Problem is that on some platforms, we do get QGV point mask in wrong
state on boot. However driver assumes it is set to 0
(i.e all points allowed), however in reality we might get them all restricted,
causing issues.
Lets disable SAGV initially to force proper QGV point state.
If more QGV points are available, driver will recalculate and update
those then after next commit.
v2: - Added trace to see which QGV/PSF GV point is used when SAGV is
disabled.
v3: - Move force disable function to intel_bw_init in order to initialize
bw state as well, so that hw/sw are immediately in sync after init.
v4: - Don't try sending PCode request, seems like it is not possible at
intel_bw_init, however assigning bw->state to be restricted as if
SAGV is off, still forces driveer to send PCode request anyway on
next modeset, so the solution still works.
However we still need to address the case, when no display is connected,
which anyway requires much more changes.
Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy@xxxxxxxxx>
---
drivers/gpu/drm/i915/display/intel_bw.c | 24 ++++++++++++++++++++++++
drivers/gpu/drm/i915/display/intel_bw.h | 2 ++
2 files changed, 26 insertions(+)
diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
index 7baa1c13eccd..36a6304207ba 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_bw.c
@@ -852,6 +852,27 @@ static unsigned int icl_max_bw_qgv_point(struct drm_i915_private *i915,
return max_bw_point;
}
+void icl_force_disable_sagv(struct drm_i915_private *i915, struct intel_bw_state *bw_state)
+{
+ unsigned int max_bw_qgv_point = icl_max_bw_qgv_point(i915, 0);
+ unsigned int qgv_points;
+ unsigned int psf_points;
+
+ qgv_points = BIT(max_bw_qgv_point);
+
+ /*
+ * We don't restrict PSF GV points, when disabling SAGV
+ */
+ psf_points = 0;
+
+ bw_state->qgv_points_mask = ~(ICL_PCODE_REQ_QGV_PT(qgv_points) |
+ ADLS_PCODE_REQ_PSF_PT(psf_points)) &
+ icl_qgv_points_mask(i915);
+
+ drm_dbg_kms(&i915->drm, "Forcing SAGV disable: leaving QGV point %d\n",
+ max_bw_qgv_point);
+}
+
static int mtl_find_qgv_points(struct drm_i915_private *i915,
unsigned int data_rate,
unsigned int num_active_planes,
@@ -1351,5 +1372,8 @@ int intel_bw_init(struct drm_i915_private *dev_priv)
intel_atomic_global_obj_init(dev_priv, &dev_priv->display.bw.obj,
&state->base, &intel_bw_funcs);
+ if (DISPLAY_VER(dev_priv) < 14)
+ icl_force_disable_sagv(dev_priv, state);
+
return 0;
}
diff --git a/drivers/gpu/drm/i915/display/intel_bw.h b/drivers/gpu/drm/i915/display/intel_bw.h
index 59cb4fc5db76..243192fd4cae 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.h
+++ b/drivers/gpu/drm/i915/display/intel_bw.h
@@ -74,5 +74,7 @@ int intel_bw_calc_min_cdclk(struct intel_atomic_state *state,
bool *need_cdclk_calc);
int intel_bw_min_cdclk(struct drm_i915_private *i915,
const struct intel_bw_state *bw_state);
+void icl_force_disable_sagv(struct drm_i915_private *dev_priv,
+ struct intel_bw_state *bw_state);
#endif /* __INTEL_BW_H__ */
--
2.37.3
