opp: Update bandwidth requirements based on scaling up/down

The bandwidth must be scaled at a different point in the code flow based on if we are scaling up or down the frequency, otherwise this may cause undesired effects as the device will try to use more of the memory bandwidth which may be shared across several devices. Much like how regulators and required-opps are programmed. Reported-by: Dmitry Osipenko <[email protected]> Reported-by: Akhil P Oommen <[email protected]> Signed-off-by: Viresh Kumar <[email protected]> Tested-by: Dmitry Osipenko <[email protected]>
c3550 · Feb 2, 2021 · 870d5d9 · 870d5d9
1 parent 7eba0c7
commit 870d5d9
Showing 1 changed file with 27 additions and 13 deletions.
diff --git a/drivers/opp/core.c b/drivers/opp/core.c
@@ -1015,8 +1015,16 @@ static int _set_opp(struct device *dev, struct opp_table *opp_table,
 	/* Scaling up? Configure required OPPs before frequency */
 	if (!scaling_down) {
 		ret = _set_required_opps(dev, opp_table, opp, true);
-		if (ret)
+		if (ret) {
+			dev_err(dev, "Failed to set required opps: %d\n", ret);
+			return ret;
+		}
+
+		ret = _set_opp_bw(opp_table, opp, dev);
+		if (ret) {
+			dev_err(dev, "Failed to set bw: %d\n", ret);
 			return ret;
+		}
 	}
 
 	if (opp_table->set_opp) {
@@ -1029,24 +1037,30 @@ static int _set_opp(struct device *dev, struct opp_table *opp_table,
 		ret = _generic_set_opp_clk_only(dev, opp_table->clk, freq);
 	}
 
+	if (ret)
+		return ret;
+
 	/* Scaling down? Configure required OPPs after frequency */
-	if (!ret && scaling_down) {
+	if (scaling_down) {
+		ret = _set_opp_bw(opp_table, opp, dev);
+		if (ret) {
+			dev_err(dev, "Failed to set bw: %d\n", ret);
+			return ret;
+		}
+
 		ret = _set_required_opps(dev, opp_table, opp, false);
-		if (ret)
+		if (ret) {
 			dev_err(dev, "Failed to set required opps: %d\n", ret);
+			return ret;
+		}
 	}
 
-	if (!ret) {
-		ret = _set_opp_bw(opp_table, opp, dev);
-		if (!ret) {
-			opp_table->enabled = true;
-			dev_pm_opp_put(old_opp);
+	opp_table->enabled = true;
+	dev_pm_opp_put(old_opp);
 
-			/* Make sure current_opp doesn't get freed */
-			dev_pm_opp_get(opp);
-			opp_table->current_opp = opp;
-		}
-	}
+	/* Make sure current_opp doesn't get freed */
+	dev_pm_opp_get(opp);
+	opp_table->current_opp = opp;
 
 	return ret;
 }