EXYNOS: bugfix on retrieving old_index from freqs.old
The policy might have been changed since last call of target().
Thus, using cpufreq_frequency_table_target(), which depends on
policy to find the corresponding index from a frequency, may return
inconsistent index for freqs.old. Thus, old_index should be
calculated not based on the current policy.
We have been observing such issue when scaling_min/max_freq were
updated and sometimes cuased system lockups deu to incorrectly
configured voltages.
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/cpufreq/exynos-cpufreq.c b/drivers/cpufreq/exynos-cpufreq.c
index b243a7e..af2d81e 100644
--- a/drivers/cpufreq/exynos-cpufreq.c
+++ b/drivers/cpufreq/exynos-cpufreq.c
@@ -62,8 +62,18 @@
goto out;
}
- if (cpufreq_frequency_table_target(policy, freq_table,
- freqs.old, relation, &old_index)) {
+ /*
+ * The policy max have been changed so that we cannot get proper
+ * old_index with cpufreq_frequency_table_target(). Thus, ignore
+ * policy and get the index from the raw freqeuncy table.
+ */
+ for (old_index = 0;
+ freq_table[old_index].frequency != CPUFREQ_TABLE_END;
+ old_index++)
+ if (freq_table[old_index].frequency == freqs.old)
+ break;
+
+ if (freq_table[old_index].frequency == CPUFREQ_TABLE_END) {
ret = -EINVAL;
goto out;
}