[PATCH 1/2] cpufreq: OMAP: Handle missing frequency table on SMP systems
From: Shilimkar, Santosh <hidden>
Date: 2012-08-08 11:30:10
Also in:
linux-omap
Subsystem:
cpu frequency scaling framework, the rest · Maintainers:
"Rafael J. Wysocki", Viresh Kumar, Linus Torvalds
On Wed, Aug 8, 2012 at 4:24 PM, Rajendra Nayak [off-list ref] wrote:
quoted hunk ↗ jump to hunk
On OMAP4, if the first CPU fails to get a valid frequency table (this could happen if the platform does not register any OPP table), the subsequent CPU instances end up dealing with a NULL freq_table and crash. Add a check for a NULL freq_table to help error the rest of the CPU instances out. Signed-off-by: Rajendra Nayak <redacted> Cc: <redacted> --- drivers/cpufreq/omap-cpufreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/drivers/cpufreq/omap-cpufreq.cb/drivers/cpufreq/omap-cpufreq.c index 17fa04d..0ee824c 100644--- a/drivers/cpufreq/omap-cpufreq.c +++ b/drivers/cpufreq/omap-cpufreq.c@@ -221,7 +221,7 @@ static int __cpuinit omap_cpu_init(structcpufreq_policy *policy) if (atomic_inc_return(&freq_table_users) == 1) result = opp_init_cpufreq_table(mpu_dev, &freq_table); - if (result) { + if (result || !freq_table) { dev_err(mpu_dev, "%s: cpu%d: failed creating freq table[%d]\n", __func__, policy->cpu, result); goto fail_ck;
The freq_table use count seems to be buggy in that case. Something like below should fix the issue. Feel free to update your patch with below if you agree.
diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c
index 17fa04d..fd97c3d 100644
--- a/drivers/cpufreq/omap-cpufreq.c
+++ b/drivers/cpufreq/omap-cpufreq.c@@ -218,7 +218,7 @@ static int __cpuinit omap_cpu_init(struct cpufreq_policy *po policy->cur = policy->min = policy->max = omap_getspeed(policy->cpu); - if (atomic_inc_return(&freq_table_users) == 1) + if (freq_table) result = opp_init_cpufreq_table(mpu_dev, &freq_table); if (result) {
@@ -227,6 +227,7 @@ static int __cpuinit omap_cpu_init(struct cpufreq_policy *po goto fail_ck; } + atomic_inc_return(&freq_table_users); result = cpufreq_frequency_table_cpuinfo(policy, freq_table); if (result) goto fail_table;