This is a note to let you know that I've just added the patch titled
drm/i915: Remove non-existent pipes from bigjoiner pipe mask
to the 6.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-i915-remove-non-existent-pipes-from-bigjoiner-pipe-mask.patch
and it can be found in the queue-6.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 3c1ea6a5f4f55d4e376675dda16945eb5d9bb4de Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@xxxxxxxxxxxxxxx>
Date: Fri, 18 Nov 2022 20:52:01 +0200
Subject: drm/i915: Remove non-existent pipes from bigjoiner pipe mask
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From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
commit 3c1ea6a5f4f55d4e376675dda16945eb5d9bb4de upstream.
bigjoiner_pipes() doesn't consider that:
- RKL only has three pipes
- some pipes may be fused off
This means that intel_atomic_check_bigjoiner() won't reject
all configurations that would need a non-existent pipe.
Instead we just keep on rolling witout actually having
reserved the slave pipe we need.
It's possible that we don't outright explode anywhere due to
this since eg. for_each_intel_crtc_in_pipe_mask() will only
walk the crtcs we've registered even though the passed in
pipe_mask asks for more of them. But clearly the thing won't
do what is expected of it when the required pipes are not
present.
Fix the problem by consulting the device info pipe_mask already
in bigjoiner_pipes().
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20221118185201.10469-1-ville.syrjala@xxxxxxxxxxxxxxx
Reviewed-by: Arun R Murthy <arun.r.murthy@xxxxxxxxx>
(cherry picked from commit f1c87a94a1087a26f41007ee83264033007421b5)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_display.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -3717,12 +3717,16 @@ out:
static u8 bigjoiner_pipes(struct drm_i915_private *i915)
{
+ u8 pipes;
+
if (DISPLAY_VER(i915) >= 12)
- return BIT(PIPE_A) | BIT(PIPE_B) | BIT(PIPE_C) | BIT(PIPE_D);
+ pipes = BIT(PIPE_A) | BIT(PIPE_B) | BIT(PIPE_C) | BIT(PIPE_D);
else if (DISPLAY_VER(i915) >= 11)
- return BIT(PIPE_B) | BIT(PIPE_C);
+ pipes = BIT(PIPE_B) | BIT(PIPE_C);
else
- return 0;
+ pipes = 0;
+
+ return pipes & RUNTIME_INFO(i915)->pipe_mask;
}
static bool transcoder_ddi_func_is_enabled(struct drm_i915_private *dev_priv,
Patches currently in stable-queue which might be from ville.syrjala@xxxxxxxxxxxxxxx are
queue-6.0/drm-i915-remove-non-existent-pipes-from-bigjoiner-pipe-mask.patch
