During hibernation the cached DP port register value will be left with
whatever value we have there when we create the hibernation image.
Currently that means the port (and eDP PLL) will be off in the cached
value. However when we resume there is no guarantee that the value
in the actual register will match the cached value. If i915 isn't
loaded in the kernel that loads the hibernation image, the port may
well be on (eg. left on by the BIOS). The encoder state readout
does the right thing in this case and updates our encoder state
to reflect the actual hardware state. However the post-resume modeset
will then use the stale cached port register value in
intel_dp_link_down() and potentially confuse the hardware.
This was caught by the following assert
WARNING: CPU: 3 PID: 5288 at ../drivers/gpu/drm/i915/intel_dp.c:2184 assert_edp_pll+0x99/0xa0 [i915]
eDP PLL state assertion failure (expected on, current off)
on account of the eDP PLL getting prematurely turned off when
shutting down the port, since the DP_PLL_ENABLE bit wasn't set
in the cached register value.
Presumably I introduced this problem in
commit 6fec766283 ("drm/i915: Use intel_dp->DP in eDP PLL setup")
as before that we didn't update the cached value after shuttting the
port down. That's assuming the port got enabled at least once prior
to hibernating. If that didn't happen then the cached value would
still have been totally out of sync with reality (eg. first boot w/o
eDP on, then hibernate, and then resume with eDP on).
So, let's fix this properly and refresh the cached register value from
the hardware register during resume.
DDI platforms shouldn't use the cached value during port disable at
least, so shouldn't have this particular issue. They might still have
issues if we skip the initial modeset and then try to retrain the link
or something. But untangling this DP vs. DDI mess is a bigger topic,
so let's jut punt on DDI for now.
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: stable@vger.kernel.org
Fixes: 6fec766283 ("drm/i915: Use intel_dp->DP in eDP PLL setup")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1463162036-27931-1-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Imre Deak <imre.deak@intel.com>
(cherry picked from commit 64989ca4b2)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
A bit bigger than I would normally like, but most of the large changes are
for polaris support and since polaris went upstream in 4.7, I'd like
to get the fixes in so it's in good shape when the hw becomes available.
The major changes only touch the polaris code so there is little chance
for regressions on other asics. The rest are just the usual collection
of bug fixes.
* 'drm-fixes-4.7' of git://people.freedesktop.org/~agd5f/linux:
drm/amd/powerplay: enable clock stretch feature for polaris
drm/amdgpu/gfx8: update golden setting for polaris10
drm/amd/powerplay: enable avfs feature for polaris
drm/amdgpu/atombios: add avfs struct for Polaris10/11
drm/amd/powerplay: add avfs related define for polaris
drm/amd/powrplay: enable stutter_mode for polaris.
drm/amd/powerplay: disable UVD SMU handshake for MCLK.
drm/amd/powerplay: initialize variables which were missed.
drm/amd/powerplay: enable PowerContainment feature for polaris10/11.
drm/amd/powerplay: need to notify system bios pcie device ready
drm/amd/powerplay: fix bug that function parameter was incorect.
drm/amd/powerplay: fix logic error.
drm/amdgpu: initialize amdgpu_cgs_acpi_eval_object result value
drm/amdgpu: precedence bug in amdgpu_device_init()
drm/amdgpu: fix num_rbs exposed to userspace (v2)
drm/amdgpu: missing bounds check in amdgpu_set_pp_force_state()
Since HW trigger mode was suppoted we have faced with a issue
that Display panel didn't work correctly when trigger mode was changed
in booting time.
For this, we keep trigger mode with SW trigger mode in default mode
like we did before.
However, we will need to consider PSR(Panel Self Reflash) mode to resolve
this issue fundamentally later.
* 'exynos-drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos:
drm/exynos: use logical AND in exynos_drm_plane_check_size()
drm/exynos: remove superfluous inclusions of fbdev header
drm/exynos: g2d: drop the _REG postfix from the stride defines
drm/exynos: don't use HW trigger for Exynos5420/5422/5800
drm/exynos: fimd: don't set .has_hw_trigger in s3c6400 driver data
drm/exynos: dp: Fix NULL pointer dereference due uninitialized connector
Two bug fixes for the atmel-hlcdc driver.
* tag 'drm-atmel-hlcdc-fixes/for-4.7-rc5' of github.com:bbrezillon/linux-at91:
drm: atmel-hlcdc: Fix OF graph parsing
drm: atmel-hlcdc: actually disable scaling when no scaling is required
Hi Dave, just a couple of display fixes, both stable stuff. Maybe we'll
be able to enable fbc by default one day.
* tag 'drm-intel-fixes-2016-06-22' of git://anongit.freedesktop.org/drm-intel:
drm/i915/fbc: Disable on HSW by default for now
drm/i915: Revert DisplayPort fast link training feature
Imre Deak
Ville Syrjälä
Maarten Lankhorst
Dave Airlie
Dmitrii Tcvetkov
Lyude
Mika Kahola
Rex Zhu