drm/i915: store the peak bw per QGV point

In MTL onwards, pcode locks the GV point based on the peak BW
of a QGV point. So store the peak BW of all the QGV points.

v2: use DIV_ROUND_CLOSEST() for the peakBW calculation

Bspec: 64636
Signed-off-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230606093509.221709-4-vinod.govindapillai@intel.com

drivers/gpu/drm/i915/display/intel_bw.c

@@ -534,10 +534,14 @@ static int tgl_get_bw_info(struct drm_i915_private *dev_priv, const struct intel
 
 			bi->deratedbw[j] = min(maxdebw,
 					       bw * (100 - sa->derating) / 100);
+			bi->peakbw[j] = DIV_ROUND_CLOSEST(sp->dclk *
+							  num_channels *
+							  qi.channel_width, 8);
 
 			drm_dbg_kms(&dev_priv->drm,
-				    "BW%d / QGV %d: num_planes=%d deratedbw=%u\n",
-				    i, j, bi->num_planes, bi->deratedbw[j]);
+				    "BW%d / QGV %d: num_planes=%d deratedbw=%u peakbw: %u\n",
+				    i, j, bi->num_planes, bi->deratedbw[j],
+				    bi->peakbw[j]);
 		}
 
 		for (j = 0; j < qi.num_psf_points; j++) {

drivers/gpu/drm/i915/display/intel_display_core.h

@@ -314,6 +314,8 @@ struct intel_display {
 			unsigned int deratedbw[I915_NUM_QGV_POINTS];
 			/* for each PSF GV point */
 			unsigned int psf_bw[I915_NUM_PSF_GV_POINTS];
+			/* Peak BW for each QGV point */
+			unsigned int peakbw[I915_NUM_QGV_POINTS];
 			u8 num_qgv_points;
 			u8 num_psf_gv_points;
 			u8 num_planes;