diff options
author | Srivatsa S. Bhat | 2014-04-28 13:54:58 -0500 |
---|---|---|
committer | Rafael J. Wysocki | 2014-04-28 18:22:54 -0500 |
commit | 8997b185119966c62c6e95e7b010b4060407e358 (patch) | |
tree | 2085f1f7ca82fdb9d143f2d135929e4eb074fb3c /drivers | |
parent | 3221e55b72359c44ed75afbcf707710af5bc2d59 (diff) | |
download | linux-phy-8997b185119966c62c6e95e7b010b4060407e358.tar.gz linux-phy-8997b185119966c62c6e95e7b010b4060407e358.tar.xz linux-phy-8997b185119966c62c6e95e7b010b4060407e358.zip |
cpufreq: powernow-k7: Fix double invocation of cpufreq_freq_transition_begin/end
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.
Fixes: 12478cf0c55e (cpufreq: Make sure frequency transitions are serialized)
Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/cpufreq/powernow-k7.c | 4 |
1 files changed, 0 insertions, 4 deletions
diff --git a/drivers/cpufreq/powernow-k7.c b/drivers/cpufreq/powernow-k7.c index f911645c3f6d..e61e224475ad 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) | |||
269 | 269 | ||
270 | freqs.new = powernow_table[index].frequency; | 270 | freqs.new = powernow_table[index].frequency; |
271 | 271 | ||
272 | cpufreq_freq_transition_begin(policy, &freqs); | ||
273 | |||
274 | /* Now do the magic poking into the MSRs. */ | 272 | /* Now do the magic poking into the MSRs. */ |
275 | 273 | ||
276 | if (have_a0 == 1) /* A0 errata 5 */ | 274 | if (have_a0 == 1) /* A0 errata 5 */ |
@@ -290,8 +288,6 @@ static int powernow_target(struct cpufreq_policy *policy, unsigned int index) | |||
290 | if (have_a0 == 1) | 288 | if (have_a0 == 1) |
291 | local_irq_enable(); | 289 | local_irq_enable(); |
292 | 290 | ||
293 | cpufreq_freq_transition_end(policy, &freqs, 0); | ||
294 | |||
295 | return 0; | 291 | return 0; |
296 | } | 292 | } |
297 | 293 | ||