[PATCH 5.16 0873/1017] drm/i915: Fix PSF GV point mask when SAGV is not possible

From: Greg Kroah-Hartman
Date: Tue Apr 05 2022 - 09:42:39 EST

From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>

commit 3ef8b5e19ead5a79600ea55f9549658281415893 upstream.

Don't just mask off all the PSF GV points when SAGV gets disabled.
This should in fact cause the Pcode to reject the request since
at least one PSF point must remain enabled at all times.

Cc: stable@xxxxxxxxxxxxxxx
Cc: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx>
Fixes: 192fbfb76744 ("drm/i915: Implement PSF GV point support")
Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20220309164948.10671-7-ville.syrjala@xxxxxxxxxxxxxxx
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx>
(cherry picked from commit 0fed4ddd18f064d2359b430c6e83ee60dd1f49b1)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
drivers/gpu/drm/i915/display/intel_bw.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/i915/display/intel_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_bw.c
@@ -819,7 +819,8 @@ int intel_bw_atomic_check(struct intel_a
* cause.
if (!intel_can_enable_sagv(dev_priv, new_bw_state)) {
- allowed_points = BIT(max_bw_point);
+ allowed_points &= ADLS_PSF_PT_MASK;
+ allowed_points |= BIT(max_bw_point);
drm_dbg_kms(&dev_priv->drm, "No SAGV, using single QGV point %d\n",