We forgot the "res_blocks += y_tile_minimum" that's described on step V of our documentation. Again, this should only affect the Y tiling cases. It looks like the relevant code was introduced in 0fda65680e92, but there's always the possibility that it matched our specification when it was introduced, and then the specification changed while the code stayed the same. So we can't really say this was a regression, but let's try to add a "Fixes" tag anyway to help backporting. v2: Try to add a "Fixes" tag (Maarten). Fixes: 0fda65680e92 ("drm/i915/skl: Update watermarks for Y tiling") Cc: stable@xxxxxxxxxxxxxxx Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> Reviewed-by: Lyude <cpaul@xxxxxxxxxx> Reviewed-by: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx> Signed-off-by: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_pm.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index a6ae7b7..0957f5f 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -3552,7 +3552,7 @@ static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv, uint8_t cpp; uint32_t width = 0, height = 0; uint32_t plane_pixel_rate; - uint32_t y_min_scanlines; + uint32_t y_tile_minimum, y_min_scanlines; if (latency == 0 || !cstate->base.active || !intel_pstate->base.visible) { *enabled = false; @@ -3609,10 +3609,10 @@ static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv, latency, plane_blocks_per_line); + y_tile_minimum = plane_blocks_per_line * y_min_scanlines; + if (fb->modifier[0] == I915_FORMAT_MOD_Y_TILED || fb->modifier[0] == I915_FORMAT_MOD_Yf_TILED) { - uint32_t y_tile_minimum = plane_blocks_per_line * - y_min_scanlines; selected_result = max(method2, y_tile_minimum); } else { if ((ddb_allocation / plane_blocks_per_line) >= 1) @@ -3626,10 +3626,12 @@ static int skl_compute_plane_wm(const struct drm_i915_private *dev_priv, if (level >= 1 && level <= 7) { if (fb->modifier[0] == I915_FORMAT_MOD_Y_TILED || - fb->modifier[0] == I915_FORMAT_MOD_Yf_TILED) + fb->modifier[0] == I915_FORMAT_MOD_Yf_TILED) { + res_blocks += y_tile_minimum; res_lines += y_min_scanlines; - else + } else { res_blocks++; + } } if (res_blocks >= ddb_allocation || res_lines > 31) { -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html