[PATCH 5.4 69/80] drm/i915/fbc: Disable fbc by default on all glk+

From: Greg Kroah-Hartman
Date: Thu Dec 19 2019 - 13:56:10 EST


From: Ville SyrjÃlà <ville.syrjala@xxxxxxxxxxxxxxx>

commit 0eb8e74f7202a4a98bbc0c1adeed3986cf50b66a upstream.

We're missing a workaround in the fbc code for all glk+ platforms
which can cause corruption around the top of the screen. So
enabling fbc by default is a bad idea. I'm not keen to backport
the w/a so let's start by disabling fbc by default on all glk+.
We'll lift the restriction once the w/a is in place.

Cc: stable@xxxxxxxxxxxxxxx
Cc: Daniel Drake <drake@xxxxxxxxxxxx>
Cc: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx>
Cc: Jian-Hong Pan <jian-hong@xxxxxxxxxxxx>
Cc: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
Signed-off-by: Ville SyrjÃlà <ville.syrjala@xxxxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20191127201222.16669-2-ville.syrjala@xxxxxxxxxxxxxxx
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
(cherry picked from commit cd8c021b36a66833cefe2c90a79a9e312a2a5690)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/i915/display/intel_fbc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/i915/display/intel_fbc.c
+++ b/drivers/gpu/drm/i915/display/intel_fbc.c
@@ -1284,7 +1284,7 @@ static int intel_sanitize_fbc_option(str
return 0;

/* https://bugs.freedesktop.org/show_bug.cgi?id=108085 */
- if (IS_GEMINILAKE(dev_priv))
+ if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv))
return 0;

if (IS_BROADWELL(dev_priv) || INTEL_GEN(dev_priv) >= 9)