Message ID | 20230330141314.1364083-1-wyes.karny@amd.com (mailing list archive) |
---|---|
State | Mainlined, archived |
Headers | show |
Series | amd-pstate: Fix amd_pstate mode switch | expand |
On Thu, Mar 30, 2023 at 4:13 PM Wyes Karny <wyes.karny@amd.com> wrote: > > amd_pstate mode can be changed by writing the mode name to the `status` > sysfs. But some combinations are not working. Fix this issue by taking > care of the edge cases. > > Before the fix the mode change combination test fails: > > #./pst_test.sh > Test passed: from: disable, to > Test passed: from: disable, to disable > Test failed: 1, From mode: disable, to mode: passive > Test failed: 1, From mode: disable, to mode: active > Test failed: 1, From mode: passive, to mode: active > Test passed: from: passive, to disable > Test failed: 1, From mode: passive, to mode: passive > Test failed: 1, From mode: passive, to mode: active > Test failed: 1, From mode: active, to mode: active > Test passed: from: active, to disable > Test failed: 1, From mode: active, to mode: passive > Test failed: 1, From mode: active, to mode: active > > After the fix test passes: > > #./pst_test.sh > Test passed: from: disable, to > Test passed: from: disable, to disable > Test passed: from: disable, to passive > Test passed: from: disable, to active > Test passed: from: passive, to active > Test passed: from: passive, to disable > Test passed: from: passive, to passive > Test passed: from: passive, to active > Test passed: from: active, to active > Test passed: from: active, to disable > Test passed: from: active, to passive > Test passed: from: active, to active > > Fixes: abd61c08ef349 ("cpufreq: amd-pstate: add driver working mode switch support") > > Acked-by: Huang Rui <ray.huang@amd.com> > Reviewed-by: Alexey Kardashevskiy <aik@amd.com> > Signed-off-by: Wyes Karny <wyes.karny@amd.com> > > Cc: "Rafael J. Wysocki" <rafael@kernel.org> > Cc: Viresh Kumar <viresh.kumar@linaro.org> > Cc: Mario Limonciello <mario.limonciello@amd.com> > Cc: Perry Yuan <Perry.Yuan@amd.com> This is all fine, but you need to tell me how it interacts with the amd-pstate changes in linux-next. Does it affect the code in linux-next at all or is it only for 6.3-rc? > --- > drivers/cpufreq/amd-pstate.c | 18 ++++++++---------- > 1 file changed, 8 insertions(+), 10 deletions(-) > > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c > index 73c7643b2697..8dd46fad151e 100644 > --- a/drivers/cpufreq/amd-pstate.c > +++ b/drivers/cpufreq/amd-pstate.c > @@ -840,22 +840,20 @@ static int amd_pstate_update_status(const char *buf, size_t size) > > switch(mode_idx) { > case AMD_PSTATE_DISABLE: > - if (!current_pstate_driver) > - return -EINVAL; > - if (cppc_state == AMD_PSTATE_ACTIVE) > - return -EBUSY; > - cpufreq_unregister_driver(current_pstate_driver); > - amd_pstate_driver_cleanup(); > + if (current_pstate_driver) { > + cpufreq_unregister_driver(current_pstate_driver); > + amd_pstate_driver_cleanup(); > + } > break; > case AMD_PSTATE_PASSIVE: > if (current_pstate_driver) { > if (current_pstate_driver == &amd_pstate_driver) > return 0; > cpufreq_unregister_driver(current_pstate_driver); > - cppc_state = AMD_PSTATE_PASSIVE; > - current_pstate_driver = &amd_pstate_driver; > } > > + current_pstate_driver = &amd_pstate_driver; > + cppc_state = AMD_PSTATE_PASSIVE; > ret = cpufreq_register_driver(current_pstate_driver); > break; > case AMD_PSTATE_ACTIVE: > @@ -863,10 +861,10 @@ static int amd_pstate_update_status(const char *buf, size_t size) > if (current_pstate_driver == &amd_pstate_epp_driver) > return 0; > cpufreq_unregister_driver(current_pstate_driver); > - current_pstate_driver = &amd_pstate_epp_driver; > - cppc_state = AMD_PSTATE_ACTIVE; > } > > + current_pstate_driver = &amd_pstate_epp_driver; > + cppc_state = AMD_PSTATE_ACTIVE; > ret = cpufreq_register_driver(current_pstate_driver); > break; > default: > -- > 2.34.1 >
Hi Rafael, On 30 Mar 20:19, Rafael J. Wysocki wrote: > On Thu, Mar 30, 2023 at 4:13 PM Wyes Karny <wyes.karny@amd.com> wrote: > > > > amd_pstate mode can be changed by writing the mode name to the `status` > > sysfs. But some combinations are not working. Fix this issue by taking > > care of the edge cases. > > > > Before the fix the mode change combination test fails: > > > > #./pst_test.sh > > Test passed: from: disable, to > > Test passed: from: disable, to disable > > Test failed: 1, From mode: disable, to mode: passive > > Test failed: 1, From mode: disable, to mode: active > > Test failed: 1, From mode: passive, to mode: active > > Test passed: from: passive, to disable > > Test failed: 1, From mode: passive, to mode: passive > > Test failed: 1, From mode: passive, to mode: active > > Test failed: 1, From mode: active, to mode: active > > Test passed: from: active, to disable > > Test failed: 1, From mode: active, to mode: passive > > Test failed: 1, From mode: active, to mode: active > > > > After the fix test passes: > > > > #./pst_test.sh > > Test passed: from: disable, to > > Test passed: from: disable, to disable > > Test passed: from: disable, to passive > > Test passed: from: disable, to active > > Test passed: from: passive, to active > > Test passed: from: passive, to disable > > Test passed: from: passive, to passive > > Test passed: from: passive, to active > > Test passed: from: active, to active > > Test passed: from: active, to disable > > Test passed: from: active, to passive > > Test passed: from: active, to active > > > > Fixes: abd61c08ef349 ("cpufreq: amd-pstate: add driver working mode switch support") > > > > Acked-by: Huang Rui <ray.huang@amd.com> > > Reviewed-by: Alexey Kardashevskiy <aik@amd.com> > > Signed-off-by: Wyes Karny <wyes.karny@amd.com> > > > > Cc: "Rafael J. Wysocki" <rafael@kernel.org> > > Cc: Viresh Kumar <viresh.kumar@linaro.org> > > Cc: Mario Limonciello <mario.limonciello@amd.com> > > Cc: Perry Yuan <Perry.Yuan@amd.com> > > This is all fine, but you need to tell me how it interacts with the > amd-pstate changes in linux-next. > > Does it affect the code in linux-next at all or is it only for 6.3-rc? > This is only for 6.3-rc. The commit 3ca7bc818d8c ("cpufreq: amd-pstate: Add guided mode control support via sysfs") in linux-next may not apply cleanly after this fix. Please let me know if I need to rebase and send the guided mode patches [1]. [1]: https://lore.kernel.org/linux-pm/20230307112740.132338-1-wyes.karny@amd.com/ Thanks, Wyes > > --- > > drivers/cpufreq/amd-pstate.c | 18 ++++++++---------- > > 1 file changed, 8 insertions(+), 10 deletions(-) > > > > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c > > index 73c7643b2697..8dd46fad151e 100644 > > --- a/drivers/cpufreq/amd-pstate.c > > +++ b/drivers/cpufreq/amd-pstate.c > > @@ -840,22 +840,20 @@ static int amd_pstate_update_status(const char *buf, size_t size) > > > > switch(mode_idx) { > > case AMD_PSTATE_DISABLE: > > - if (!current_pstate_driver) > > - return -EINVAL; > > - if (cppc_state == AMD_PSTATE_ACTIVE) > > - return -EBUSY; > > - cpufreq_unregister_driver(current_pstate_driver); > > - amd_pstate_driver_cleanup(); > > + if (current_pstate_driver) { > > + cpufreq_unregister_driver(current_pstate_driver); > > + amd_pstate_driver_cleanup(); > > + } > > break; > > case AMD_PSTATE_PASSIVE: > > if (current_pstate_driver) { > > if (current_pstate_driver == &amd_pstate_driver) > > return 0; > > cpufreq_unregister_driver(current_pstate_driver); > > - cppc_state = AMD_PSTATE_PASSIVE; > > - current_pstate_driver = &amd_pstate_driver; > > } > > > > + current_pstate_driver = &amd_pstate_driver; > > + cppc_state = AMD_PSTATE_PASSIVE; > > ret = cpufreq_register_driver(current_pstate_driver); > > break; > > case AMD_PSTATE_ACTIVE: > > @@ -863,10 +861,10 @@ static int amd_pstate_update_status(const char *buf, size_t size) > > if (current_pstate_driver == &amd_pstate_epp_driver) > > return 0; > > cpufreq_unregister_driver(current_pstate_driver); > > - current_pstate_driver = &amd_pstate_epp_driver; > > - cppc_state = AMD_PSTATE_ACTIVE; > > } > > > > + current_pstate_driver = &amd_pstate_epp_driver; > > + cppc_state = AMD_PSTATE_ACTIVE; > > ret = cpufreq_register_driver(current_pstate_driver); > > break; > > default: > > -- > > 2.34.1 > >
On Fri, Mar 31, 2023 at 8:12 AM Wyes Karny <wyes.karny@amd.com> wrote: > > Hi Rafael, > > On 30 Mar 20:19, Rafael J. Wysocki wrote: > > On Thu, Mar 30, 2023 at 4:13 PM Wyes Karny <wyes.karny@amd.com> wrote: > > > > > > amd_pstate mode can be changed by writing the mode name to the `status` > > > sysfs. But some combinations are not working. Fix this issue by taking > > > care of the edge cases. > > > > > > Before the fix the mode change combination test fails: > > > > > > #./pst_test.sh > > > Test passed: from: disable, to > > > Test passed: from: disable, to disable > > > Test failed: 1, From mode: disable, to mode: passive > > > Test failed: 1, From mode: disable, to mode: active > > > Test failed: 1, From mode: passive, to mode: active > > > Test passed: from: passive, to disable > > > Test failed: 1, From mode: passive, to mode: passive > > > Test failed: 1, From mode: passive, to mode: active > > > Test failed: 1, From mode: active, to mode: active > > > Test passed: from: active, to disable > > > Test failed: 1, From mode: active, to mode: passive > > > Test failed: 1, From mode: active, to mode: active > > > > > > After the fix test passes: > > > > > > #./pst_test.sh > > > Test passed: from: disable, to > > > Test passed: from: disable, to disable > > > Test passed: from: disable, to passive > > > Test passed: from: disable, to active > > > Test passed: from: passive, to active > > > Test passed: from: passive, to disable > > > Test passed: from: passive, to passive > > > Test passed: from: passive, to active > > > Test passed: from: active, to active > > > Test passed: from: active, to disable > > > Test passed: from: active, to passive > > > Test passed: from: active, to active > > > > > > Fixes: abd61c08ef349 ("cpufreq: amd-pstate: add driver working mode switch support") > > > > > > Acked-by: Huang Rui <ray.huang@amd.com> > > > Reviewed-by: Alexey Kardashevskiy <aik@amd.com> > > > Signed-off-by: Wyes Karny <wyes.karny@amd.com> > > > > > > Cc: "Rafael J. Wysocki" <rafael@kernel.org> > > > Cc: Viresh Kumar <viresh.kumar@linaro.org> > > > Cc: Mario Limonciello <mario.limonciello@amd.com> > > > Cc: Perry Yuan <Perry.Yuan@amd.com> > > > > This is all fine, but you need to tell me how it interacts with the > > amd-pstate changes in linux-next. > > > > Does it affect the code in linux-next at all or is it only for 6.3-rc? > > > > This is only for 6.3-rc. > The commit 3ca7bc818d8c ("cpufreq: amd-pstate: Add guided mode control > support via sysfs") in linux-next may not apply cleanly after this fix. > Please let me know if I need to rebase and send the guided mode patches [1]. > > [1]: https://lore.kernel.org/linux-pm/20230307112740.132338-1-wyes.karny@amd.com/ Well, instead, you please let me know how to resolve the merge conflict between the patch below and your series. Can I simply assume that the code added by commit 3ca7bc818d8c replaces the code modified by the $subject patch? > > > --- > > > drivers/cpufreq/amd-pstate.c | 18 ++++++++---------- > > > 1 file changed, 8 insertions(+), 10 deletions(-) > > > > > > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c > > > index 73c7643b2697..8dd46fad151e 100644 > > > --- a/drivers/cpufreq/amd-pstate.c > > > +++ b/drivers/cpufreq/amd-pstate.c > > > @@ -840,22 +840,20 @@ static int amd_pstate_update_status(const char *buf, size_t size) > > > > > > switch(mode_idx) { > > > case AMD_PSTATE_DISABLE: > > > - if (!current_pstate_driver) > > > - return -EINVAL; > > > - if (cppc_state == AMD_PSTATE_ACTIVE) > > > - return -EBUSY; > > > - cpufreq_unregister_driver(current_pstate_driver); > > > - amd_pstate_driver_cleanup(); > > > + if (current_pstate_driver) { > > > + cpufreq_unregister_driver(current_pstate_driver); > > > + amd_pstate_driver_cleanup(); > > > + } > > > break; > > > case AMD_PSTATE_PASSIVE: > > > if (current_pstate_driver) { > > > if (current_pstate_driver == &amd_pstate_driver) > > > return 0; > > > cpufreq_unregister_driver(current_pstate_driver); > > > - cppc_state = AMD_PSTATE_PASSIVE; > > > - current_pstate_driver = &amd_pstate_driver; > > > } > > > > > > + current_pstate_driver = &amd_pstate_driver; > > > + cppc_state = AMD_PSTATE_PASSIVE; > > > ret = cpufreq_register_driver(current_pstate_driver); > > > break; > > > case AMD_PSTATE_ACTIVE: > > > @@ -863,10 +861,10 @@ static int amd_pstate_update_status(const char *buf, size_t size) > > > if (current_pstate_driver == &amd_pstate_epp_driver) > > > return 0; > > > cpufreq_unregister_driver(current_pstate_driver); > > > - current_pstate_driver = &amd_pstate_epp_driver; > > > - cppc_state = AMD_PSTATE_ACTIVE; > > > } > > > > > > + current_pstate_driver = &amd_pstate_epp_driver; > > > + cppc_state = AMD_PSTATE_ACTIVE; > > > ret = cpufreq_register_driver(current_pstate_driver); > > > break; > > > default: > > > -- > > > 2.34.1 > > >
On 31 Mar 11:11, Rafael J. Wysocki wrote: > On Fri, Mar 31, 2023 at 8:12 AM Wyes Karny <wyes.karny@amd.com> wrote: > > > > Hi Rafael, > > > > On 30 Mar 20:19, Rafael J. Wysocki wrote: > > > On Thu, Mar 30, 2023 at 4:13 PM Wyes Karny <wyes.karny@amd.com> wrote: > > > > > > > > amd_pstate mode can be changed by writing the mode name to the `status` > > > > sysfs. But some combinations are not working. Fix this issue by taking > > > > care of the edge cases. > > > > > > > > Before the fix the mode change combination test fails: > > > > > > > > #./pst_test.sh > > > > Test passed: from: disable, to > > > > Test passed: from: disable, to disable > > > > Test failed: 1, From mode: disable, to mode: passive > > > > Test failed: 1, From mode: disable, to mode: active > > > > Test failed: 1, From mode: passive, to mode: active > > > > Test passed: from: passive, to disable > > > > Test failed: 1, From mode: passive, to mode: passive > > > > Test failed: 1, From mode: passive, to mode: active > > > > Test failed: 1, From mode: active, to mode: active > > > > Test passed: from: active, to disable > > > > Test failed: 1, From mode: active, to mode: passive > > > > Test failed: 1, From mode: active, to mode: active > > > > > > > > After the fix test passes: > > > > > > > > #./pst_test.sh > > > > Test passed: from: disable, to > > > > Test passed: from: disable, to disable > > > > Test passed: from: disable, to passive > > > > Test passed: from: disable, to active > > > > Test passed: from: passive, to active > > > > Test passed: from: passive, to disable > > > > Test passed: from: passive, to passive > > > > Test passed: from: passive, to active > > > > Test passed: from: active, to active > > > > Test passed: from: active, to disable > > > > Test passed: from: active, to passive > > > > Test passed: from: active, to active > > > > > > > > Fixes: abd61c08ef349 ("cpufreq: amd-pstate: add driver working mode switch support") > > > > > > > > Acked-by: Huang Rui <ray.huang@amd.com> > > > > Reviewed-by: Alexey Kardashevskiy <aik@amd.com> > > > > Signed-off-by: Wyes Karny <wyes.karny@amd.com> > > > > > > > > Cc: "Rafael J. Wysocki" <rafael@kernel.org> > > > > Cc: Viresh Kumar <viresh.kumar@linaro.org> > > > > Cc: Mario Limonciello <mario.limonciello@amd.com> > > > > Cc: Perry Yuan <Perry.Yuan@amd.com> > > > > > > This is all fine, but you need to tell me how it interacts with the > > > amd-pstate changes in linux-next. > > > > > > Does it affect the code in linux-next at all or is it only for 6.3-rc? > > > > > > > This is only for 6.3-rc. > > The commit 3ca7bc818d8c ("cpufreq: amd-pstate: Add guided mode control > > support via sysfs") in linux-next may not apply cleanly after this fix. > > Please let me know if I need to rebase and send the guided mode patches [1]. > > > > [1]: https://lore.kernel.org/linux-pm/20230307112740.132338-1-wyes.karny@amd.com/ > > Well, instead, you please let me know how to resolve the merge > conflict between the patch below and your series. > > Can I simply assume that the code added by commit 3ca7bc818d8c > replaces the code modified by the $subject patch? Yes, commit 3ca7bc818d8c replaces the whole `amd_pstate_update_status` function with new implementation. > > > > > --- > > > > drivers/cpufreq/amd-pstate.c | 18 ++++++++---------- > > > > 1 file changed, 8 insertions(+), 10 deletions(-) > > > > > > > > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c > > > > index 73c7643b2697..8dd46fad151e 100644 > > > > --- a/drivers/cpufreq/amd-pstate.c > > > > +++ b/drivers/cpufreq/amd-pstate.c > > > > @@ -840,22 +840,20 @@ static int amd_pstate_update_status(const char *buf, size_t size) > > > > > > > > switch(mode_idx) { > > > > case AMD_PSTATE_DISABLE: > > > > - if (!current_pstate_driver) > > > > - return -EINVAL; > > > > - if (cppc_state == AMD_PSTATE_ACTIVE) > > > > - return -EBUSY; > > > > - cpufreq_unregister_driver(current_pstate_driver); > > > > - amd_pstate_driver_cleanup(); > > > > + if (current_pstate_driver) { > > > > + cpufreq_unregister_driver(current_pstate_driver); > > > > + amd_pstate_driver_cleanup(); > > > > + } > > > > break; > > > > case AMD_PSTATE_PASSIVE: > > > > if (current_pstate_driver) { > > > > if (current_pstate_driver == &amd_pstate_driver) > > > > return 0; > > > > cpufreq_unregister_driver(current_pstate_driver); > > > > - cppc_state = AMD_PSTATE_PASSIVE; > > > > - current_pstate_driver = &amd_pstate_driver; > > > > } > > > > > > > > + current_pstate_driver = &amd_pstate_driver; > > > > + cppc_state = AMD_PSTATE_PASSIVE; > > > > ret = cpufreq_register_driver(current_pstate_driver); > > > > break; > > > > case AMD_PSTATE_ACTIVE: > > > > @@ -863,10 +861,10 @@ static int amd_pstate_update_status(const char *buf, size_t size) > > > > if (current_pstate_driver == &amd_pstate_epp_driver) > > > > return 0; > > > > cpufreq_unregister_driver(current_pstate_driver); > > > > - current_pstate_driver = &amd_pstate_epp_driver; > > > > - cppc_state = AMD_PSTATE_ACTIVE; > > > > } > > > > > > > > + current_pstate_driver = &amd_pstate_epp_driver; > > > > + cppc_state = AMD_PSTATE_ACTIVE; > > > > ret = cpufreq_register_driver(current_pstate_driver); > > > > break; > > > > default: > > > > -- > > > > 2.34.1 > > > >
On Fri, Mar 31, 2023 at 12:18 PM Wyes Karny <wyes.karny@amd.com> wrote: > > On 31 Mar 11:11, Rafael J. Wysocki wrote: > > On Fri, Mar 31, 2023 at 8:12 AM Wyes Karny <wyes.karny@amd.com> wrote: > > > > > > Hi Rafael, > > > > > > On 30 Mar 20:19, Rafael J. Wysocki wrote: > > > > On Thu, Mar 30, 2023 at 4:13 PM Wyes Karny <wyes.karny@amd.com> wrote: > > > > > > > > > > amd_pstate mode can be changed by writing the mode name to the `status` > > > > > sysfs. But some combinations are not working. Fix this issue by taking > > > > > care of the edge cases. > > > > > > > > > > Before the fix the mode change combination test fails: > > > > > > > > > > #./pst_test.sh > > > > > Test passed: from: disable, to > > > > > Test passed: from: disable, to disable > > > > > Test failed: 1, From mode: disable, to mode: passive > > > > > Test failed: 1, From mode: disable, to mode: active > > > > > Test failed: 1, From mode: passive, to mode: active > > > > > Test passed: from: passive, to disable > > > > > Test failed: 1, From mode: passive, to mode: passive > > > > > Test failed: 1, From mode: passive, to mode: active > > > > > Test failed: 1, From mode: active, to mode: active > > > > > Test passed: from: active, to disable > > > > > Test failed: 1, From mode: active, to mode: passive > > > > > Test failed: 1, From mode: active, to mode: active > > > > > > > > > > After the fix test passes: > > > > > > > > > > #./pst_test.sh > > > > > Test passed: from: disable, to > > > > > Test passed: from: disable, to disable > > > > > Test passed: from: disable, to passive > > > > > Test passed: from: disable, to active > > > > > Test passed: from: passive, to active > > > > > Test passed: from: passive, to disable > > > > > Test passed: from: passive, to passive > > > > > Test passed: from: passive, to active > > > > > Test passed: from: active, to active > > > > > Test passed: from: active, to disable > > > > > Test passed: from: active, to passive > > > > > Test passed: from: active, to active > > > > > > > > > > Fixes: abd61c08ef349 ("cpufreq: amd-pstate: add driver working mode switch support") > > > > > > > > > > Acked-by: Huang Rui <ray.huang@amd.com> > > > > > Reviewed-by: Alexey Kardashevskiy <aik@amd.com> > > > > > Signed-off-by: Wyes Karny <wyes.karny@amd.com> > > > > > > > > > > Cc: "Rafael J. Wysocki" <rafael@kernel.org> > > > > > Cc: Viresh Kumar <viresh.kumar@linaro.org> > > > > > Cc: Mario Limonciello <mario.limonciello@amd.com> > > > > > Cc: Perry Yuan <Perry.Yuan@amd.com> > > > > > > > > This is all fine, but you need to tell me how it interacts with the > > > > amd-pstate changes in linux-next. > > > > > > > > Does it affect the code in linux-next at all or is it only for 6.3-rc? > > > > > > > > > > This is only for 6.3-rc. > > > The commit 3ca7bc818d8c ("cpufreq: amd-pstate: Add guided mode control > > > support via sysfs") in linux-next may not apply cleanly after this fix. > > > Please let me know if I need to rebase and send the guided mode patches [1]. > > > > > > [1]: https://lore.kernel.org/linux-pm/20230307112740.132338-1-wyes.karny@amd.com/ > > > > Well, instead, you please let me know how to resolve the merge > > conflict between the patch below and your series. > > > > Can I simply assume that the code added by commit 3ca7bc818d8c > > replaces the code modified by the $subject patch? > > Yes, commit 3ca7bc818d8c replaces the whole `amd_pstate_update_status` > function with new implementation. OK, thanks! $subject patch has been queued up for 6.3-rc7, thanks!
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 73c7643b2697..8dd46fad151e 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -840,22 +840,20 @@ static int amd_pstate_update_status(const char *buf, size_t size) switch(mode_idx) { case AMD_PSTATE_DISABLE: - if (!current_pstate_driver) - return -EINVAL; - if (cppc_state == AMD_PSTATE_ACTIVE) - return -EBUSY; - cpufreq_unregister_driver(current_pstate_driver); - amd_pstate_driver_cleanup(); + if (current_pstate_driver) { + cpufreq_unregister_driver(current_pstate_driver); + amd_pstate_driver_cleanup(); + } break; case AMD_PSTATE_PASSIVE: if (current_pstate_driver) { if (current_pstate_driver == &amd_pstate_driver) return 0; cpufreq_unregister_driver(current_pstate_driver); - cppc_state = AMD_PSTATE_PASSIVE; - current_pstate_driver = &amd_pstate_driver; } + current_pstate_driver = &amd_pstate_driver; + cppc_state = AMD_PSTATE_PASSIVE; ret = cpufreq_register_driver(current_pstate_driver); break; case AMD_PSTATE_ACTIVE: @@ -863,10 +861,10 @@ static int amd_pstate_update_status(const char *buf, size_t size) if (current_pstate_driver == &amd_pstate_epp_driver) return 0; cpufreq_unregister_driver(current_pstate_driver); - current_pstate_driver = &amd_pstate_epp_driver; - cppc_state = AMD_PSTATE_ACTIVE; } + current_pstate_driver = &amd_pstate_epp_driver; + cppc_state = AMD_PSTATE_ACTIVE; ret = cpufreq_register_driver(current_pstate_driver); break; default: