On 29 October 2018 at 19:10, Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> wrote:
> On 26/10/2018 16:48, Ulf Hansson wrote:
>> There's no point to register the cpuidle driver for the current CPU, when
>> the initialization of the arch specific back-end data fails by returning
>> -ENXIO.
>>
>> Instead, let's re-order the sequence to its original flow, by first trying
>> to initialize the back-end part and then act accordingly on the returned
>> error code. Additionally, let's print the error message, no matter of what
>> error code that was returned.
>>
>> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>> ---
>>
>> Note, as far as I can tell it's only qcom-spm that may return -ENXIO, which also
>> was original reason to why this error path was invented.
>>
>> Unfurtunate I don't have a qcom spm platfrom at hand, however I manually tried
>> this by hacking the PSCI driver to return -ENXIO for some CPUs. So I assume it
>> should then also work for qcom spm.
>>
>> ---
>> drivers/cpuidle/cpuidle-arm.c | 22 ++++++++++------------
>> 1 file changed, 10 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/cpuidle/cpuidle-arm.c b/drivers/cpuidle/cpuidle-arm.c
>> index 073557f433eb..df564d783216 100644
>> --- a/drivers/cpuidle/cpuidle-arm.c
>> +++ b/drivers/cpuidle/cpuidle-arm.c
>> @@ -103,13 +103,6 @@ static int __init arm_idle_init_cpu(int cpu)
>> goto out_kfree_drv;
>> }
>>
>> - ret = cpuidle_register_driver(drv);
>> - if (ret) {
>> - if (ret != -EBUSY)
>> - pr_err("Failed to register cpuidle driver\n");
>> - goto out_kfree_drv;
>> - }
>> -
>
> Why not move the following block at the beginning of the function ?
That's kind of what is happening in patch 2/2.
However, I wanted to take small steps, isolating one change per patch.
Does it make sense to keep $subject patch as is, when you look at
patch2/2?
>
> --->
>
> /*
> * Call arch CPU operations in order to initialize
> * idle states suspend back-end specific data
> */
> ret = arm_cpuidle_init(cpu);
>
> /*
> * Skip the cpuidle device initialization if the reported
> * failure is a HW misconfiguration/breakage (-ENXIO).
> */
> if (ret == -ENXIO)
> return 0;
>
> if (ret) {
> pr_err("CPU %d failed to init idle CPU ops\n", cpu);
> s/goto out_unregister_drv;/return ret;/
> }
>
> <---
[...]
Kind regards
Uffe
