drm/i915/adlp: Fix register corruption after DDI clock enabling

From Imre Deak
59207e63801fbcd39ca68df6e2ba5ae90f76c0c3 in mainline linux

diff --git a/sys/dev/pci/drm/i915/i915_reg.h b/sys/dev/pci/drm/i915/i915_reg.h
index 9846d9a..7e56e3d 100644 (file)
--- a/sys/dev/pci/drm/i915/i915_reg.h
+++ b/sys/dev/pci/drm/i915/i915_reg.h
@@ -8308,6 +8308,7 @@ enum {
 #define   ICL_DELAY_PMRSP              REG_BIT(22)
 #define   DISABLE_FLR_SRC              REG_BIT(15)
 #define   MASK_WAKEMEM                 REG_BIT(13)
+#define   DDI_CLOCK_REG_ACCESS         REG_BIT(7)
 
 #define GEN11_CHICKEN_DCPR_2                   _MMIO(0x46434)
 #define   DCPR_MASK_MAXLATENCY_MEMUP_CLR       REG_BIT(27)

diff --git a/sys/dev/pci/drm/i915/intel_pm.c b/sys/dev/pci/drm/i915/intel_pm.c
index a1417ed..e678740 100644 (file)
--- a/sys/dev/pci/drm/i915/intel_pm.c
+++ b/sys/dev/pci/drm/i915/intel_pm.c
@@ -7606,6 +7606,9 @@ static void adlp_init_clock_gating(struct drm_i915_private *dev_priv)
 
        /* Wa_22011091694:adlp */
        intel_de_rmw(dev_priv, GEN9_CLKGATE_DIS_5, 0, DPCE_GATING_DIS);
+
+       /* Bspec/49189 Initialize Sequence */
+       intel_de_rmw(dev_priv, GEN8_CHICKEN_DCPR_1, DDI_CLOCK_REG_ACCESS, 0);
 }
 
 static void dg1_init_clock_gating(struct drm_i915_private *dev_priv)