Re: [PATCH] ACPI: nfit: adjust annotation for why return 0 if fail to find NFIT at startup

From: Dave Jiang
Date: Tue Aug 07 2018 - 18:46:47 EST




On 08/07/2018 12:25 PM, Verma, Vishal L wrote:
>
> On Tue, 2018-08-07 at 02:15 -0400, Ocean He wrote:
>> From: Ocean He <hehy1@xxxxxxxxxx>
>
> Just some minor nits in commit message wording:
>
>>
>> Add detail explanation why it's ok to return 0 if fail to find NFIT at
> detailed ^for ^we ^an
>> startup, refer to chapter 9.20.2 NVDIMM Root Device in ACPI 6.2 spec.
> . Refer
>
> Perhaps Dave can fixup while applying..

Applied and updated.

>>
>> Signed-off-by: Ocean He <hehy1@xxxxxxxxxx>
>> ---
>> v1: https://lists.01.org/pipermail/linux-nvdimm/2018-August/017311.html
>> v2: Per Vishal's comments of v1, it turns out that it's right to keep
>> "return 0" if NFIT not found at boot time. This v2 adjust annotation
>> to avoid misunderstanding of "return 0".
>
> Looks good, thanks for the update. Feel free to add:
> Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>
>
>>
>> drivers/acpi/nfit/core.c | 8 +++++++-
>> 1 file changed, 7 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
>> index 7c47900..1b982fe 100644
>> --- a/drivers/acpi/nfit/core.c
>> +++ b/drivers/acpi/nfit/core.c
>> @@ -3353,7 +3353,13 @@ static int acpi_nfit_add(struct acpi_device *adev)
>>
>> status = acpi_get_table(ACPI_SIG_NFIT, 0, &tbl);
>> if (ACPI_FAILURE(status)) {
>> - /* This is ok, we could have an nvdimm hotplugged later */
>> + /* The NVDIMM root device allows OS to trigger enumeration of
>> + * NVDIMMs through NFIT at boot time and re-enumeration at
>> + * root level via the _FIT method during runtime.
>> + * This is ok to return 0 here, we could have an nvdimm
>> + * hotplugged later and evaluate _FIT method which returns
>> + * data in the format of a series of NFIT Structures.
>> + */
>> dev_dbg(dev, "failed to find NFIT at startup\n");
>> return 0;
>> }