The N value was computed by kernel driver that based on synchronous clock
mode. But only specific N value (0x8000) would be acceptable for
LG LP140WF6-SPM1 eDP panel which is running at asynchronous clock mode.
With the other N value, Tcon will enter BITS mode and display black screen.
Add this panel into quirk database and give particular N value when
calculate M/N divider.
v2: no update
v3: add lost commit messages back for version 2
v4: send patch to both intel-gfx and dri-devel
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Cooper Chiou <cooper.chiou@intel.com>
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Clint Taylor <clinton.a.taylor@intel.com>
Signed-off-by: Lee, Shawn C <shawn.c.lee@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1536733371-25004-4-git-send-email-shawn.c.lee@intel.com
Some DP dongles in particular seem to be fussy about too large
link M/N values. Set specific value for N divider can resolve
this issue per dongle vendor's comment. So configure N as
constant value (0x8000) to instead of reduce M/N formula when
specific DP dongle connected.
v2: add more comments for issue description and fix typo.
v3: add lost commit messages back for version 2
v4: send patch to both intel-gfx and dri-devel
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Cooper Chiou <cooper.chiou@intel.com>
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Clint Taylor <clinton.a.taylor@intel.com>
Tested-by: Clint Taylor <clinton.a.taylor@intel.com>
Signed-off-by: Lee, Shawn C <shawn.c.lee@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1536733371-25004-3-git-send-email-shawn.c.lee@intel.com
DP quirk list just compare sink or branch device's OUI so far.
That means particular vendor's products will be applied specific
change. This change would confirm device_id the same or not.
Then driver can implement some changes for branch/sink device
that really need additional WA.
v2: use sizeof instead of hard coded '6'
v3: add lost commit messages back for version 2
v4: send patch to both intel-gfx and dri-devel
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Cooper Chiou <cooper.chiou@intel.com>
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Clint Taylor <clinton.a.taylor@intel.com>
Tested-by: Clint Taylor <clinton.a.taylor@intel.com>
Signed-off-by: Lee, Shawn C <shawn.c.lee@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1536733371-25004-2-git-send-email-shawn.c.lee@intel.com
"(an unmatched left parenthesis
creates an unresolved tension
that will stay with you all day."
-- Randall Munroe
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180727203331.27778-1-paulo.r.zanoni@intel.com
This is something we've needed for a very long time now, as it makes
debugging issues with faulty MST hubs along with debugging issues
regarding us interfacing with hubs correctly vastly easier to debug.
Currently this can actually be done if you trace the i2c devices for DP
using ftrace but that's significantly less useful for a couple of
reasons:
- Tracing the i2c devices through ftrace means all of the traces are
going to contain a lot of "garbage" output that we're sending over the
i2c line. Most of this garbage comes from retrying transactions, DRM's
helper library adding extra transactions to work around bad hubs, etc.
- Having a user set up ftrace so that they can provide debugging
information is a lot more difficult then being able to say "just boot
with drm.debug=0x100"
- We can potentially expand upon this tracing in the future to print
debugging information in regards to other DP transactions like MST
sideband transactions
This is inspired by a patch Rob Clark sent to do this a long time back.
Neither of us could find the patch however, so we both assumed it would
probably just be easier to rewrite it anyway.
Cc: Rob Clark <robdclark@gmail.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180716154432.13433-1-lyude@redhat.com
This adds support for the DisplayPort CEC-Tunneling-over-AUX
feature that is part of the DisplayPort 1.3 standard.
Unfortunately, not all DisplayPort/USB-C to HDMI adapters with a
chip that has this capability actually hook up the CEC pin, so
even though a CEC device is created, it may not actually work.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180711132909.25409-2-hverkuil@xs4all.nl
-----BEGIN PGP SIGNATURE-----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=twst
-----END PGP SIGNATURE-----
Merge tag 'drm-next-2018-06-06-1' of git://anongit.freedesktop.org/drm/drm
Pull drm updates from Dave Airlie:
"This starts to support NVIDIA volta hardware with nouveau, and adds
amdgpu support for the GPU in the Kabylake-G (the intel + radeon
single package chip), along with some initial Intel icelake enabling.
Summary:
New Drivers:
- v3d - driver for broadcom V3D V3.x+ hardware
- xen-front - XEN PV display frontend
core:
- handle zpos normalization in the core
- stop looking at legacy pointers in atomic paths
- improved scheduler documentation
- improved aspect ratio validation
- aspect ratio support for 64:27 and 256:135
- drop unused control node code.
i915:
- Icelake (ICL) enabling
- GuC/HuC refactoring
- PSR/PSR2 enabling and fixes
- DPLL management refactoring
- DP MST fixes
- NV12 enabling
- HDCP improvements
- GEM/Execlist/reset improvements
- GVT improvements
- stolen memory first 4k fix
amdgpu:
- Vega 20 support
- VEGAM support (Kabylake-G)
- preOS scanout buffer reservation
- power management gfxoff support for raven
- SR-IOV fixes
- Vega10 power profiles and clock voltage control
- scatter/gather display support on CZ/ST
amdkfd:
- GFX9 dGPU support
- userptr memory mapping
nouveau:
- major refactoring for Volta GV100 support
tda998x:
- HDMI i2c CEC support
etnaviv:
- removed unused logging code
- license text cleanups
- MMU handling improvements
- timeout fence fix for 50 days uptime
tegra:
- IOMMU support in gr2d/gr3d drivers
- zpos support
vc4:
- syncobj support
- CTM, plane alpha and async cursor support
analogix_dp:
- HPD and aux chan fixes
sun4i:
- MIPI DSI support
tilcdc:
- clock divider fixes for OMAP-l138 LCDK board
rcar-du:
- R8A77965 support
- dma-buf fences fixes
- hardware indexed crtc/du group handling
- generic zplane property support
atmel-hclcdc:
- generic zplane property support
mediatek:
- use generic video mode function
exynos:
- S5PV210 FIMD variant support
- IPP v2 framework
- more HW overlays support"
* tag 'drm-next-2018-06-06-1' of git://anongit.freedesktop.org/drm/drm: (1286 commits)
drm/amdgpu: fix 32-bit build warning
drm/exynos: fimc: signedness bug in fimc_setup_clocks()
drm/exynos: scaler: fix static checker warning
drm/amdgpu: Use dev_info() to report amdkfd is not supported for this ASIC
drm/amd/display: Remove use of division operator for long longs
drm/amdgpu: Update GFX info structure to match what vega20 used
drm/amdgpu/pp: remove duplicate assignment
drm/sched: add rcu_barrier after entity fini
drm/amdgpu: move VM BOs on LRU again
drm/amdgpu: consistenly use VM moved flag
drm/amdgpu: kmap PDs/PTs in amdgpu_vm_update_directories
drm/amdgpu: further optimize amdgpu_vm_handle_moved
drm/amdgpu: cleanup amdgpu_vm_validate_pt_bos v2
drm/amdgpu: rework VM state machine lock handling v2
drm/amdgpu: Add runtime VCN PG support
drm/amdgpu: Enable VCN static PG by default on RV
drm/amdgpu: Add VCN static PG support on RV
drm/amdgpu: Enable VCN CG by default on RV
drm/amdgpu: Add static CG control for VCN on RV
drm/exynos: Fix default value for zpos plane property
...
Entry corresponding to 220 us setup time was missing. I am not aware of
any specific bug this fixes, but this could potentially result in enabling
PSR on a panel with a higher setup time requirement than supported by the
hardware.
I verified the value is present in eDP spec versions 1.3, 1.4 and 1.4a.
Fixes: 6608804b3d ("drm/dp: Add drm_dp_psr_setup_time()")
Cc: stable@vger.kernel.org
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jose Roberto de Souza <jose.souza@intel.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Tarun Vyas <tarun.vyas@intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180511195145.3829-3-dhinakaran.pandiyan@intel.com
DP_TRAINING_AUX_RD_INTERVAL with DP 1.3 spec changed bit scheeme from 8
bits to 7 in DPCD 0x000e. The 8th bit is used to identify extended
receiver capabilities. For panels that use this new feature wait interval
would be increased by 512 ms, when spec is max 16 ms. This behavior is
described in table 2-158 of DP 1.4 spec address 0000eh.
With the introduction of DP 1.4 spec main link clock recovery was
standardized to 100 us regardless of TRAINING_AUX_RD_INTERVAL value.
To avoid breaking panels that are not spec compiant we now warn on
invalid values.
V2: commit title/message, masking all 7 bits, warn on out of spec values.
V3: commit message, make link train clock recovery follow DP 1.4 spec.
V4: style changes
V5: typo
V6: print statement revisions, DP_REV to DPCD_REV, comment correction
V7: typo
V8: Style
V9: Strip out DPCD_REV_XX into seperate patch
v10: DPCD_REV_XX to DP_DPCD_REV_XX
Signed-off-by: Matt Atwood <matthew.s.atwood@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180504221800.17830-2-matthew.s.atwood@intel.com
The i2c adapter on DP AUX is purely a software construct. Linking
it to the device node of the parent device is wrong, as it leads to
2 devices sharing the same device node, which is bad practice, as
well as the i2c trying to populate children of the i2c adapter by
looking at the child device nodes of the parent device.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170113173630.22138-1-l.stach@pengutronix.de
Falling back to the lowest value is likely the only thing we can do, but
doing it silently seems like a bad thing to do. Catch it early and make
loud noises.
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171009092959.29021-1-jani.nikula@intel.com
Face the fact, there are Display Port sink and branch devices out there
in the wild that don't follow the Display Port specifications, or they
have bugs, or just otherwise require special treatment. Start a common
quirk database the drivers can query based on the DP device
identification. At least for now, we leave the workarounds for the
drivers to implement as they see fit.
For starters, add a branch device that can't handle full 24-bit main
link Mdiv and Ndiv main link attributes properly. Naturally, the
workaround of reducing main link attributes for all devices ended up in
regressions for other devices. So here we are.
v2: Rebase on DRM DP desc read helpers
v3: Fix the OUI memcmp blunder (Clint)
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Clint Taylor <clinton.a.taylor@intel.com>
Cc: Adam Jackson <ajax@redhat.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Tested-by: Clinton Taylor <clinton.a.taylor@intel.com>
Reviewed-by: Clinton Taylor <clinton.a.taylor@intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> # v2
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/91ec198dd95258dbf3bee2f6be739e0da73b4fdd.1495105635.git.jani.nikula@intel.com
Gabriel Krisman reported these warnings when building the documentation:
./drivers/gpu/drm/drm_dp_helper.c:1165: warning: No description found
for parameter 'crtc'
./drivers/gpu/drm/drm_dp_helper.c:1166: warning: No description found
for parameter 'crtc'
Reported-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170307203511.14258-1-tomeu.vizoso@collabora.com
Adds helpers for starting and stopping capture of frame CRCs through the
DPCD. When capture is on, a worker waits for vblanks and retrieves the
frame CRC to put it in the queue on the CRTC that is using the
eDP connector, so it's passed to userspace.
v2: Reuse drm_crtc_wait_one_vblank
Update locking, as drm_crtc_add_crc_entry now takes the lock
v3: Don't call wake_up_interruptible directly, that's now done in
drm_crtc_add_crc_entry.
v4: Style fixes (Sean Paul)
Reworked retry of CRC reads (Sean Paul)
Flush worker after stopping CRC generationa (Sean Paul)
v5: Move back to make the retry explicitly once
v6: Set and use the drm_crtc backpointer (Sean Paul)
Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170303133936.14964-3-tomeu.vizoso@collabora.com
I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).
Also some minor drive-by polish where it makes sense, I read a lot
of docs ...
v2: Comments from Gustavo.
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Rewiewed-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-2-daniel.vetter@ffwll.ch
Pull drm updates from Dave Airlie:
"Core:
- Fence destaging work
- DRIVER_LEGACY to split off legacy drm drivers
- drm_mm refactoring
- Splitting drm_crtc.c into chunks and documenting better
- Display info fixes
- rbtree support for prime buffer lookup
- Simple VGA DAC driver
Panel:
- Add Nexus 7 panel
- More simple panels
i915:
- Refactoring GEM naming
- Refactored vma/active tracking
- Lockless request lookups
- Better stolen memory support
- FBC fixes
- SKL watermark fixes
- VGPU improvements
- dma-buf fencing support
- Better DP dongle support
amdgpu:
- Powerplay for Iceland asics
- Improved GPU reset support
- UVD/VEC powergating support for CZ/ST
- Preinitialised VRAM buffer support
- Virtual display support
- Initial SI support
- GTT rework
- PCI shutdown callback support
- HPD IRQ storm fixes
amdkfd:
- bugfixes
tilcdc:
- Atomic modesetting support
mediatek:
- AAL + GAMMA engine support
- Hook up gamma LUT
- Temporal dithering support
imx:
- Pixel clock from devicetree
- drm bridge support for LVDS bridges
- active plane reconfiguration
- VDIC deinterlacer support
- Frame synchronisation unit support
- Color space conversion support
analogix:
- PSR support
- Better panel on/off support
rockchip:
- rk3399 vop/crtc support
- PSR support
vc4:
- Interlaced vblank timing
- 3D rendering CPU overhead reduction
- HDMI output fixes
tda998x:
- HDMI audio ASoC support
sunxi:
- Allwinner A33 support
- better TCON support
msm:
- DT binding cleanups
- Explicit fence-fd support
sti:
- remove sti415/416 support
etnaviv:
- MMUv2 refactoring
- GC3000 support
exynos:
- Refactoring HDMI DCC/PHY
- G2D pm regression fix
- Page fault issues with wait for vblank
There is no nouveau work in this tree, as Ben didn't get a pull
request in, and he was fighting moving to atomic and adding mst
support, so maybe best it waits for a cycle"
* tag 'drm-for-v4.9' of git://people.freedesktop.org/~airlied/linux: (1412 commits)
drm/crtc: constify drm_crtc_index parameter
drm/i915: Fix conflict resolution from backmerge of v4.8-rc8 to drm-next
drm/i915/guc: Unwind GuC workqueue reservation if request construction fails
drm/i915: Reset the breadcrumbs IRQ more carefully
drm/i915: Force relocations via cpu if we run out of idle aperture
drm/i915: Distinguish last emitted request from last submitted request
drm/i915: Allow DP to work w/o EDID
drm/i915: Move long hpd handling into the hotplug work
drm/i915/execlists: Reinitialise context image after GPU hang
drm/i915: Use correct index for backtracking HUNG semaphores
drm/i915: Unalias obj->phys_handle and obj->userptr
drm/i915: Just clear the mmiodebug before a register access
drm/i915/gen9: only add the planes actually affected by ddb changes
drm/i915: Allow PCH DPLL sharing regardless of DPLL_SDVO_HIGH_SPEED
drm/i915/bxt: Fix HDMI DPLL configuration
drm/i915/gen9: fix the watermark res_blocks value
drm/i915/gen9: fix plane_blocks_per_line on watermarks calculations
drm/i915/gen9: minimum scanlines for Y tile is not always 4
drm/i915/gen9: fix the WaWmMemoryReadLatency implementation
drm/i915/kbl: KBL also needs to run the SAGV code
...
- more core cleanup patches to prep drm_file to be used for
kernel-internal contexts (David Herrmann)
- more split-up+docs for drm_crtc.c
- lots of small fixes and polish all over
* tag 'topic/drm-misc-2016-09-25' of git://anongit.freedesktop.org/drm-intel: (37 commits)
drm: bridge: analogix/dp: mark symbols static where possible
drm/bochs: mark bochs_connector_get_modes() static
drm/bridge: analogix_dp: Improve panel on time
drm/bridge: analogix_dp: Don't read EDID if panel present
drm/bridge: analogix_dp: Remove duplicated code
Revert "drm/i2c: tda998x: don't register the connector"
drm: Fix plane type uabi breakage
dma-buf/sync_file: free fences array in num_fences is 1
drm/i2c: tda998x: don't register the connector
drm: Don't swallow error codes in drm_dev_alloc()
drm: Distinguish no name from ENOMEM in set_unique()
drm: Remove dirty property from docs
drm/doc: Document color space handling
drm: Extract drm_color_mgmt.[hc]
drm/doc: Polish plane composition property docs
drm: Conslidate blending properties in drm_blend.[hc]
drm/doc: Polish for drm_plane.[hc]
drm: Extract drm_plane.[hc]
drm/tilcdc: Add atomic and crtc headers to crtc.c
drm: Fix typo in encoder docs
...
- refactor the sseu code (Imre)
- refine guc dmesg output (Dave Gordon)
- more vgpu work
- more skl wm fixes (Lyude)
- refactor dpll code in prep for upfront link training (Jim Bride et al)
- consolidate all platform feature checks into intel_device_info (Carlos Santa)
- refactor elsp/execlist submission as prep for re-submission after hang
recovery and eventually scheduling (Chris Wilson)
- allow synchronous gpu reset handling, to remove tricky/impossible/fragile
error recovery code (Chris Wilson)
- prep work for nonblocking (execlist) submission, using fences to track
depencies and drive elsp submission (Chris Wilson)
- partial error recover/resubmission of non-guilty batches after hangs (Chris Wilson)
- full dma-buf implicit fencing support (Chris Wilson)
- dp link training fixes (Jim, Dhinkaran, Navare, ...)
- obey dp branch device pixel rate/bpc/clock limits (Mika Kahola), needed for
many vga dongles
- bunch of small cleanups and polish all over, as usual
[airlied: printing macros collided]
* tag 'drm-intel-next-2016-09-19' of git://anongit.freedesktop.org/drm-intel: (163 commits)
drm/i915: Update DRIVER_DATE to 20160919
drm: Fix DisplayPort branch device ID kernel-doc
drm/i915: use NULL for NULL pointers
drm/i915: do not use 'false' as a NULL pointer
drm/i915: make intel_dp_compute_bpp static
drm: Add DP branch device info on debugfs
drm/i915: Update bits per component for display info
drm/i915: Check pixel rate for DP to VGA dongle
drm/i915: Read DP branch device SW revision
drm/i915: Read DP branch device HW revision
drm/i915: Cleanup DisplayPort AUX channel initialization
drm: Read DP branch device id
drm: Helper to read max bits per component
drm: Helper to read max clock rate
drm: Drop VGA from bpc definitions
drm: Add missing DP downstream port types
drm/i915: Add ddb size field to device info structure
drm/i915/guc: general tidying up (submission)
drm/i915/guc: general tidying up (loader)
drm/i915: clarify PMINTRMSK/pm_intr_keep usage
...
Read DisplayPort branch device info from through debugfs
interface.
v2: use drm_dp_helper routines to collect data
v3: cleanup to match the drm_dp_helper.c patches introduced
earlier in this series
v4: move DP branch device info to function 'intel_dp_branch_device_info()'
v5: initial step to move debugging info from intel_dp. to drm_dp_helper.c (Daniel)
v6: read hw and sw revision without using specific drm_dp_helper routines
v7: indentation fixes (Jim Bride)
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1473419458-17080-12-git-send-email-mika.kahola@intel.com
Helper routine to read out maximum supported bits per
component for DisplayPort legay converters.
v2: Return early if detailed port cap info is not available.
Replace if-else ladder with switch-case (Ville)
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1473419458-17080-5-git-send-email-mika.kahola@intel.com
Helper routine to read out maximum supported pixel rate
for DisplayPort legay VGA converter or TMDS clock rate
for other digital legacy converters. The helper returns
clock rate in kHz.
v2: Return early if detailed port cap info is not available.
Replace if-else ladder with switch-case (Ville)
Reviewed-by: Jim Bride <jim.bride@linux.intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1473419458-17080-4-git-send-email-mika.kahola@intel.com
This makes it trivial to constify them, so do that.
Signed-off-by: Peter Rosin <peda@axentia.se>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
They're only used internally within the dp helpers. Also nuke the
kerneldoc (we only document the driver interface in the drm shared
functions). And move the header file from the public include/
directory to the source files into drm_crtc_helper_internal.h, similar
to how we already have drm_crtc_internal.h.
While at it also move drm_fb_helper_modinit since that belongs in
there, too.
I noticed this all since I spotted kerneldoc which wasn't pulled into
the rst templates.
v2: Update Copyright date.
Cc: Sean Paul <seanpaul@chromium.org>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471034937-651-16-git-send-email-daniel.vetter@ffwll.ch
Timeouts can be errors, but timeouts are also usually normal behavior
and happen a lot. Since the kernel already lets us know when we're
suppressing messages due to rate limiting, rate limit timeout errors so
we don't make too much noise in the kernel log.
Signed-off-by: Lyude <cpaul@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470443443-27252-8-git-send-email-cpaul@redhat.com
Since we always retry in drm_dp_dpcd_access() regardless of the error,
we're going to make a lot of noise if the aux->transfer function prints
it's own errors (as is the case with radeon). If we can print the error
code here, this reduces the need for drivers to do this. So instead of
having to print "dp_aux_ch timed out" over 32 times we can just print
once.
Signed-off-by: Lyude <cpaul@redhat.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470443443-27252-2-git-send-email-cpaul@redhat.com
Add a small helper to parse the PSR setup time from the DPCD PSR
capabilities and return the value in microseconds.
v2: Don't waste so many bytes on the psr_setup_time_us[] table
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Restore the correct behaviour (as in check msg.reply) when aux
->transfer() returns 0. It got removed in
commit 82922da391 ("drm/dp_helper: Retry aux transactions on all errors")
Now I can actually dump the "entire" DPCD on a Dell UP2314Q with
ddrescue. It has some offsets in the DPCD that can't be read
for some resaon, all you get is defers. Previously ddrescue would
just give up at the first unredable offset on account of
read() returning 0 means EOF. Here's the ddrescue log
for the interested:
0x00000000 0x00001400 +
0x00001400 0x00000030 -
0x00001430 0x000001D0 +
0x00001600 0x00000030 -
0x00001630 0x0001F9D0 +
0x00021000 0x00000001 -
0x00021001 0x000DEFFF +
Cc: Lyude <cpaul@redhat.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch
Cc: stable@vger.kernel.org
Fixes: 82922da391 ("drm/dp_helper: Retry aux transactions on all errors")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
When trying to split up the initialisation phase and the registration
phase, one immediate problem encountered is trying to use our own i2c
devices before registration with userspace (to read EDID during device
discovery). drm_dp_aux in particular only offers an interface for setting
up the device *after* we have exposed the connector via sysfs. In order
to break the chicken-and-egg problem, export drm_dp_aux_init() to
minimally prepare the i2c device for internal use before
drm_connector_register().
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: dri-devel@lists.freedesktop.org
[danvet: Amend kerneldoc slightly.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1466152398-20157-3-git-send-email-chris@chris-wilson.co.uk
Rather than have both drm_dp_aux lock within its transfer, and i2c to
lock around the transfer, use the same lock by filling in the locking
callbacks that i2c wants to use. We require our own hw_mutex as we
bypass i2c_transfer for drm_dp_dpcd_access().
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Rafael Antognolli <rafael.antognolli@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1466152398-20157-2-git-send-email-chris@chris-wilson.co.uk
This is part of a patch series to migrate all of the workarounds for
commonly seen behavior from bad sinks in intel_dp_dpcd_read_wake() to drm's
DP helper.
Some sinks will just return garbage for the first aux tranaction they
receive when coming out of sleep mode, so we need to perform an additional
read before the actual read to workaround this.
Changes since v5
- If the throwaway read in drm_dp_dpcd_read() fails, return the error
from that instead of continuing. This follows the same logic we do in
drm_dp_dpcd_access() (e.g. the error from the first transaction may
differ from the errors that proceeding attempts might return).
Signed-off-by: Lyude <cpaul@redhat.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1460730335-5012-1-git-send-email-cpaul@redhat.com
This is part of a patch series to migrate all of the workarounds for
commonly seen behavior from bad sinks in intel_dp_dpcd_read_wake() to
drm's DP helper.
We cannot rely on sinks NACKing or deferring when they can't receive
transactions, nor can we rely on any other sort of consistent error to
know when we should stop retrying. As such, we need to just retry
unconditionally on errors. We also make sure here to return the error we
encountered during the first transaction, since it's possible that
retrying the transaction might return a different error then we had
originally.
This, along with the previous patch, work around a weird bug with the
ThinkPad T560's and it's dock. When resuming the laptop, it appears that
there's a short period of time where we're unable to complete any aux
transactions, as they all immediately timeout. The only machine I'm able
to reproduce this on is the T560 as other production Skylake models seem
to be fine. The period during which AUX transactions fail appears to be
around 22ms long. AFAIK, the dock for the T560 never actually turns off,
the only difference is that it's in SST mode at the start of the resume
process, so it's unclear as to why it would need so much time to come
back up.
There's been a discussion on this issue going on for a while on the
intel-gfx mailing list about this that has, in addition to including
developers from Intel, also had the correspondence of one of the
hardware engineers for Intel:
http://www.spinics.net/lists/intel-gfx/msg88831.htmlhttp://www.spinics.net/lists/intel-gfx/msg88410.html
We've already looked into a couple of possible explanations for the
problem:
- Calling intel_dp_mst_resume() before right fix.
intel_runtime_pm_enable_interrupts(). This was the first fix I tried,
and while it worked it definitely wasn't the right fix. This worked
because DP aux transactions don't actually require interrupts to work:
static uint32_t
intel_dp_aux_wait_done(struct intel_dp *intel_dp, bool has_aux_irq)
{
struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
struct drm_device *dev = intel_dig_port->base.base.dev;
struct drm_i915_private *dev_priv = dev->dev_private;
i915_reg_t ch_ctl = intel_dp->aux_ch_ctl_reg;
uint32_t status;
bool done;
#define C (((status = I915_READ_NOTRACE(ch_ctl)) & DP_AUX_CH_CTL_SEND_BUSY) == 0)
if (has_aux_irq)
done = wait_event_timeout(dev_priv->gmbus_wait_queue, C,
msecs_to_jiffies_timeout(10));
else
done = wait_for_atomic(C, 10) == 0;
if (!done)
DRM_ERROR("dp aux hw did not signal timeout (has irq: %i)!\n",
has_aux_irq);
#undef C
return status;
}
When there's no interrupts enabled, we end up timing out on the
wait_event_timeout() call, which causes us to check the DP status
register once to see if the transaction was successful or not. Since
this adds a 10ms delay to each aux transaction, it ends up adding a
long enough delay to the resume process for aux transactions to become
functional again. This gave us the illusion that enabling interrupts
had something to do with making things work again, and put me on the
wrong track for a while.
- Interrupts occurring when we try to perform the aux transactions
required to put the dock back into MST mode. This isn't the problem,
as the only interrupts I've observed that come during this timeout
period are from the snd_hda_intel driver, and disabling that driver
doesn't appear to change the behavior at all.
- Skylake's PSR block causing issues by performing aux transactions
while we try to bring the dock out of MST mode. Disabling PSR through
i915's command line options doesn't seem to change the behavior
either, nor does preventing the DMC firmware from being loaded.
Since this investigation went on for about 2 weeks, we decided it would
be better for the time being to just workaround this issue by making
sure AUX transactions wait a short period of time before retrying.
Signed-off-by: Lyude <cpaul@redhat.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1460559513-32280-3-git-send-email-cpaul@redhat.com
This is part of a patch series to migrate all of the workarounds for
commonly seen behavior from bad sinks in intel_dp_dpcd_read_wake() to
drm's DP helper.
Some sinks need some time during the process of resuming the system from
sleep before they're ready to handle transactions. While it would be
nice if they responded with NACKs in these scenarios, this isn't always
the case as a few sinks will just timeout on all of the transactions
they receive until they're ready.
Signed-off-by: Lyude <cpaul@redhat.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1460559513-32280-2-git-send-email-cpaul@redhat.com
1) don't let other threads trying to bang on aux channel interrupt the
defer timeout/logic
2) don't let other threads interrupt the i2c over aux logic
Technically, according to people who actually have the DP spec, this
should not be required. In practice, it makes some troublesome Dell
monitor (and perhaps others) work, so probably a case of "It's compliant
if it works with windows" on the hw vendor's part..
v2: rebased to come before DPCD/AUX logging patch for easier backport
to stable branches.
Reported-by: Dave Wysochanski <dwysocha@redhat.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1274157
Cc: stable@vger.kernel.org
Signed-off-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This module is heavily based on i2c-dev. Once loaded, it provides one
dev node per DP AUX channel, named drm_dp_auxN, where N is an integer.
It's possible to know which connector owns this aux channel by looking
at the respective sysfs /sys/class/drm_aux_dev/drm_dp_auxN/connector, if
the connector device pointer was correctly set in the aux helper struct.
Two main operations are provided on the registers read and write. The
address of the register to be read or written is given using lseek. The
seek position is updated upon read or write.
v2:
- lseek is used to select the register to read/write
- read/write are used instead of ioctl
- no blocking_notifier is used, just a direct callback
v3:
- use drm_dp_aux_dev prefix for public functions
- chardev is named drm_dp_auxN
- read/write don't allocate a buffer anymore, and transfer up to 16 bytes a
time
- remove notifier list from the implementation
- option on menuconfig is now a boolean
- add inline stub functions to avoid breakage when this option is disabled
v4:
- fix build system changes - actually disable this module when not selected.
v5:
- Use kref to avoid device closing while still in use
- Don't use list, use an idr for storing aux_dev
- Remove "connector" attribute
- set aux.dev to the connector drm_connector device, instead of
drm_device
v6:
- Use atomic_t for usage count
- Use a mutex instead of spinlock for idr lock
- Destroy chardev immediately on unregister
- other minor suggestions from Ville
v7:
- style fixes
- error handling fixes
v8:
- more error handling fixes
v9:
- remove module_init and module_exit, and add drm_dp_aux_dev_init/exit
to drm_kms_helper_init/exit.
Signed-off-by: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1453417821-2811-3-git-send-email-rafael.antognolli@intel.com
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
iQEcBAABAgAGBQJV/yX5AAoJEHm+PkMAQRiGUc4IAIFtSt2EORex45d2c64Varjm
4wVJM6k1xz0e8c5bI5D03y/WaefIC2LlKHtWw4+TytnwWEryuGQ1IitvDPZLIntk
I2tUN1IzyxZrJcG2GyfozjxSxeIcaL7us5j7555kEaRVWMamqDaQgVgEKFRqD43N
M4y8qRUeU3OiaL3OhQ9beSfpI/XqjaT+ECGO5HKC3NOJtTrD+cFqLAG9ScCPhvtk
YrrXx3K6J3mylvdvJ5W6JlxOrhFMO+YzViy2bRY8OnAR2vD88p61eT8V2+ENbnMj
+AqXS4HOBpJ6I1Qhff99r0YyvVT/ln9dW7qLAXK3WG27z6HOSWr8KWNUyQD2VLE=
=9yBb
-----END PGP SIGNATURE-----
Merge tag 'v4.3-rc2' into topic/drm-misc
Backmerge Linux 4.3-rc2 because of conflicts in the dp helper code
between bugfixes and new code. Just adjacent lines really.
On top of that there's a silent conflict in the new fsl-dcu driver
merged into 4.3 and
commit 844f9111f6
Author: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Date: Wed Sep 2 10:42:40 2015 +0200
drm/atomic: Make prepare_fb/cleanup_fb only take state, v3.
which Thierry Reding spotted and provided a fixup for.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
When an i2c WRITE gets an i2c defer or short i2c ack reply, we are
supposed to switch the request from I2C_WRITE to I2C_WRITE_STATUS_UPDATE
when we continue to poll for the completion of the request.
v2: Don't assume DP_AUX_I2C_WRITE is 0 even though it is, to make the
code more obvious to the casual reader (Jani)
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
[danvet: Resolve conflict due to changed context.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
To help with debugging i2c-over-aux issues, add a module parameter than
can be used to tweak the assumed i2c bus speed, and thus the maximum
number of retries we will do for each aux message.
Cc: Simon Farnsworth <simon.farnsworth@onelan.com>
Cc: moosotc@gmail.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Simon Farnsworth <simon.farnsworth@onelan.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Calculate the number of retries we should do for each i2c-over-aux
message based on the time it takes to perform the i2c transfer vs. the
aux transfer. We assume the shortest possible length for the aux
transfer, and the longest possible (exluding clock stretching) for the
i2c transfer.
The DP spec has some examples on how to calculate this, but we don't
calculate things quite the same way. The spec doesn't account for the
retry interval (assumes immediate retry on defer), and doesn't assume
the best/worst case behaviour as we do.
Note that currently we assume 10 kHz speed for the i2c bus. Some real
world devices (eg. some Apple DP->VGA dongle) fails with less than 16
retries. and that would correspond to something close to 15 kHz (with
our method of calculating things) But let's just go for 10 kHz to be
on the safe side. Ideally we should query/set the i2c bus speed via
DPCD but for now this should at leaast remove the regression from the
1->16 byte trasnfer size change. And of course if the sink completes
the transfer quicker this shouldn't slow things down since we don't
change the interval between retries.
I did a few experiments with a DP->DVI dongle I have that allows you
to change the i2c bus speed. Here are the results of me changing the
actual bus speed and the assumed bus speed and seeing when we start
to fail the operation:
actual i2c khz assumed i2c khz max retries
1 1 ok -> 2 fail 211 ok -> 106 fail
5 8 ok -> 9 fail 27 ok -> 24 fail
10 17 ok -> 18 fail 13 ok -> 12 fail
100 210 ok -> 211 fail 2 ok -> 1 fail
So based on that we have a fairly decent safety margin baked into
the formula to calculate the max number of retries.
Fixes a regression with some DP dongles from:
commit 1d002fa720
Author: Simon Farnsworth <simon.farnsworth@onelan.co.uk>
Date: Tue Feb 10 18:38:08 2015 +0000
drm/dp: Use large transactions for I2C over AUX
v2: Use best case for AUX and worst case for i2c (Simon Farnsworth)
Add a define our AUX retry interval and account for it
v3: Make everything usecs to avoid confusion about units (Daniel)
Add a comment reminding people about the AUX bitrate (Daniel)
Use DIV_ROUND_UP() since we're after the "worst" case for i2c
Cc: Simon Farnsworth <simon.farnsworth@onelan.com>
Cc: moosotc@gmail.com
Tested-by: moosotc@gmail.com
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91451
Reviewed-by: Simon Farnsworth <simon.farnsworth@onelan.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Currently we react to native and i2c defers by waiting either 400-500 us
or 500-600 us, depending on which code path we take. Consolidate them
all to one define AUX_RETRY_INTERVAL which defines the minimum interval.
Since we've been using two different intervals pick the longer of them
and define AUX_RETRY_INTERVAL as 500 us. For the maximum just use
AUX_RETRY_INTERVAL+100 us.
I want to have a define for this so that I can use it when calculating
the estimated duration of i2c-over-aux transfers. Without a define it
would be very easy to change the sleep duration and neglect to update
the i2c-over-aux estimates.
Cc: Simon Farnsworth <simon.farnsworth@onelan.com>
Cc: moosotc@gmail.com
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Simon Farnsworth <simon.farnsworth@onelan.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
For test 4.2.2.5 to pass per the Link CTS Core 1.2 rev1.1 spec, the source
device must attempt at least 7 times to read the EDID when it receives an
I2C defer. The normal DRM code makes only 7 retries, regardless of whether
or not the response is a native defer or an I2C defer. Test 4.2.2.5 fails
since there are native defers interspersed with the I2C defers which
results in less than 7 EDID read attempts.
The solution is to add the numer of defers to the retry counter when an I2C
DEFER is returned such that another read attempt will be made. This situation
should normally only occur in compliance testing, however, as a worse case
real-world scenario, it would result in 13 attempts ( 6 native defers, 7 I2C
defers) for a single transaction to complete. The net result is a slightly
slower response to an EDID read that shouldn't significantly impact overall
performance.
V2:
- Added a check on the number of I2C Defers to limit the number
of times that the retries variable will be decremented. This
is to address review feedback regarding possible infinite loops
from misbehaving sink devices.
V3:
- Fixed the limit value to 7 instead of 8 to get the correct retry
count.
- Combined the increment of the defer count into the if-statement
V4:
- Removed i915 tag from subject as the patch is not i915-specific
V5:
- Updated the for-loop to add the number of i2c defers to the retry
counter such that the correct number of retry attempts will be
made
Signed-off-by: Todd Previte <tprevite@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The debug message is missing a newline at the end and it makes the
logs hard to read when a device defers a lot. Simple 2-character fix
adds the newline at the end.
Signed-off-by: Todd Previte <tprevite@gmail.com>
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
When doing a native or i2c aux write the sink will indicate the number
of bytes written even if it the nacks the transfer. When we receive a
nack we just return an error upwards, but it might still be interesting
to see how many bytes made it before the nack. So include that information
in the debug messages.
v2: Also print the message size (Jani)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Older DisplayPort to DVI-D Dual Link adapters designed by Bizlink have bugs
in their I2C over AUX implementation (fixed in newer revisions). They work
fine with Windows, but fail with Linux.
It turns out that they cannot keep an I2C transaction open unless the
previous read was 16 bytes; shorter reads can only be followed by a zero
byte transfer ending the I2C transaction.
Copy Windows's behaviour, and read 16 bytes at a time. If we get a short
reply, assume that there's a hardware bottleneck, and shrink our read size
to match. For this purpose, use the algorithm in the DisplayPort 1.2 spec,
in the hopes that it'll be closest to what Windows does.
Also provide an unsafe module parameter for testing smaller transfer sizes,
in case there are sinks out there that cannot work with Windows.
Note also that despite the previous comment in drm_dp_i2c_xfer, this speeds
up native DP EDID reads; Ville Syrjälä <ville.syrjala@linux.intel.com> found
the following changes in his testing:
Device under test: old -> with this patch
DP->DVI (OUI 001cf8): 40ms -> 35ms
DP->VGA (OUI 0022b9): 45ms -> 38ms
Zotac DP->2xHDMI: 25ms -> 4ms
Asus PB278 monitor: 22ms -> 3ms
A back of the envelope calculation shows that peak theoretical transfer rate
for 1 byte reads is around 60 kbit/s; with 16 byte reads, this increases to
around 500 kbit/s, which explains the increase in speed.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=55228
Tested-by: Aidan Marks <aidanamarks@gmail.com> (v3)
Signed-off-by: Simon Farnsworth <simon.farnsworth@onelan.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
