Commit Graph

737777 Commits

Author SHA1 Message Date
Rex Zhu
af264d0245 drm/amd/pp: Refine code in powerplay for Cz/Vega10
Add dpm check functions on CZ/Vega10 to smu backend
function table.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:40 -05:00
Rex Zhu
d246cd53fd drm/amd/pp: Remove dead error checking code on Vega10
when smu failed, print out the error info immediately
for debug. smum_send_msg_to_smu always return true,
so no need to check return value.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:40 -05:00
Rex Zhu
baeb7721b1 drm/amd/pp: Add debug info when smu failed on Vega10
When smu msssage failed, print out return value in dmesg.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:39 -05:00
Rex Zhu
bd58c48c10 drm/amd/pp: Remove duplicated vega10_is_smc_ram_running calls
Avoid conflicts in reading the same register mmPCIE_INDEX2
with other clients

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:39 -05:00
Corentin Labbe
103a4b1d48 drm/amd: Remove inclusion of non-existing include directories
This patch fix the following build warnings:
  CC [M]  drivers/gpu/drm/amd/amdgpu/amdgpu_drv.o
cc1: warning: ../display/: No such file or directory [-Wmissing-include-dirs]
cc1: warning: ../display/include: No such file or directory [-Wmissing-include-dirs]
  CC [M]  drivers/gpu/drm/amd/amdgpu/amdgpu_device.o
cc1: warning: ../display/: No such file or directory [-Wmissing-include-dirs]
cc1: warning: ../display/include: No such file or directory [-Wmissing-include-dirs]
[...]
This warning is shown for each file in amdgpu directory, so it spams a lot.

Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:38 -05:00
Corentin Labbe
fbb3156218 drm/amd: remove inclusion of non-existing scheduler directory
The scheduler directory was removed via commit 1b1f42d8fd ("drm: move amd_gpu_scheduler into common location")
Remove it from include path.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:38 -05:00
Ben Crocker
bcb0b981c5 drm/radeon: insist on 32-bit DMA for Cedar on PPC64/PPC64LE
In radeon_device_init, set the need_dma32 flag for Cedar chips
(e.g. FirePro 2270).  This fixes, or at least works around, a bug
on PowerPC exposed by last year's commits

8e3f1b1d82 (Russell Currey)

and

253fd51e2f (Alistair Popple)

which enabled the 64-bit DMA iommu bypass.

This caused the device to freeze, in some cases unrecoverably, and is
the subject of several bug reports internal to Red Hat.

Signed-off-by: Ben Crocker <bcrocker@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2018-02-26 23:09:38 -05:00
Thierry Reding
421334a847 drm/amdgpu: Remove duplicate setting of ->need_swiotlb
There's no need to set this before the number of DMA bits has been
properly determined.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:37 -05:00
Rex Zhu
3214e02199 drm/amd/pp: Add a pp feature mask bit for AutoWattman feature
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:37 -05:00
Rex Zhu
3d2fc0813f drm/amdgpu: Change default value of module parameter amdgpu_pp_feature_mask
Currently all pp features are enabled by default except
OVERDRIVE

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:37 -05:00
Eric Huang
472c89fcd5 drm/amd/powerplay: fix thermal interrupts on vega10
a bug in programming thermal interrupt register masks out
interrupts and driver cannot receive interrupts. Setting
0 to mask bits will fix it.

Signed-off-by: Eric Huang <JinHuiEric.Huang@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:36 -05:00
Rex Zhu
eda9a4eb15 drm/amdgpu: Add query vram width in CGS query system info
powerplay need vram width to set default mclk optimization
settings(uphyst/downhyst/activity threshold)

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:36 -05:00
Christian König
92e71b0676 drm/amdgpu: use the TTM dummy page instead of allocating one
We have a global dummy page in TTM, use that one instead of allocating a
new one.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:36 -05:00
Rex Zhu
a02497b732 drm/amd/pp: Fix bug that dpm level was not really locked
Lock the dpm levels when we use SW method to modify
the dpm tables directly to avoid a possible race
with the smu.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:35 -05:00
Rex Zhu
952e5daa25 drm/amd/pp: Fix error handling when smu return failed on Vega10.
Clamp the clock index to a valid range when reading it back

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:35 -05:00
Roger He
40d5250dbb drm/ttm: set TTM_OPT_FLAG_FORCE_ALLOC in ttm_bo_force_list_clean
Because ttm_bo_force_list_clean() is only called on two occasions:
1. By ttm_bo_evict_mm() during suspend.
2. By ttm_bo_clean_mm() when the driver unloads.
On both cases we absolutely don't want any memory allocation failure.

Signed-off-by: Roger He <Hongbo.He@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:34 -05:00
Roger He
aa7662b67b drm/ttm: add bit flag TTM_OPT_FLAG_FORCE_ALLOC
set TTM_OPT_FLAG_FORCE_ALLOC when we are servicing for page
fault routine.

for ttm_mem_global_reserve if in page fault routine, allow the gtt
pages reservation always. because page fault routing already grabbed
system memory and the allowance of this exception is harmless.
Otherwise, it will trigger OOM killer.

will be used later.

v2: set the FORCE_ALLOC always
v3: minor refine

Signed-off-by: Roger He <Hongbo.He@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:34 -05:00
Roger He
d330fca115 drm/ttm: use bit flag to replace allow_reserved_eviction in ttm_operation_ctx
for saving memory and more bit flag can be used in future

Signed-off-by: Roger He <Hongbo.He@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:34 -05:00
Arnd Bergmann
c02216acf4 radeon: hide pointless #warning when compile testing
In randconfig testing, we sometimes get this warning:

drivers/gpu/drm/radeon/radeon_object.c: In function 'radeon_bo_create':
drivers/gpu/drm/radeon/radeon_object.c:242:2: error: #warning Please enable CONFIG_MTRR and CONFIG_X86_PAT for better performance thanks to write-combining [-Werror=cpp]
 #warning Please enable CONFIG_MTRR and CONFIG_X86_PAT for better performance \

This is rather annoying since almost all other code produces no build-time
output unless we have found a real bug. We already fixed this in the
amdgpu driver in commit 31bb90f1cd ("drm/amdgpu: shut up #warning for
compile testing") by adding a CONFIG_COMPILE_TEST check last year and
agreed to do the same here, but both Michel and I then forgot about it
until I came across the issue again now.

For stable kernels, as this is one of very few remaining randconfig
warnings in 4.14.

Cc: stable@vger.kernel.org
Link: https://patchwork.kernel.org/patch/9550009/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:33 -05:00
Christian König
ec92937056 drm/ttm: set page mapping during allocation
To aid debugging set the page mapping during allocation instead of
during VM faults.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Roger He <Hongbo.He@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-26 23:09:33 -05:00
Alex Deucher
9aff8b2ae7 Revert "drm/radeon/pm: autoswitch power state when in balanced mode"
This reverts commit 1c331f75aa.

Breaks resume on some systems.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100759
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2018-02-20 16:27:16 -05:00
Christian König
a489727fcc drm/radeon: use drm_gem_private_object_init
We use our own backing store and don't need the shmem file.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-20 14:40:33 -05:00
Christian König
c06cc6f760 drm/amdgpu: use drm_gem_private_object_init
We use our own backing store and don't need the shmem file.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-20 14:40:22 -05:00
Christian König
9021d2edd2 drm/amdgpu: mitigate workaround for i915
To be able to use DRI_PRIME with amdgpu and i915 we add all our fences
only as exclusive ones.

Disable that behavior when sharing between amdgpu itself cause it
hinders concurrent execution.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-20 14:40:13 -05:00
Christian König
5a13761fa6 drm/amdgpu: implement amdgpu_gem_map_(attach/detach)
Instead of the pin/unpin callback implement the attach/detach ones.

Functional identical, but allows us access to the attachment.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-20 14:40:03 -05:00
Alex Deucher
d821792171 drm/amdgpu/powerplay/smu7: drop refresh rate checks for mclk switching
The logic has moved to cgs.  mclk switching with DC at higher refresh
rates should work.

Reviewed-by: Eric Huang <JinhuiEric.Huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
2018-02-19 14:20:23 -05:00
Alex Deucher
7a572b1eda drm/amdgpu/cgs: add refresh rate checking to non-DC display code
Clamp the vblank period to 0 if the refresh rate is larger than
120 hz for non-DC.  This allows us to remove the refresh rate
checks from powerplay for mclk switching.

Reviewed-by: Eric Huang <JinhuiEric.Huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:22 -05:00
Alex Deucher
a9b3c00165 drm/amd/powerplay/smu7: allow mclk switching with no displays
If there are no displays attached, there is no reason to disable
mclk switching.

Fixes mclks getting set to high when there are no displays attached.

Reviewed-by: Eric Huang <JinhuiEric.Huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2018-02-19 14:20:21 -05:00
Alex Deucher
d6bca7e714 drm/amd/powerplay/vega10: allow mclk switching with no displays
If there are no displays attached, there is no reason to disable
mclk switching.

Fixes mclks getting set to high when there are no displays attached.

Reviewed-by: Eric Huang <JinhuiEric.Huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2018-02-19 14:20:21 -05:00
Alex Deucher
6ce2d46c4f drm/amd/powerplay: use PP_CAP macro for disable_mclk_switching_for_frame_lock
Rather than open coding it.

Reviewed-by: Eric Huang <JinhuiEric.Huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:20 -05:00
Corentin Labbe
fc3703a0b6 drm/amd/powerplay: remove unused headers
All thoses headers are not used by any source files.
Lets just remove them.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:20 -05:00
Gustavo A. R. Silva
93bab704c1 drm/amdgpu_gem: fix error handling path in amdgpu_gem_va_update_vm
Currently, if amdgpu_vm_bo_update() fails, the returned error
is being ignored.

Fix this by properly checking _r_ after calling amdgpu_vm_bo_update.
Also, remove redundant code just before label _error_.

Addresses-Coverity-ID: 1464280 ("Unused value")
Fixes: 0abc6878fc ("drm/amdgpu: update VM PDs after the PTs")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:19 -05:00
Christian König
b3cd285fa6 drm/amdgpu: update the PASID mapping only on demand
Updating the PASID is rather heavyweight and shouldn't be done all the
time.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:18 -05:00
Christian König
c633c00bf0 drm/amdgpu: separate PASID mapping from VM flush v2
Stuffing the PASID mapping into the VM flush isn't flexible enough since
the PASID mapping changes not as often as we need a VM flush.

v2: add missing use of gmc_v7_0_emit_pasid_mapping

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:18 -05:00
Leo (Sunpeng) Li
ec47734a6d drm/amd/display: Fix increment when sampling OTF in DCE
Previously, the number of software segmets per region was reduced to 16.
This needs to be reflected in the sampling distance (increment) used when
translating to the hardware format.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:17 -05:00
Vitaly Prosyak
792474b736 drm/amd/display: De PQ implementation
Some refactoring and optimizations in color module.
Added de gamma 2.2 & 2.4, also re gamma 2.2.
Added interface for diagnostic for de gamma & de pq.

Signed-off-by: Vitaly Prosyak <vitaly.prosyak@amd.com>
Reviewed-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:17 -05:00
Harry Wentland
627c9a0a50 drm/amd/display: Remove unused dm_pp_ interfaces
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:16 -05:00
Eric Yang
fdf0c1c2f7 drm/amd/display: Add logging for aux DPCD access
Add basic logging for DPCD access. Does not print
by default.

Currently only prints first byte of the data accessed.

Technical debt: Need to make it so that the entire
data block accessed is printed. Also need to log
address space that's not DPCD.

Signed-off-by: Eric Yang <Eric.Yang2@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:15 -05:00
Tao
3b94a4007d drm/amd/display: Set vsc pack revision when DPCD revision is >= 1.2
Brightness couldn't change when booting up in DC mode.
It was because "psr_enabled" flag was not set to true before
setting vsc packet revision, causing packet rev setup was skipped.
Now instead of checking the psr flag, it checks if the DPCD_REV >= 1.2
and set the vsc packet revision.

Signed-off-by: Tao <xtao@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:15 -05:00
Anthony Koo
e923a355aa drm/amd/display: provide an interface to query firmware version
Signed-off-by: Anthony Koo <Anthony.Koo@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:14 -05:00
Harry Wentland
41b5b0a143 drm/amd/display: Add missing Vega defines to dal_asic_id
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Hersen Wu <hersenxs.wu@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:14 -05:00
Eric Yang
6531738842 drm/amd/display: Treat bad EDID as no EDID
We have an mst dock firmware that will emulate an EDID with bad
checksum.

v2: Tread -> Treat

Signed-off-by: Eric Yang <Eric.Yang2@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:13 -05:00
Ken Chalmers
05a2e8315f drm/amd/display: Remove duplicate entries from BIOS function table
Identical to the two entries above them.

Signed-off-by: Ken Chalmers <ken.chalmers@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:12 -05:00
Roman Li
3e332d3a5a drm/amd/display: Make FBC work without fbdev emulation
Previously, FBC dynamic allocation relied on connector modes
populated during dm init. This is only the case if
DRM_FBDEV_EMULATION config flag is enabled.
Moving fbc allocation from dm_late_init() to
amdgpu_dm_connector_get_modes() where actual modes init happens.

Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Shirish Shankarappa <Shirish.S@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:12 -05:00
John Barberiz
b0c4e97752 drm/amd/display: Remove delay on disconnect patch
HDMI HPD's generic solution makes the monitor
patch code unnecessary so anything related has
been removed.

Signed-off-by: John Barberiz <jbarberi@amd.com>
Reviewed-by: John Barberiz <jbarberi@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:11 -05:00
Leo (Sunpeng) Li
a0a31ec4ce drm/amd/display: Skip 2 frames when first reading CRC
Skipping the first frame will prevent uncoooked values most of the time.
However, in some unlikely cases, the second frame will be uncooked as
well.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:11 -05:00
Leo (Sunpeng) Li
ea41fb640d drm/amd/display: Expose DCE110 CRC functions for DCE8
Implement CRC for DCE8. Registers remain the same, so call DCE110 code
directly.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:10 -05:00
Leo (Sunpeng) Li
60c118c643 drm/amd/display: Rework DCE transform bit depth reduction programming.
Clear up the logic, and enable programming truncation as a bit reduction
mode.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:09 -05:00
Leo (Sunpeng) Li
aed7b06e49 drm/amd/display: When enabling CRC, disable dither & enable truncation
When user-mode is using 8bpc, the hardware represents it internally
using a higher bit depth. This causes problems when comparing CRCs for
color managment tests.

We need to disable dithering as well, since it makes CRC values
non-deterministic.

It's easy to see why dithering needs to be disabled, The reason why
truncation also needs to be enabled is better described with an example.
Consider the folowing which tests the color transform matrix (CTM):

Expected CRC = FB_A -> Degamma (Bypassed) -> CTM (Bypassed)
                                                  |
                                                  v
                            Obtain CRC  <- Regamma(Bypassed)

Actual CRC = FB_B -> Degamma (Bypassed) -> CTM (0.5*Identity)
                                                  |
                                                  v
                            Obtain CRC  <- Regamma(Bypassed)

FB_A contains a solid red color at half intensity (127 @ 8bpc)
FB_B contains a solid red color at full intensity (255 @ 8bpc)

We expect that Expected CRC = Actual CRC, but that's not the case. When
the CTM is applied, the output is at half intensity, but also at a
higher bit depth within hardware. i.e. 255/2 = 127.5: not representable
in 8bpc, but can be at 10bpc. This causes the two CRC's to be different.

The solution is to truncate the output bit depth to the same as input
when enabling CRC capture. Since Linux only supports 8bpc, hard code
that for now.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:09 -05:00
Leo (Sunpeng) Li
44af70a742 drm/amd/display: Expose dither setting functionality to Linux
We will need this to disable dither for CRC capture.

Signed-off-by: Leo (Sunpeng) Li <sunpeng.li@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-02-19 14:20:08 -05:00