soc: mediatek: svs: Add support for voltage bins

Add support voltage bins turn point
Signed-off-by: Mark Tseng <chun-jen.tseng@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230921052637.30444-4-chun-jen.tseng@mediatek.com

drivers/soc/mediatek/mtk-svs.c

@@ -407,6 +407,7 @@ struct svs_platform_data {
  * @dcbdet: svs efuse data
  * @dcmdet: svs efuse data
  * @turn_pt: 2-line turn point tells which opp_volt calculated by high/low bank
+ * @vbin_turn_pt: voltage bin turn point helps know which svsb_volt should be overridden
  * @type: bank type to represent it is 2-line (high/low) bank or 1-line bank
  *
  * Svs bank will generate suitalbe voltages by below general math equation
@@ -469,6 +470,7 @@ struct svs_bank {
 	u32 dcbdet;
 	u32 dcmdet;
 	u32 turn_pt;
+	u32 vbin_turn_pt;
 	u32 type;
 };
 
@@ -751,11 +753,12 @@ static int svs_status_debug_show(struct seq_file *m, void *v)
 
 	ret = thermal_zone_get_temp(svsb->tzd, &tzone_temp);
 	if (ret)
-		seq_printf(m, "%s: temperature ignore, turn_pt = %u\n",
-			   svsb->name, svsb->turn_pt);
+		seq_printf(m, "%s: temperature ignore, vbin_turn_pt = %u, turn_pt = %u\n",
+			   svsb->name, svsb->vbin_turn_pt, svsb->turn_pt);
 	else
-		seq_printf(m, "%s: temperature = %d, turn_pt = %u\n",
-			   svsb->name, tzone_temp, svsb->turn_pt);
+		seq_printf(m, "%s: temperature = %d, vbin_turn_pt = %u, turn_pt = %u\n",
+			   svsb->name, tzone_temp, svsb->vbin_turn_pt,
+			   svsb->turn_pt);
 
 	for (i = 0; i < svsb->opp_count; i++) {
 		opp = dev_pm_opp_find_freq_exact(svsb->opp_dev,
@@ -952,6 +955,29 @@ static void svs_get_bank_volts_v3(struct svs_platform *svsp)
 	for (i = opp_start; i < opp_stop; i++)
 		if (svsb->volt_flags & SVSB_REMOVE_DVTFIXED_VOLT)
 			svsb->volt[i] -= svsb->dvt_fixed;
+
+	/* For voltage bin support */
+	if (svsb->opp_dfreq[0] > svsb->freq_base) {
+		svsb->volt[0] = svs_opp_volt_to_bank_volt(svsb->opp_dvolt[0],
+							  svsb->volt_step,
+							  svsb->volt_base);
+
+		/* Find voltage bin turn point */
+		for (i = 0; i < svsb->opp_count; i++) {
+			if (svsb->opp_dfreq[i] <= svsb->freq_base) {
+				svsb->vbin_turn_pt = i;
+				break;
+			}
+		}
+
+		/* Override svs bank voltages */
+		for (i = 1; i < svsb->vbin_turn_pt; i++)
+			svsb->volt[i] = interpolate(svsb->freq_pct[0],
+						    svsb->freq_pct[svsb->vbin_turn_pt],
+						    svsb->volt[0],
+						    svsb->volt[svsb->vbin_turn_pt],
+						    svsb->freq_pct[i]);
+	}
 }
 
 static void svs_set_bank_freq_pct_v3(struct svs_platform *svsp)
@@ -1069,6 +1095,29 @@ static void svs_get_bank_volts_v2(struct svs_platform *svsp)
 
 	for (i = 0; i < svsb->opp_count; i++)
 		svsb->volt[i] += svsb->volt_od;
+
+	/* For voltage bin support */
+	if (svsb->opp_dfreq[0] > svsb->freq_base) {
+		svsb->volt[0] = svs_opp_volt_to_bank_volt(svsb->opp_dvolt[0],
+							  svsb->volt_step,
+							  svsb->volt_base);
+
+		/* Find voltage bin turn point */
+		for (i = 0; i < svsb->opp_count; i++) {
+			if (svsb->opp_dfreq[i] <= svsb->freq_base) {
+				svsb->vbin_turn_pt = i;
+				break;
+			}
+		}
+
+		/* Override svs bank voltages */
+		for (i = 1; i < svsb->vbin_turn_pt; i++)
+			svsb->volt[i] = interpolate(svsb->freq_pct[0],
+						    svsb->freq_pct[svsb->vbin_turn_pt],
+						    svsb->volt[0],
+						    svsb->volt[svsb->vbin_turn_pt],
+						    svsb->freq_pct[i]);
+	}
 }
 
 static void svs_set_bank_freq_pct_v2(struct svs_platform *svsp)