Highlights:
- follow-up refactoring after the shared dpll rework that landed in 3.11
- oddball prep cleanups from Ben for ppgtt
- encoder->get_config state tracking infrastructure from Jesse
- used by the experimental fastboot support from Jesse (disabled by
default)
- make the error state file official and add it to our sysfs interface
(Mika)
- drm_mm prep changes from Ben, prepares to embedd the drm_mm_node (which
will be used by the vma rework later on)
- interrupt handling rework, follow up cleanups to the VECS enabling, hpd
storm handling and fifo underrun reporting.
- Big pile of smaller cleanups, code improvements and related stuff.
* tag 'drm-intel-next-2013-07-12' of git://people.freedesktop.org/~danvet/drm-intel: (72 commits)
drm/i915: clear DPLL reg when disabling i9xx dplls
drm/i915: Fix up cpt pixel multiplier enable sequence
drm/i915: clean up vlv ->pre_pll_enable and pll enable sequence
drm/i915: move error state to own compilation unit
drm/i915: Don't attempt to read an unitialized stack value
drm/i915: Use for_each_pipe() when possible
drm/i915: don't enable PM_VEBOX_CS_ERROR_INTERRUPT
drm/i915: unify ring irq refcounts (again)
drm/i915: kill dev_priv->rps.lock
drm/i915: queue work outside spinlock in hsw_pm_irq_handler
drm/i915: streamline hsw_pm_irq_handler
drm/i915: irq handlers don't need interrupt-safe spinlocks
drm/i915: kill lpt pch transcoder->crtc mapping code for fifo underruns
drm/i915: improve GEN7_ERR_INT clearing for fifo underrun reporting
drm/i915: improve SERR_INT clearing for fifo underrun reporting
drm/i915: extract ibx_display_interrupt_update
drm/i915: remove unused members from drm_i915_private
drm/i915: don't frob mm.suspended when not using ums
drm/i915: Fix VLV DP RBR/HDMI/DAC PLL LPF coefficients
drm/i915: WARN if the bios reserved range is bigger than stolen size
...
Conflicts:
drivers/gpu/drm/i915/i915_gem.c
more DPM fixes for radeon.
* 'drm-fixes-3.11' of git://people.freedesktop.org/~agd5f/linux:
drm/radeon/dpm: add debugfs support for RS780/RS880 (v3)
drm/radeon/dpm/atom: fix broken gcc harder
drm/radeon/dpm/atom: restructure logic to work around a compiler bug
drm/radeon/dpm: fix atom vram table parsing
drm/radeon: fix an endian bug in atom table parsing
drm/radeon: add a module parameter to disable aspm
This allows you to look at the current DPM state via
debugfs.
Due to the way the hardware works on these asics, there's
no way to look up exactly what power state we are in, so
we make the best guess we can based on the current sclk.
v2: Anthoine's version
v3: fix ref div
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
The GEM CMA PRIME import/export helpers have been removed in favor of
generic GEM PRIME helpers with GEM CMA low-level operations. Fix the
driver accordingly.
Reported-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Mark Brown <broonie@linaro.org>
The GEM CMA PRIME import/export helpers have been removed in favor of
generic GEM PRIME helpers with GEM CMA low-level operations. Fix the
driver accordingly.
Reported-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Mark Brown <broonie@linaro.org>
One feature latecomer, I've forgotten to merge the patch to reeanble the
Haswell power well feature now that the audio interaction is fixed up.
Since that was the only unfixed issue with it I've figured I could throw
it in a bit late, and it's trivial to revert in case I'm wrong.
Otherwise all bug/regression fixes:
- Fix status page reinit after gpu hangs, spotted by more paranoid igt
checks.
- Fix object list walking fumble regression in the shrinker (only the
counting part, the actual shrinking code was correct so no Oops
potential), from Xiong Zhang.
- Fix DP 1.2 bw limits (Imre).
- Restore legacy forcewake on ivb, too many broken biosen out there. We
dump a warn though that recent userspace might fall over with that
config (Guenter Roeck).
- Patch up the gen2 cs tlb w/a.
- Improve the fence coherency w/a now that we have a better understanding
what's going on. The removed wbinvd+ipi should make -rt folks happy. Big
thanks to Jon Bloomfield for figuring this out, patches from Chris.
- Fix write-read race when switching ring (Chris). Spotted with code
inspection, but now we also have an igt for it.
There's an ugly regression we're still working on introduced between
3.10-rc7 and 3.10.0. Unfortunately we can't just revert the offender since
that one fixes another regression :( I've asked Steven to include my
-fixes branch into linux-next to prevent such fallout in the future,
hopefully.
* tag 'drm-intel-fixes-2013-07-11' of git://people.freedesktop.org/~danvet/drm-intel:
Revert "drm/i915: Workaround incoherence between fences and LLC across multiple CPUs"
drm/i915: Fix incoherence with fence updates on Sandybridge+
drm/i915: Fix write-read race with multiple rings
Partially revert "drm/i915: unconditionally use mt forcewake on hsw/ivb"
drm/i915: fix lane bandwidth capping for DP 1.2 sinks
drm/i915: fix up ring cleanup for the i830/i845 CS tlb w/a
drm/i915: Correct obj->mm_list link to dev_priv->dev_priv->mm.inactive_list
drm/i915: switch disable_power_well default value to 1
drm/i915: reinit status page registers after gpu reset
More DPM fixes, r6xx DMA fix for bo moving, UVD fixes,
one major regression fix on bootup on some machine (ttm backoff missing)
* 'drm-fixes-3.11' of git://people.freedesktop.org/~agd5f/linux:
radeon kms: do not flush uninitialized hotplug work
drm/radeon/dpm/sumo: handle boost states properly when forcing a perf level
drm/radeon: align VM PTBs (Page Table Blocks) to 32K
drm/radeon: allow selection of alignment in the sub-allocator
drm/radeon: never unpin UVD bo v3
drm/radeon: fix UVD fence emit
drm/radeon: add fault decode function for CIK
drm/radeon: add fault decode function for SI (v2)
drm/radeon: add fault decode function for cayman/TN (v2)
drm/radeon: use radeon device for request firmware
drm/radeon: add missing ttm_eu_backoff_reservation to radeon_bo_list_validate
drm/radeon: use CP DMA on r6xx for bo moves
drm/radeon: implement bo copy callback using CP DMA (v2)
drm/radeon: Disable dma rings for bo moves on r6xx
drm/radeon/dpm: disable gfx PG on PALM
drm/radeon/hdmi: make sure we have an afmt block assigned
Need to properly enable/disable boost states when forcing a performance
level.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Covers requirements of all current asics.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
There are cases where we need more than 4k alignment. No
functional change with this commit.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Changing the UVD BOs offset on suspend/resume doesn't work because the VCPU
internally keeps pointers to it. Just keep it always pinned and save the
content manually.
Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=66425
v2: fix compiler warning
v3: fix CIK support
Note: a version of this patch needs to go to stable.
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Currently doesn't matter cause we allocate the fence in the
lower 265MB anyway.
Reported-by: Frank Huang <FrankR.Huang@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Helpful for debugging GPUVM errors as we can see what
hw block and page generated the fault in the log.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Helpful for debugging GPUVM errors as we can see what
hw block and page generated the fault in the log.
v2: simplify fault decoding
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Helpful for debugging GPUVM errors as we can see what
hw block and page generated the fault in the log.
v2: simplify fault decoding
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Avoid creating temporary platform device that will lead to issue
when several radeon gpu are in same computer. Instead directly use
the radeon device for requesting firmware.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Op 10-07-13 12:03, Markus Trippelsdorf schreef:
> On 2013.07.10 at 11:56 +0200, Maarten Lankhorst wrote:
>> Op 10-07-13 11:46, Markus Trippelsdorf schreef:
>>> On 2013.07.10 at 11:29 +0200, Maarten Lankhorst wrote:
>>>> Op 10-07-13 11:22, Markus Trippelsdorf schreef:
>>>>> By simply copy/pasting a big document under LibreOffice my system hangs
>>>>> itself up. Only a hard reset gets it working again.
>>>>> see also: https://bugs.freedesktop.org/show_bug.cgi?id=66551
>>>>>
>>>>> I've bisected the issue to:
>>>>>
>>>>> commit ecff665f5e
>>>>> Author: Maarten Lankhorst <m.b.lankhorst@gmail.com>
>>>>> Date: Thu Jun 27 13:48:17 2013 +0200
>>>>>
>>>>> drm/ttm: make ttm reservation calls behave like reservation calls
>>>>>
>>>>> This commit converts the source of the val_seq counter to
>>>>> the ww_mutex api. The reservation objects are converted later,
>>>>> because there is still a lockdep splat in nouveau that has to
>>>>> resolved first.
>>>>>
>>>>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
>>>>> Reviewed-by: Jerome Glisse <jglisse@redhat.com>
>>>>> Signed-off-by: Dave Airlie <airlied@redhat.com>
>>>> Hey,
>>>>
>>>> Can you try current head with CONFIG_PROVE_LOCKING set and post the
>>>> lockdep splat from dmesg, if any? If there is any locking issue
>>>> lockdep should warn about it. Lockdep will turn itself off after the
>>>> first splat, so if the lockdep splat happens before running the
>>>> affected parts those will have to be fixed first.
>>> There was an unrelated EDAC lockdep splat, so I simply disabled it.
>>>
>>> This is what I get:
>>>
>>> Jul 10 11:40:44 x4 kernel: ================================================
>>> Jul 10 11:40:44 x4 kernel: [ BUG: lock held when returning to user space! ]
>>> Jul 10 11:40:44 x4 kernel: 3.10.0-08587-g496322b #35 Not tainted
>>> Jul 10 11:40:44 x4 kernel: ------------------------------------------------
>>> Jul 10 11:40:44 x4 kernel: X/211 is leaving the kernel with locks still held!
>>> Jul 10 11:40:44 x4 kernel: 2 locks held by X/211:
>>> Jul 10 11:40:44 x4 kernel: #0: (reservation_ww_class_acquire){+.+.+.}, at: [<ffffffff813279f0>] radeon_bo_list_validate+0x20/0xd0
>>> Jul 10 11:40:44 x4 kernel: #1: (reservation_ww_class_mutex){+.+.+.}, at: [<ffffffff81309306>] ttm_eu_reserve_buffers+0x126/0x4b0
>>> Jul 10 11:40:52 x4 kernel: SysRq : Emergency Sync
>>> Jul 10 11:40:53 x4 kernel: Emergency Sync complete
>>>
>> Thanks, exactly what I thought. I missed a backoff somewhere..
>>
>> Does the below patch fix it?
> Yes. Thank you for your quick reply.
8<------
If radeon_cs_parser_relocs fails ttm_eu_backoff_reservation doesn't get called.
This left open a bug where ttm_eu_reserve_buffers succeeded but the bo's were
not unlocked afterwards:
Jul 10 11:40:44 x4 kernel: ================================================
Jul 10 11:40:44 x4 kernel: [ BUG: lock held when returning to user space! ]
Jul 10 11:40:44 x4 kernel: 3.10.0-08587-g496322b #35 Not tainted
Jul 10 11:40:44 x4 kernel: ------------------------------------------------
Jul 10 11:40:44 x4 kernel: X/211 is leaving the kernel with locks still held!
Jul 10 11:40:44 x4 kernel: 2 locks held by X/211:
Jul 10 11:40:44 x4 kernel: #0: (reservation_ww_class_acquire){+.+.+.}, at: [<ffffffff813279f0>] radeon_bo_list_validate+0x20/0xd0
Jul 10 11:40:44 x4 kernel: #1: (reservation_ww_class_mutex){+.+.+.}, at: [<ffffffff81309306>] ttm_eu_reserve_buffers+0x126/0x4b0
Jul 10 11:40:52 x4 kernel: SysRq : Emergency Sync
Jul 10 11:40:53 x4 kernel: Emergency Sync complete
This is a regression caused by commit ecff665f5e.
"drm/ttm: make ttm reservation calls behave like reservation calls"
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Lighter weight than using the 3D engine.
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Lighter weight than using the 3D engine.
v2: fix ring count
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
They still seem to cause instability on some r6xx parts.
As a follow up, we can switch to using CP DMA for bo
moves on r6xx as a lighter weight alternative to using
the 3D engine.
A version of this patch should also go to stable kernels.
Tested-by: J.N. <golden.fleeced@gmail.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Gfx PG doesn't seem to work properly when UVD is initialized
on certain PALM boards. Disable gfx PG for now until we sort
out a proper fix.
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Toghether with the hw state readout this should catch cases where we
don't properly updated the pll state (either in sw or hw). At least
for the shared dpll code the equivalent tricke helped a lot in
catching bugs.
Also rename the function prefix, it's not a generic piece of
infrastructure.
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Bspec for the "DPLL HDMI multiplier" field says:
"Restriction : The DPLL must be enabled and stable before setting these bits.
These bits must be programmed after DPLL_SEL is programmed."
There is apparently no restriction on programming the DPLL_SEL
register wrt the DPLL. So let's just move that up before we enable the
pch dpll.
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
No need to call the ->pre_pll_enable hook twice if we don't enable the
dpll too early. This should make Jani a bit less grumpy.
v2: Rebase on top of the newly-colored BUG_ONs.
v3: Reinstate the lost write of the DPLL_MD register, spotted by Imre.
Cc: Imre Deak <imre.deak@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Move error state generation and stringification to it's
own compilation unit. Sysfs also uses this so it can't be
under CONFIG_DEBUG_FS
This fixes a regression introduced in
commit ef86ddced7
Author: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Date: Thu Jun 6 17:38:54 2013 +0300
drm/i915: add error_state sysfs entry
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66814
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
If intel_sdvo_get_value() fails here, val is unitialized and the cross
check will compare the pipe config multiplier with a bogus value.
Instead, only set encoder_pixel_multiplier when the sdvo command has
been successful. The cross check will compare the pipe config value with
0 otherwise.
v2: Do the cross check with the initial value of encoder_pixel_multiplier (0)
if the sdvo command fails (and thus keep the warning) (Daniel Vetter)
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Came accross two open coding of for_each_pipe(), might as well use the
macro.
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The code to handle it is broken - there's simply no code to clear CS
parser errors on gen5+. And behold, for all the other rings we also
don't enable it!
Leave the handling code itself in place just to be consistent with the
existing mess though. And in case someone feels like fixing it all up.
This has been errornously enabled in
commit 12638c57f3
Author: Ben Widawsky <ben@bwidawsk.net>
Date: Tue May 28 19:22:31 2013 -0700
drm/i915: Enable vebox interrupts
Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Ben Widawsky <ben@bwidawsk.net>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
With the simplified locking there's no reason any more to keep the
refcounts seperate.
v2: Readd the lost comment that ring->irq_refcount is protected by
dev_priv->irq_lock.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Now that the rps interrupt locking isn't clearly separated (at elast
conceptually) from all the other interrupt locking having a different
lock stopped making sense: It protects much more than just the rps
workqueue it started out with. But with the addition of VECS the
separation started to blurr and resulted in some more complex locking
for the ring interrupt refcount.
With this we can (again) unifiy the ringbuffer irq refcounts without
causing a massive confusion, but that's for the next patch.
v2: Explain better why the rps.lock once made sense and why no longer,
requested by Ben.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
And kill the comment about it. Queueing work is a barrier type event,
no amount of locking will help in ordering things (as long as we queue
the work after having updated all relevant data structures). Also, the
queue_work works itself as a sufficient memory barrier.
Again on the surface this is just a tiny micro-optimization to reduce
the hold-time of dev_priv->irq_lock. But the better reason is that it
reduces superficial locking and so makes it clearer what we actually
need for correctness.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The if (pm_iir & ~GEN6_PM_RPS_EVENTS) check was redunandant. Otoh
adding a check for rps events allows us to avoid the spinlock grabbing
for VECS interrupts.
v2: Drop misplaced hunk which now moved to the right patch.
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Since we only have one interrupt handler and interrupt handlers are
non-reentrant.
To drive the point really home give them all an _irq_handler suffix.
This is a tiny micro-optimization but even more important it makes it
clearer what locking we actually need. And in case someone screws this
up: lockdep will catch hardirq vs. other context deadlocks.
v2: Fix up compile fail.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
It's racy: There's no guarantee that we won't walk this code (due to a
pch fifo underrun interrupt) while someone is changing the pointers
around.
The only reason we do this is to use the righ crtc for the pch fifo
underrun accounting. But we never expose this to userspace, so
essentially no one really cares if we use the "wrong" crtc.
So let's just rip it out.
With this patch fifo underrun code will always use crtc A for tracking
underruns on the (only) pch transcoder on LPT.
v2: Add a big comment explaining what's going on. Requested by Paulo.
v3: Fixup spelling in comment as spotted by Paulo.
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Same treatment as for SERR_INT: If we clear only the bit for the pipe
we're enabling (but unconditionally) then we can always check for
possible underruns after having disabled the interrupt. That way pipe
underruns won't be lost, but at worst only get reported in a delayed
fashion.
v2: The same logic bug as in the SERR handling change also existed
here. The same bugfix of only reporting missed underruns when the
error interrupt was masked applies, too.
v3: Do the same fixes as for the SERR handling that Paulo suggested in
his review:
- s/%i/%c/ fix in the debug output
- move the DE_ERR_INT_IVB read into the respective if block
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
[danvet: Fix up the checkpatch bikeshed Paulo noticed.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The current code won't report any fifo underruns on cpt if just one
pipe has fifo underrun reporting disabled. We can't enable the
interrupts, but we can still check the per-transcoder bits and so
report the underrun delayed if:
- We always clear the transcoder's bit (and none of the other bits)
when enabling.
- We check the transcoder's bit after disabling (to avoid racing with
the interrupt handler).
v2: I've forgotten to actually remove the old SERR_INT clearing.
v3: Use transcoder_name as suggested by Paulo Zanoni. Paulo also
noticed a logic bug: When an underrun interrupt fires we report it
both in the interrupt handler and when checking for underruns when
disabling it in cpt_set_fifo_underrun_reporting. But that second check
is only required if the interrupt is disabled and we're switching of
underrun reporting (e.g. because we're disabling the crtc). Hence
check for that condition.
At first I wanted to rework the code to pass that bit of information
from the uppper functions down to cpt_set_fifo_underrun_reporting. But
that turned out too messy. Hence the quick&dirty check whether the
south error interrupt source is masked off or not.
v4: Streamline the control flow a bit.
v5: s/pipe/pch transcoder/ in the dmesg output, suggested by Paulo.
v6: Review from Paulo:
- Reorder the was_enabled assignment to only read the register when we
need it. Also add a comment that we need to do that before updating
the register.
- s/%i/%c/ fix for the debug output.
- Fix the checkpath complaint in the SERR_INT_TRANS_FIFO_UNDERRUN
#define.
v7: Hopefully put that elusive SERR hunk back into this patch, spotted
by Paulo.
Cc: Paulo Zanoni <przanoni@gmail.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This way all changes to SDEIMR all go through the same function, with
the exception of the (single-threaded) setup/teardown code.
For paranoia again add an assert_spin_locked.
v2: For even more paranoia also sprinkle a spinlock assert over
cpt_can_enable_serr_int since we need to have that one there, too.
v3: Fix the logic of interrupt enabling, add enable/disable macros for
the simple cases in the fifo code and add a comment. All requested by
Paulo.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Use "const char *" instead of "char *" in order to avoid this warning:
drivers/gpu/drm/drm_edid_load.c: In function ‘drm_load_edid_firmware’:
drivers/gpu/drm/drm_edid_load.c:245:25: warning: initialization discards ‘const’ qualifier from pointer target type [enabled by default]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 25ff119 and the follow on for Valleyview commit 2dc8aae.
commit 25ff1195f8
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu Apr 4 21:31:03 2013 +0100
drm/i915: Workaround incoherence between fences and LLC across multiple CPUs
commit 2dc8aae06d
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed May 22 17:08:06 2013 +0100
drm/i915: Workaround incoherence with fence updates on Valleyview
Jon Bloomfield came up with a plausible explanation and cheap fix
(drm/i915: Fix incoherence with fence updates on Sandybridge+) for the
race condition, so lets run with it.
This is a candidate for stable as the old workaround incurs a
significant cost (calling wbinvd on all CPUs before performing the
register write) for some workloads as noted by Carsten Emde.
Link: http://lists.freedesktop.org/archives/intel-gfx/2013-June/028819.html
References: https://www.osadl.org/?id=1543#c7602
References: https://bugs.freedesktop.org/show_bug.cgi?id=63825
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jon Bloomfield <jon.bloomfield@intel.com>
Cc: Carsten Emde <C.Emde@osadl.org>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This hopefully fixes the root cause behind the workaround added in
commit 25ff1195f8
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu Apr 4 21:31:03 2013 +0100
drm/i915: Workaround incoherence between fences and LLC across multiple CPUs
Thanks to further investigation by Jon Bloomfield, he realised that
the 64-bit register might be broken up by the hardware into two 32-bit
writes (a problem we have encountered elsewhere). This non-atomicity
would then cause an issue where a second thread would see an
intermediate register state (new high dword, old low dword), and this
register would randomly be used in preference to its own thread register.
This would cause the second thread to read from and write into a fairly
random tiled location. Breaking the operation into 3 explicit 32-bit
updates (first disable the fence, poke the upper bits, then poke the lower
bits and enable) ensures that, given proper serialisation between the
32-bit register write and the memory transfer, that the fence value is
always consistent.
Armed with this knowledge, we can explain how the previous workaround
work. The key to the corruption is that a second thread sees an
erroneous fence register that conflicts and overrides its own. By
serialising the fence update across all CPUs, we have a small window
where no GTT access is occurring and so hide the potential corruption.
This also leads to the conclusion that the earlier workaround was
incomplete.
v2: Be overly paranoid about the order in which fence updates become
visible to the GPU to make really sure that we turn the fence off before
doing the update, and then only switch the fence on afterwards.
Signed-off-by: Jon Bloomfield <jon.bloomfield@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Carsten Emde <C.Emde@osadl.org>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
