drm/i915/fbc: Align FBC segments to 512B on glk+

Apply the same 512 byte FBC segment alignment to glk+ as we use
on skl+. The only real difference is that we now have a dedicated
register for the FBC override stride. Not 100% sure which
platforms really need the 512B alignment, but it's easiest
to just do it on everything.

Also the hardware no longer seems to misclaculate the CFB stride
for linear, so we can omit the use of the override stride for
linear unless the stride is misaligned.
Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210921152517.803-3-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/display/intel_fbc.c

@@ -115,7 +115,7 @@ static unsigned int intel_fbc_cfb_stride(struct drm_i915_private *i915,
 	 * be 512 byte aligned. Aligning each line to 512 bytes guarantees
 	 * that regardless of the compression limit we choose later.
 	 */
-	if (DISPLAY_VER(i915) == 9)
+	if (DISPLAY_VER(i915) >= 9)
 		return max(ALIGN(stride, 512), skl_fbc_min_cfb_stride(cache));
 	else
 		return stride;
@@ -356,10 +356,18 @@ static void gen7_fbc_activate(struct drm_i915_private *dev_priv)
 	const struct intel_fbc_reg_params *params = &fbc->params;
 	u32 dpfc_ctl;
 
-	/* Display WA #0529: skl, kbl, bxt. */
-	if (DISPLAY_VER(dev_priv) == 9) {
+	if (DISPLAY_VER(dev_priv) >= 10) {
+		u32 val = 0;
+
+		if (params->override_cfb_stride)
+			val |= FBC_STRIDE_OVERRIDE |
+				FBC_STRIDE(params->override_cfb_stride / fbc->limit);
+
+		intel_de_write(dev_priv, GLK_FBC_STRIDE, val);
+	} else if (DISPLAY_VER(dev_priv) == 9) {
 		u32 val = 0;
 
+		/* Display WA #0529: skl, kbl, bxt. */
 		if (params->override_cfb_stride)
 			val |= CHICKEN_FBC_STRIDE_OVERRIDE |
 				CHICKEN_FBC_STRIDE(params->override_cfb_stride / fbc->limit);

drivers/gpu/drm/i915/i915_reg.h

@@ -3360,6 +3360,10 @@ static inline bool i915_mmio_reg_valid(i915_reg_t reg)
 #define   ILK_DPFC_DISABLE_DUMMY0 (1 << 8)
 #define   ILK_DPFC_CHICKEN_COMP_DUMMY_PIXEL	(1 << 14)
 #define   ILK_DPFC_NUKE_ON_ANY_MODIFICATION	(1 << 23)
+#define GLK_FBC_STRIDE		_MMIO(0x43228)
+#define   FBC_STRIDE_OVERRIDE	REG_BIT(15)
+#define   FBC_STRIDE_MASK	REG_GENMASK(14, 0)
+#define   FBC_STRIDE(x)		REG_FIELD_PREP(FBC_STRIDE_MASK, (x))
 #define ILK_FBC_RT_BASE		_MMIO(0x2128)
 #define   ILK_FBC_RT_VALID	(1 << 0)
 #define   SNB_FBC_FRONT_BUFFER	(1 << 1)