Ever since I started working on FBC I was already aware that FBC can
really amplify the FIFO underrun symptoms. On systems where FIFO
underruns were harmless error messages, enabling FBC would cause the
underruns to give black screens.
We recently tried to enable FBC on Haswell and got reports of a system
that would hang after some hours of uptime, and the first bad commit
was the one that enabled FBC. We also observed that this system had
FIFO underrun error messages on its dmesg. Although we don't have any
evidence that fixing the underruns would solve the bug and make FBC
work properly on this machine, IMHO it's better if we minimize the
amount of possible problems by just giving up FBC whenever we detect
an underrun.
v2: New version, different implementation and commit message.
v3: Clarify the fact that we run from an IRQ handler (Chris).
v4: Also add the underrun_detected check at can_choose() to avoid
misleading dmesg messages (DK).
v5: Fix Engrish, use READ_ONCE on the unlocked read (Chris).
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Lyude <cpaul@redhat.com>
Cc: stevenhoneyman@gmail.com <stevenhoneyman@gmail.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1473773937-19758-1-git-send-email-paulo.r.zanoni@intel.com
Since drm_i915_private is now a subclass of drm_device we do not need to
chase the drm_i915_private->dev backpointer and can instead simply
access drm_i915_private->drm directly.
text data bss dec hex filename
1068757 4565 416 1073738 10624a drivers/gpu/drm/i915/i915.ko
1066949 4565 416 1071930 105b3a drivers/gpu/drm/i915/i915.ko
Created by the coccinelle script:
@@
struct drm_i915_private *d;
identifier i;
@@
(
- d->dev->i
+ d->drm.i
|
- d->dev
+ &d->drm
)
and for good measure the dev_priv->dev backpointer was removed entirely.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1467711623-2905-4-git-send-email-chris@chris-wilson.co.uk
Since we now subclass struct drm_device, we can save pointer dances by
noting the equivalence of struct drm_device and struct drm_i915_private,
i.e. by using to_i915().
text data bss dec hex filename
1073824 4562 416 1078802 107612 drivers/gpu/drm/i915/i915.ko
1068976 4562 416 1073954 106322 drivers/gpu/drm/i915/i915.ko
Created by the coccinelle script:
@@
expression E;
identifier p;
@@
- struct drm_i915_private *p = E->dev_private;
+ struct drm_i915_private *p = to_i915(E);
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Dave Gordon <david.s.gordon@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1467628477-25379-1-git-send-email-chris@chris-wilson.co.uk
dev_priv is what the macro works hard to extract, pass it directly.
> sed 's/\([A-Z].*(dev_priv\)->dev)/\1)/g'
v2:
- Include all wrapper macros too (Chris)
v3:
- Include sed cmdline (Chris)
v4:
- Break long line
- Rebase
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1460016485-8089-1-git-send-email-joonas.lahtinen@linux.intel.com
ironlake_{enable,disable}_display_irq() each just call
ilk_update_display_irq() so let's make them static inlines.
While at it s/ironlake/ilk/ to make things shorter, and a bit more
consistent with the ibx functions.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1448294777-13722-3-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Make I915_READ and I915_WRITE more type safe by wrapping the register
offset in a struct. This should eliminate most of the fumbles we've had
with misplaced parens.
This only takes care of normal mmio registers. We could extend the idea
to other register types and define each with its own struct. That way
you wouldn't be able to accidentally pass the wrong thing to a specific
register access function.
The gpio_reg setup is probably the ugliest thing left. But I figure I'd
just leave it for now, and wait for some divine inspiration to strike
before making it nice.
As for the generated code, it's actually a bit better sometimes. Eg.
looking at i915_irq_handler(), we can see the following change:
lea 0x70024(%rdx,%rax,1),%r9d
mov $0x1,%edx
- movslq %r9d,%r9
- mov %r9,%rsi
- mov %r9,-0x58(%rbp)
- callq *0xd8(%rbx)
+ mov %r9d,%esi
+ mov %r9d,-0x48(%rbp)
callq *0xd8(%rbx)
So previously gcc thought the register offset might be signed and
decided to sign extend it, just in case. The rest appears to be
mostly just minor shuffling of instructions.
v2: i915_mmio_reg_{offset,equal,valid}() helpers added
s/_REG/_MMIO/ in the register defines
mo more switch statements left to worry about
ring_emit stuff got sorted in a prep patch
cmd parser, lrc context and w/a batch buildup also in prep patch
vgpu stuff cleaned up and moved to a prep patch
all other unrelated changes split out
v3: Rebased due to BXT DSI/BLC, MOCS, etc.
v4: Rebased due to churn, s/i915_mmio_reg_t/i915_reg_t/
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1447853606-2751-1-git-send-email-ville.syrjala@linux.intel.com
Due to the shared error interrupt on IVB/HSW and CPT/PPT we may not
always get an interrupt on a FIFO underrun. But we can always do an
explicit check (like we do on GMCH platforms that have no underrun
interrupt).
v2: Drop stale kerneldoc for i9xx_check_fifo_underruns() (Daniel)
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1446225741-11070-1-git-send-email-ville.syrjala@linux.intel.com
When we takeover from the BIOS and install our interrupt handler, the
BIOS may have left us a few surprises in the form of spontaneous
interrupts. (This is especially likely on hardware like 965gm where
display fifo underruns are continuous and the GMCH cannot filter that
interrupt souce.) As we enable our IRQ early so that we can use it
during hardware probing, our interrupt handler must be prepared to
handle a few sources prior to being fully configured. As such, we need
to add a simple is-ready check prior to dereferencing our KMS state for
reporting underruns.
Reported-by: Rob Clark <rclark@redhat.com>
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1193972
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
[Jani: dropped the extra !]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
The comment for intel_cpu_fifo_underrun_irq_handler() is not consistent
with the code and the rest of the comment for this routine. This patch
fixes this typo in comment.
Signed-off-by: Kumar Amit Mehta <gmate.amit@gmail.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This simplifies the code in the vlv irq handler. Also this now
means that we correctly filter underruns on gen2-4.
And as the real upshot I need to document one less function for
the fifo underrun code.
v2: Shorten one long line.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Way too much copypasta all over. And this also clarifies a bit what's
going on since it separates the "do we have an underrun irq" from the
"should we report the underrun" check.
v2: Fix excessively long lines.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Prep work for some nice documentation. Requires that we export the
display irq enable/disable functions on ilk/ibx. But we already export
them for vlv/i915. So not more inconsistency.
v2: Rebase on top of skl stage 1.
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>