[PATCH 01/15] drm/i915: Allocate min dbuf blocks per bspec

Chandra Konduru
2015-09-05T02:34:54Z

Properly allocate min blocks per hw requirements.

v2:
- changed helper functional param to bool, some code simplification (Ville)

Signed-off-by: Chandra Konduru <chandra.konduru@intel.com>
---
drivers/gpu/drm/i915/intel_pm.c | 29 +++++++++++++++++++++++++++--
1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index fff0c22..4d3aca0 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2959,6 +2959,31 @@ skl_get_total_relative_data_rate(struct intel_crtc *intel_crtc,
return total_data_rate;
}

+static uint16_t
+skl_dbuf_min_alloc(const struct intel_plane_wm_parameters *p, bool y_plane)
+{
+ uint16_t min_alloc;
+
+ /* For packed formats, no y-plane, return 0 */
+ if (y_plane && !p->y_bytes_per_pixel)
+ return 0;
+
+ if (p->tiling == I915_FORMAT_MOD_Y_TILED ||
+ p->tiling == I915_FORMAT_MOD_Yf_TILED) {
+ uint32_t min_scanlines = 8;
+ uint8_t bytes_per_pixel =
+ y_plane ? p->y_bytes_per_pixel : p->bytes_per_pixel;
+
+ min_scanlines = 32 / bytes_per_pixel;
+ min_alloc = DIV_ROUND_UP((4 * p->horiz_pixels/(y_plane ? 1 : 2) *
+ bytes_per_pixel), 512) * min_scanlines/4 + 3;
+ } else {
+ min_alloc = 8;
+ }
+
+ return min_alloc;
+}
+
static void
skl_allocate_pipe_ddb(struct drm_crtc *crtc,
const struct intel_wm_config *config,
@@ -2999,9 +3024,9 @@ skl_allocate_pipe_ddb(struct drm_crtc *crtc,
if (!p->enabled)
continue;

- minimum[plane] = 8;
+ minimum[plane] = skl_dbuf_min_alloc(p, false); /* uv-plane/packed */
alloc_size -= minimum[plane];
- y_minimum[plane] = p->y_bytes_per_pixel ? 8 : 0;
+ y_minimum[plane] = skl_dbuf_min_alloc(p, true); /* y-plane */
alloc_size -= y_minimum[plane];
}

--
1.7.9.5