RE: [PATCH v2 1/8] cxl: Add helper function to retrieve a feature entry

[Shiju Jose <shiju.jose@huawei.com>]

>-----Original Message-----
>From: Dan Williams <dan.j.williams@intel.com>
>Sent: 26 March 2025 21:33
>To: Shiju Jose <shiju.jose@huawei.com>; linux-cxl@vger.kernel.org;
>dan.j.williams@intel.com; dave@stgolabs.net; Jonathan Cameron
><jonathan.cameron@huawei.com>; dave.jiang@intel.com;
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>nifan.cxl@gmail.com; tanxiaofei <tanxiaofei@huawei.com>; Zengtao (B)
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>Linuxarm <linuxarm@huawei.com>; Shiju Jose <shiju.jose@huawei.com>
>Subject: Re: [PATCH v2 1/8] cxl: Add helper function to retrieve a feature entry
>
>shiju.jose@ wrote:
>> From: Shiju Jose <shiju.jose@huawei.com>
>>
>> Add helper function to retrieve a feature entry from the supported
>> features list, if supported.
>>
>> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>> Reviewed-by: Fan Ni <fan.ni@samsung.com>
>> Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
>> ---
>>  drivers/cxl/core/core.h     |  2 ++
>>  drivers/cxl/core/features.c | 23 +++++++++++++++++++++++
>>  2 files changed, 25 insertions(+)
>>
>> diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h index
>> 1803aedb25ca..16bc717376fc 100644
>> --- a/drivers/cxl/core/core.h
>> +++ b/drivers/cxl/core/core.h
>> @@ -123,6 +123,8 @@ int cxl_ras_init(void);  void cxl_ras_exit(void);
>>
>>  #ifdef CONFIG_CXL_FEATURES
>> +struct cxl_feat_entry *cxl_get_feature_entry(struct cxl_dev_state *cxlds,
>> +					     const uuid_t *feat_uuid);
>
>It is unfortunate that this naming choice is too similar to cxl_get_feature().
>However, as I go to suggest a new name I find that this is a duplicate of
>get_support_feature_info() in Dave's fwctl series. Just drop this patch in favor of
>that.

Hi Dan,

I am fine to use get_support_feature_info() for the EDAC features. 
However this function is defined as static in the fwctl series and 
takes struct fwctl_rpc_cxl * as input for RPC instead of  uuid_t *
as in cxl_get_feature_entry().

static struct cxl_feat_entry *
get_support_feature_info(struct cxl_features_state *cxlfs,
			 const struct fwctl_rpc_cxl *rpc_in)

Can you suggest how to use get_support_feature_info() from within the CXL driver 
to retrieve a supported feature entry (for e.g an EDAC feature)?

>

Thanks,
Shiju