14:09:30 +10:00
drm_gem_cma_helper.c DRM: Add DRM GEM CMA helper 2012-09-18 12:28:21 +02:00
drm_gem.c drm: Add colouring to the range allocator 2012-07-16 05:59:37 +10:00
drm_global.c
drm_hashtab.c
drm_info.c drm: kill dma queue support 2012-07-19 22:50:55 -04:00
drm_ioc32.c
drm_ioctl.c drm/prime: expose capability flags for userspace. 2012-05-18 11:12:16 +01:00
drm_irq.c drm: Add missing static storage class specifier in drm_irq.c file 2012-08-24 10:00:56 +10:00
drm_lock.c drm: ditch strange DRIVER_DMA_QUEUE only error bail-out 2012-07-19 22:50:47 -04:00
drm_memory.c
drm_mm.c drm: Add colouring to the range allocator 2012-07-16 05:59:37 +10:00
drm_modes.c drm: Remove two unused fields from struct drm_display_mode 2012-08-22 09:27:27 +10:00
drm_pci.c drm/pci: add support for getting the supported link bw. 2012-07-19 22:29:25 -04:00
drm_platform.c
drm_prime.c drm/prime: add exported buffers to current fprivs imported buffer list (v2) 2012-05-23 10:46:03 +01:00
drm_proc.c drm: Add missing static storage class specifiers in drm_proc.c file 2012-08-22 09:30:00 +10:00
drm_scatter.c
drm_stub.c drm: Don't initialize local ret variable when not needed 2012-05-22 10:32:58 +01:00
drm_sysfs.c drm: fail gracefully when proc isn't setup. 2012-07-16 05:57:03 +10:00
drm_trace_points.c
drm_trace.h
drm_usb.c
drm_vm.c drm: Remove unnecessary test for ARM. 2012-09-13 11:28:39 +10:00
Kconfig drm: Renesas SH Mobile DRM driver 2012-09-18 12:28:22 +02:00
Makefile drm: Renesas SH Mobile DRM driver 2012-09-18 12:28:22 +02:00
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