[Intel-gfx] [PATCH v2 16/21] drm/i915/mtl: Update memory bandwidth parameters

Radhakrishna Sripada radhakrishna.sripada at intel.com
Thu Aug 18 23:41:57 UTC 2022


Like ADL_P, Meteorlake has different memory characteristics from
past platforms. Update the values used by our memory bandwidth
calculations accordingly.

Bspec: 64631

Reviewed-by: Matt Roper <matthew.d.roper at intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada at intel.com>
Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/display/intel_bw.c | 40 +++++++++++++++++++++++--
 1 file changed, 37 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_bw.c b/drivers/gpu/drm/i915/display/intel_bw.c
index 46b63afd536a..0182f0948fb9 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.c
+++ b/drivers/gpu/drm/i915/display/intel_bw.c
@@ -183,7 +183,32 @@ static int icl_get_qgv_points(struct drm_i915_private *dev_priv,
 	qi->num_points = dram_info->num_qgv_points;
 	qi->num_psf_points = dram_info->num_psf_gv_points;
 
-	if (DISPLAY_VER(dev_priv) >= 12)
+	if (DISPLAY_VER(dev_priv) >= 14) {
+		switch (dram_info->type) {
+		case INTEL_DRAM_DDR4:
+			qi->t_bl = 4;
+			qi->max_numchannels = 2;
+			qi->channel_width = 64;
+			qi->deinterleave = 2;
+			break;
+		case INTEL_DRAM_DDR5:
+			qi->t_bl = 8;
+			qi->max_numchannels = 4;
+			qi->channel_width = 32;
+			qi->deinterleave = 2;
+			break;
+		case INTEL_DRAM_LPDDR4:
+		case INTEL_DRAM_LPDDR5:
+			qi->t_bl = 16;
+			qi->max_numchannels = 8;
+			qi->channel_width = 16;
+			qi->deinterleave = 4;
+			break;
+		default:
+			MISSING_CASE(dram_info->type);
+			return -EINVAL;
+		}
+	} else if (DISPLAY_VER(dev_priv) >= 12) {
 		switch (dram_info->type) {
 		case INTEL_DRAM_DDR4:
 			qi->t_bl = is_y_tile ? 8 : 4;
@@ -217,7 +242,7 @@ static int icl_get_qgv_points(struct drm_i915_private *dev_priv,
 			qi->max_numchannels = 1;
 			break;
 		}
-	else if (DISPLAY_VER(dev_priv) == 11) {
+	} else if (DISPLAY_VER(dev_priv) == 11) {
 		qi->t_bl = dev_priv->dram_info.type == INTEL_DRAM_DDR4 ? 4 : 8;
 		qi->max_numchannels = 1;
 	}
@@ -316,6 +341,13 @@ static const struct intel_sa_info adlp_sa_info = {
 	.derating = 20,
 };
 
+static const struct intel_sa_info mtl_sa_info = {
+	.deburst = 32,
+	.deprogbwlimit = 38, /* GB/s */
+	.displayrtids = 256,
+	.derating = 20,
+};
+
 static int icl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel_sa_info *sa)
 {
 	struct intel_qgv_info qi = {};
@@ -590,7 +622,9 @@ void intel_bw_init_hw(struct drm_i915_private *dev_priv)
 	if (!HAS_DISPLAY(dev_priv))
 		return;
 
-	if (IS_DG2(dev_priv))
+	if (DISPLAY_VER(dev_priv) >= 14)
+		tgl_get_bw_info(dev_priv, &mtl_sa_info);
+	else if (IS_DG2(dev_priv))
 		dg2_get_bw_info(dev_priv);
 	else if (IS_ALDERLAKE_P(dev_priv))
 		tgl_get_bw_info(dev_priv, &adlp_sa_info);
-- 
2.25.1



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