linux-kernel - [PATCH] PM / OPP: Update performance state when freq == old

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Message-Id: <5a0c96bebb52c1ae34a2d0df63517b2d2938369c.1552366620.git.viresh.kumar@linaro.org>
Date:   Tue, 12 Mar 2019 10:27:18 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Rafael Wysocki <rjw@...ysocki.net>,
        Viresh Kumar <vireshk@...nel.org>, Nishanth Menon <nm@...com>,
        Stephen Boyd <sboyd@...nel.org>
Cc:     Viresh Kumar <viresh.kumar@...aro.org>, linux-pm@...r.kernel.org,
        Vincent Guittot <vincent.guittot@...aro.org>,
        jorge.ramirez-ortiz@...aro.org, "v5 . 0" <stable@...r.kernel.org>,
        Niklas Cassel <niklas.cassel@...aro.org>,
        linux-kernel@...r.kernel.org
Subject: [PATCH] PM / OPP: Update performance state when freq == old_freq

At boot up, CPUfreq core performs a sanity check to see if the system is
running at a frequency defined in the frequency table of the CPU. If so,
we try to find a valid frequency (lowest frequency greater than the
currently programmed frequency) from the table and set it. When the call
reaches dev_pm_opp_set_rate(), it calls _find_freq_ceil(opp_table,
&old_freq) to find the previously configured OPP and this call also
updates the old_freq. This eventually sets the old_freq == freq (new
target requested by cpufreq core) and we skip updating the performance
state in this case.

Fix this by also updating the performance state when the old_freq ==
freq.

Fixes: ca1b5d77b1c6 ("OPP: Configure all required OPPs")
Cc: v5.0 <stable@...r.kernel.org> # v5.0
Reported-by: Niklas Cassel <niklas.cassel@...aro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@...aro.org>
---
 drivers/opp/core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index d7f97167cac3..0420f7e8ad5b 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -760,7 +760,7 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
 		old_freq, freq);

 	/* Scaling up? Configure required OPPs before frequency */
-	if (freq > old_freq) {
+	if (freq >= old_freq) {
 		ret = _set_required_opps(dev, opp_table, opp);
 		if (ret)
 			goto put_opp;
-- 
2.21.0.rc0.269.g1a574e7a288b