[Intel-gfx] [PATCH v3 3/4] drm/i915/fbc: Implement Wa_16011863758 for icl+

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

There's some kind of weird corner cases in FBC which requires
FBC segments to be separated by at least one extra cacheline.
Make sure that is present.

v2: Respin to fit in with skl_fbc_min_cfb_stride()
v3: Make it build

Reviewed-by: Juha-Pekka Heikkila <juhapekka.heikkila at gmail.com> #v1
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_fbc.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
index ff05eb83e204..2df6a4e115a1 100644
--- a/drivers/gpu/drm/i915/display/intel_fbc.c
+++ b/drivers/gpu/drm/i915/display/intel_fbc.c
@@ -84,7 +84,8 @@ static unsigned int _intel_fbc_cfb_stride(const struct intel_fbc_state_cache *ca
 }
 
 /* minimum acceptable cfb stride in bytes, assuming 1:1 compression limit */
-static unsigned int skl_fbc_min_cfb_stride(const struct intel_fbc_state_cache *cache)
+static unsigned int skl_fbc_min_cfb_stride(struct drm_i915_private *i915,
+					   const struct intel_fbc_state_cache *cache)
 {
 	unsigned int limit = 4; /* 1:4 compression limit is the worst case */
 	unsigned int cpp = 4; /* FBC always 4 bytes per pixel */
@@ -94,6 +95,13 @@ static unsigned int skl_fbc_min_cfb_stride(const struct intel_fbc_state_cache *c
 	/* minimum segment stride we can use */
 	stride = cache->plane.src_w * cpp * height / limit;
 
+	/*
+	 * Wa_16011863758: icl+
+	 * Avoid some hardware segment address miscalculation.
+	 */
+	if (DISPLAY_VER(i915) >= 11)
+		stride += 64;
+
 	/*
 	 * At least some of the platforms require each 4 line segment to
 	 * be 512 byte aligned. Just do it always for simplicity.
@@ -116,7 +124,7 @@ static unsigned int intel_fbc_cfb_stride(struct drm_i915_private *i915,
 	 * that regardless of the compression limit we choose later.
 	 */
 	if (DISPLAY_VER(i915) >= 9)
-		return max(ALIGN(stride, 512), skl_fbc_min_cfb_stride(cache));
+		return max(ALIGN(stride, 512), skl_fbc_min_cfb_stride(i915, cache));
 	else
 		return stride;
 }
-- 
2.32.0