diff mbox series

opp: Update bandwidth requirements based on scaling up/down

Message ID 8b523d9f7f0a00f4353cb2f0d6c8c3ab2b7c9324.1611828360.git.viresh.kumar@linaro.org
State Accepted
Commit 870d5d963972ddefa83a09a7dbe4bef01f0b35b8
Headers show
Series opp: Update bandwidth requirements based on scaling up/down | expand

Commit Message

Viresh Kumar Jan. 28, 2021, 10:06 a.m. UTC 
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 <digetx@gmail.com>
Reported-by: Akhil P Oommen <akhilpo@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>

---
 drivers/opp/core.c | 40 +++++++++++++++++++++++++++-------------
 1 file changed, 27 insertions(+), 13 deletions(-)

-- 
2.25.0.rc1.19.g042ed3e048af
diff mbox series

Patch

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index e03600547b98..a518173fd64a 100644
--- 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;
 }