During frequency transitions, the cpufreq core takes the responsibility of
invoking cpufreq_freq_transition_begin() and cpufreq_freq_transition_end()
for those cpufreq drivers that define the ->target_index callback but don't
set the ASYNC_NOTIFICATION flag.
The powernow-k7 cpufreq driver falls under this category, but this driver was
invoking the _begin() and _end() APIs itself around frequency transitions,
which led to double invocation of the _begin() API. The _begin API makes
contending callers wait until the previous invocation is complete. Hence,
the powernow-k7 driver ended up waiting on itself, leading to system hangs
during boot.
Fix this by removing the calls to the _begin() and _end() APIs from the
powernow-k7 driver, since they rightly belong to the cpufreq core.
Signed-off-by: Srivatsa S. Bhat <srivatsa.b...@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.ku...@linaro.org>
---
drivers/cpufreq/powernow-k7.c | 4 ----
1 file changed, 4 deletions(-)
diff --git a/drivers/cpufreq/powernow-k7.c b/drivers/cpufreq/powernow-k7.c
index f911645..e61e224 100644
--- a/drivers/cpufreq/powernow-k7.c
+++ b/drivers/cpufreq/powernow-k7.c
@@ -269,8 +269,6 @@ static int powernow_target(struct cpufreq_policy *policy,
unsigned int index)
freqs.new = powernow_table[index].frequency;
- cpufreq_freq_transition_begin(policy, &freqs);
-
/* Now do the magic poking into the MSRs. */
if (have_a0 == 1) /* A0 errata 5 */
@@ -290,8 +288,6 @@ static int powernow_target(struct cpufreq_policy *policy,
unsigned int index)
if (have_a0 == 1)
local_irq_enable();
- cpufreq_freq_transition_end(policy, &freqs, 0);
-
return 0;
}
--
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