[Intel-gfx] [PATCH 5/6] drm/i915/gen10: implement gen 10 watermarks calculations

Rodrigo Vivi rodrigo.vivi at intel.com
Wed Aug 9 20:52:47 UTC 2017


From: Paulo Zanoni <paulo.r.zanoni at intel.com>

They're slightly different than the gen 9 calculations.

v2: Remove TODO comment. Code matches recent spec.

Cc: Mahesh Kumar <mahesh1.kumar at intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
---
 drivers/gpu/drm/i915/intel_pm.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 1622e6f3c6b6..857e2f0a4b15 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4274,8 +4274,9 @@ skl_allocate_pipe_ddb(struct intel_crtc_state *cstate,
  * should allow pixel_rate up to ~2 GHz which seems sufficient since max
  * 2xcdclk is 1350 MHz and the pixel rate should never exceed that.
 */
-static uint_fixed_16_16_t skl_wm_method1(uint32_t pixel_rate, uint8_t cpp,
-					 uint32_t latency)
+static uint_fixed_16_16_t
+skl_wm_method1(const struct drm_i915_private *dev_priv, uint32_t pixel_rate,
+	       uint8_t cpp, uint32_t latency)
 {
 	uint32_t wm_intermediate_val;
 	uint_fixed_16_16_t ret;
@@ -4285,6 +4286,10 @@ static uint_fixed_16_16_t skl_wm_method1(uint32_t pixel_rate, uint8_t cpp,
 
 	wm_intermediate_val = latency * pixel_rate * cpp;
 	ret = div_fixed16(wm_intermediate_val, 1000 * 512);
+
+	if (INTEL_GEN(dev_priv) >= 10)
+		ret.val += 1 << 16;
+
 	return ret;
 }
 
@@ -4436,11 +4441,15 @@ static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv,
 
 	plane_bytes_per_line = width * cpp;
 	if (y_tiled) {
-		interm_pbpl = DIV_ROUND_UP(plane_bytes_per_line *
-					   y_min_scanlines, 512);
+		interm_pbpl = plane_bytes_per_line * y_min_scanlines;
+
+		if (INTEL_GEN(dev_priv) >= 10)
+			interm_pbpl++;
+
+		interm_pbpl = DIV_ROUND_UP(interm_pbpl, 512);
 		plane_blocks_per_line = div_fixed16(interm_pbpl,
 							y_min_scanlines);
-	} else if (x_tiled) {
+	} else if (x_tiled && INTEL_GEN(dev_priv) == 9) {
 		interm_pbpl = DIV_ROUND_UP(plane_bytes_per_line, 512);
 		plane_blocks_per_line = u32_to_fixed16(interm_pbpl);
 	} else {
@@ -4448,7 +4457,7 @@ static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv,
 		plane_blocks_per_line = u32_to_fixed16(interm_pbpl);
 	}
 
-	method1 = skl_wm_method1(plane_pixel_rate, cpp, latency);
+	method1 = skl_wm_method1(dev_priv, plane_pixel_rate, cpp, latency);
 	method2 = skl_wm_method2(plane_pixel_rate,
 				 cstate->base.adjusted_mode.crtc_htotal,
 				 latency,
-- 
2.13.2



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