diff mbox series

[RFC,v9,05/11] cxl/mbox: Add GET_FEATURE mailbox command

Message ID 20240716150336.2042-6-shiju.jose@huawei.com (mailing list archive)
State RFC, archived
Headers show
Series EDAC: Scrub: Introduce generic EDAC RAS control feature driver + CXL/ACPI-RAS2 drivers | expand

Commit Message

Shiju Jose July 16, 2024, 3:03 p.m. UTC
From: Shiju Jose <shiju.jose@huawei.com>

Add support for GET_FEATURE mailbox command.

CXL spec 3.1 section 8.2.9.6 describes optional device specific features.
The settings of a feature can be retrieved using Get Feature command.

Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
---
 drivers/cxl/core/mbox.c | 37 +++++++++++++++++++++++++++++++++++++
 drivers/cxl/cxlmem.h    | 27 +++++++++++++++++++++++++++
 2 files changed, 64 insertions(+)

Comments

Fan Ni July 17, 2024, 6:08 p.m. UTC | #1
On Tue, Jul 16, 2024 at 04:03:29PM +0100, shiju.jose@huawei.com wrote:
> From: Shiju Jose <shiju.jose@huawei.com>
> 
> Add support for GET_FEATURE mailbox command.
> 
> CXL spec 3.1 section 8.2.9.6 describes optional device specific features.
> The settings of a feature can be retrieved using Get Feature command.
> 
> Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
> ---
Minor comments inline.

>  drivers/cxl/core/mbox.c | 37 +++++++++++++++++++++++++++++++++++++
>  drivers/cxl/cxlmem.h    | 27 +++++++++++++++++++++++++++
>  2 files changed, 64 insertions(+)
> 
> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
> index 9b9b1d26454e..b1eeed508459 100644
> --- a/drivers/cxl/core/mbox.c
> +++ b/drivers/cxl/core/mbox.c
> @@ -1351,6 +1351,43 @@ int cxl_get_supported_features(struct cxl_memdev_state *mds,
>  }
>  EXPORT_SYMBOL_NS_GPL(cxl_get_supported_features, CXL);
>  
> +size_t cxl_get_feature(struct cxl_memdev_state *mds,
> +		       const uuid_t feat_uuid, void *feat_out,
> +		       size_t feat_out_size,
> +		       enum cxl_get_feat_selection selection)
feat_uuid and selection are both payload inputs, maybe more natural to put
them together before feat_out.
> +{
> +	size_t data_to_rd_size, size_out;
> +	struct cxl_mbox_get_feat_in pi;
> +	struct cxl_mbox_cmd mbox_cmd;
> +	size_t data_rcvd_size = 0;
> +	int rc;
> +
> +	size_out = min(feat_out_size, mds->payload_size);
> +	pi.uuid = feat_uuid;
> +	pi.selection = selection;
> +	do {
> +		data_to_rd_size = min(feat_out_size - data_rcvd_size, mds->payload_size);
> +		pi.offset = cpu_to_le16(data_rcvd_size);
> +		pi.count = cpu_to_le16(data_to_rd_size);
> +
> +		mbox_cmd = (struct cxl_mbox_cmd) {
> +			.opcode = CXL_MBOX_OP_GET_FEATURE,
> +			.size_in = sizeof(pi),
> +			.payload_in = &pi,
> +			.size_out = size_out,
> +			.payload_out = feat_out + data_rcvd_size,
> +			.min_out = data_to_rd_size,
> +		};
> +		rc = cxl_internal_send_cmd(mds, &mbox_cmd);
> +		if (rc < 0 || mbox_cmd.size_out == 0)
Is there other case when size_out will be 0 other than the feat_out_size
is 0?

If feat_out_size is 0, maybe we return directly, or we use while () {},
instead of do {} while.
Anyway, if there is no other case that will return size_out as 0, we can
avoid the check.

Fan
> +			return 0;
> +		data_rcvd_size += mbox_cmd.size_out;
> +	} while (data_rcvd_size < feat_out_size);
> +
> +	return data_rcvd_size;
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_get_feature, CXL);
> +
>  int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
>  		       struct cxl_region *cxlr)
>  {
> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
> index b0e1565b9d2e..25698a6fbe66 100644
> --- a/drivers/cxl/cxlmem.h
> +++ b/drivers/cxl/cxlmem.h
> @@ -531,6 +531,7 @@ enum cxl_opcode {
>  	CXL_MBOX_OP_CLEAR_LOG           = 0x0403,
>  	CXL_MBOX_OP_GET_SUP_LOG_SUBLIST = 0x0405,
>  	CXL_MBOX_OP_GET_SUPPORTED_FEATURES	= 0x0500,
> +	CXL_MBOX_OP_GET_FEATURE		= 0x0501,
>  	CXL_MBOX_OP_IDENTIFY		= 0x4000,
>  	CXL_MBOX_OP_GET_PARTITION_INFO	= 0x4100,
>  	CXL_MBOX_OP_SET_PARTITION_INFO	= 0x4101,
> @@ -757,6 +758,28 @@ struct cxl_mbox_get_supp_feats_out {
>  	struct cxl_mbox_supp_feat_entry feat_entries[];
>  } __packed;
>  
> +/*
> + * Get Feature CXL 3.1 Spec 8.2.9.6.2
> + */
> +
> +/*
> + * Get Feature input payload
> + * CXL rev 3.1 section 8.2.9.6.2 Table 8-99
> + */
> +enum cxl_get_feat_selection {
> +	CXL_GET_FEAT_SEL_CURRENT_VALUE,
> +	CXL_GET_FEAT_SEL_DEFAULT_VALUE,
> +	CXL_GET_FEAT_SEL_SAVED_VALUE,
> +	CXL_GET_FEAT_SEL_MAX
> +};
> +
> +struct cxl_mbox_get_feat_in {
> +	uuid_t uuid;
> +	__le16 offset;
> +	__le16 count;
> +	u8 selection;
> +}  __packed;
> +
>  /* Get Poison List  CXL 3.0 Spec 8.2.9.8.4.1 */
>  struct cxl_mbox_poison_in {
>  	__le64 offset;
> @@ -891,6 +914,10 @@ int cxl_set_timestamp(struct cxl_memdev_state *mds);
>  int cxl_get_supported_features(struct cxl_memdev_state *mds,
>  			       u32 count, u16 start_index,
>  			       struct cxl_mbox_get_supp_feats_out *feats_out);
> +size_t cxl_get_feature(struct cxl_memdev_state *mds,
> +		       const uuid_t feat_uuid, void *feat_out,
> +		       size_t feat_out_size,
> +		       enum cxl_get_feat_selection selection);
>  int cxl_poison_state_init(struct cxl_memdev_state *mds);
>  int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
>  		       struct cxl_region *cxlr);
> -- 
> 2.34.1
>
Shiju Jose July 18, 2024, 9:11 a.m. UTC | #2
>-----Original Message-----
>From: nifan.cxl@gmail.com <nifan.cxl@gmail.com>
>Sent: 17 July 2024 19:08
>To: Shiju Jose <shiju.jose@huawei.com>
>Cc: linux-edac@vger.kernel.org; linux-cxl@vger.kernel.org; linux-
>acpi@vger.kernel.org; linux-mm@kvack.org; linux-kernel@vger.kernel.org;
>bp@alien8.de; tony.luck@intel.com; rafael@kernel.org; lenb@kernel.org;
>mchehab@kernel.org; dan.j.williams@intel.com; dave@stgolabs.net; Jonathan
>Cameron <jonathan.cameron@huawei.com>; dave.jiang@intel.com;
>alison.schofield@intel.com; vishal.l.verma@intel.com; ira.weiny@intel.com;
>david@redhat.com; Vilas.Sridharan@amd.com; leo.duran@amd.com;
>Yazen.Ghannam@amd.com; rientjes@google.com; jiaqiyan@google.com;
>Jon.Grimm@amd.com; dave.hansen@linux.intel.com;
>naoya.horiguchi@nec.com; james.morse@arm.com; jthoughton@google.com;
>somasundaram.a@hpe.com; erdemaktas@google.com; pgonda@google.com;
>duenwen@google.com; mike.malvestuto@intel.com; gthelen@google.com;
>wschwartz@amperecomputing.com; dferguson@amperecomputing.com;
>wbs@os.amperecomputing.com; nifan.cxl@gmail.com; tanxiaofei
><tanxiaofei@huawei.com>; Zengtao (B) <prime.zeng@hisilicon.com>; Roberto
>Sassu <roberto.sassu@huawei.com>; kangkang.shen@futurewei.com;
>wanghuiqiang <wanghuiqiang@huawei.com>; Linuxarm
><linuxarm@huawei.com>
>Subject: Re: [RFC PATCH v9 05/11] cxl/mbox: Add GET_FEATURE mailbox
>command
>
>On Tue, Jul 16, 2024 at 04:03:29PM +0100, shiju.jose@huawei.com wrote:
>> From: Shiju Jose <shiju.jose@huawei.com>
>>
>> Add support for GET_FEATURE mailbox command.
>>
>> CXL spec 3.1 section 8.2.9.6 describes optional device specific features.
>> The settings of a feature can be retrieved using Get Feature command.
>>
>> Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
>> ---
>Minor comments inline.
>
>>  drivers/cxl/core/mbox.c | 37 +++++++++++++++++++++++++++++++++++++
>>  drivers/cxl/cxlmem.h    | 27 +++++++++++++++++++++++++++
>>  2 files changed, 64 insertions(+)
>>
>> diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c index
>> 9b9b1d26454e..b1eeed508459 100644
>> --- a/drivers/cxl/core/mbox.c
>> +++ b/drivers/cxl/core/mbox.c
>> @@ -1351,6 +1351,43 @@ int cxl_get_supported_features(struct
>> cxl_memdev_state *mds,  }
>> EXPORT_SYMBOL_NS_GPL(cxl_get_supported_features, CXL);
>>
>> +size_t cxl_get_feature(struct cxl_memdev_state *mds,
>> +		       const uuid_t feat_uuid, void *feat_out,
>> +		       size_t feat_out_size,
>> +		       enum cxl_get_feat_selection selection)
>feat_uuid and selection are both payload inputs, maybe more natural to put
>them together before feat_out.
Will do.
>> +{
>> +	size_t data_to_rd_size, size_out;
>> +	struct cxl_mbox_get_feat_in pi;
>> +	struct cxl_mbox_cmd mbox_cmd;
>> +	size_t data_rcvd_size = 0;
>> +	int rc;
>> +
>> +	size_out = min(feat_out_size, mds->payload_size);
>> +	pi.uuid = feat_uuid;
>> +	pi.selection = selection;
>> +	do {
>> +		data_to_rd_size = min(feat_out_size - data_rcvd_size, mds-
>>payload_size);
>> +		pi.offset = cpu_to_le16(data_rcvd_size);
>> +		pi.count = cpu_to_le16(data_to_rd_size);
>> +
>> +		mbox_cmd = (struct cxl_mbox_cmd) {
>> +			.opcode = CXL_MBOX_OP_GET_FEATURE,
>> +			.size_in = sizeof(pi),
>> +			.payload_in = &pi,
>> +			.size_out = size_out,
>> +			.payload_out = feat_out + data_rcvd_size,
>> +			.min_out = data_to_rd_size,
>> +		};
>> +		rc = cxl_internal_send_cmd(mds, &mbox_cmd);
>> +		if (rc < 0 || mbox_cmd.size_out == 0)
>Is there other case when size_out will be 0 other than the feat_out_size is 0?
I think size_out can be 0 depending on the implementation on the firmware or some
error situation when the feat_out_size is non zero.

>
>If feat_out_size is 0, maybe we return directly, or we use while () {}, instead of
>do {} while.
I had a check for feat_out_size against min feat out size in the previous version. 
Will add return directly if feat_out_size is 0.  
>Anyway, if there is no other case that will return size_out as 0, we can avoid the
>check.
>
>Fan
>> +			return 0;
>> +		data_rcvd_size += mbox_cmd.size_out;
>> +	} while (data_rcvd_size < feat_out_size);
>> +
>> +	return data_rcvd_size;
>> +}
>> +EXPORT_SYMBOL_NS_GPL(cxl_get_feature, CXL);
>> +
>>  int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
>>  		       struct cxl_region *cxlr)
>>  {
>> diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h index
>> b0e1565b9d2e..25698a6fbe66 100644
>> --- a/drivers/cxl/cxlmem.h
>> +++ b/drivers/cxl/cxlmem.h
>> @@ -531,6 +531,7 @@ enum cxl_opcode {
>>  	CXL_MBOX_OP_CLEAR_LOG           = 0x0403,
>>  	CXL_MBOX_OP_GET_SUP_LOG_SUBLIST = 0x0405,
>>  	CXL_MBOX_OP_GET_SUPPORTED_FEATURES	= 0x0500,
>> +	CXL_MBOX_OP_GET_FEATURE		= 0x0501,
>>  	CXL_MBOX_OP_IDENTIFY		= 0x4000,
>>  	CXL_MBOX_OP_GET_PARTITION_INFO	= 0x4100,
>>  	CXL_MBOX_OP_SET_PARTITION_INFO	= 0x4101,
>> @@ -757,6 +758,28 @@ struct cxl_mbox_get_supp_feats_out {
>>  	struct cxl_mbox_supp_feat_entry feat_entries[];  } __packed;
>>
>> +/*
>> + * Get Feature CXL 3.1 Spec 8.2.9.6.2  */
>> +
>> +/*
>> + * Get Feature input payload
>> + * CXL rev 3.1 section 8.2.9.6.2 Table 8-99  */ enum
>> +cxl_get_feat_selection {
>> +	CXL_GET_FEAT_SEL_CURRENT_VALUE,
>> +	CXL_GET_FEAT_SEL_DEFAULT_VALUE,
>> +	CXL_GET_FEAT_SEL_SAVED_VALUE,
>> +	CXL_GET_FEAT_SEL_MAX
>> +};
>> +
>> +struct cxl_mbox_get_feat_in {
>> +	uuid_t uuid;
>> +	__le16 offset;
>> +	__le16 count;
>> +	u8 selection;
>> +}  __packed;
>> +
>>  /* Get Poison List  CXL 3.0 Spec 8.2.9.8.4.1 */  struct
>> cxl_mbox_poison_in {
>>  	__le64 offset;
>> @@ -891,6 +914,10 @@ int cxl_set_timestamp(struct cxl_memdev_state
>> *mds);  int cxl_get_supported_features(struct cxl_memdev_state *mds,
>>  			       u32 count, u16 start_index,
>>  			       struct cxl_mbox_get_supp_feats_out *feats_out);
>> +size_t cxl_get_feature(struct cxl_memdev_state *mds,
>> +		       const uuid_t feat_uuid, void *feat_out,
>> +		       size_t feat_out_size,
>> +		       enum cxl_get_feat_selection selection);
>>  int cxl_poison_state_init(struct cxl_memdev_state *mds);  int
>> cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
>>  		       struct cxl_region *cxlr);
>> --
>> 2.34.1
>>

Thanks,
Shiju
diff mbox series

Patch

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 9b9b1d26454e..b1eeed508459 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -1351,6 +1351,43 @@  int cxl_get_supported_features(struct cxl_memdev_state *mds,
 }
 EXPORT_SYMBOL_NS_GPL(cxl_get_supported_features, CXL);
 
+size_t cxl_get_feature(struct cxl_memdev_state *mds,
+		       const uuid_t feat_uuid, void *feat_out,
+		       size_t feat_out_size,
+		       enum cxl_get_feat_selection selection)
+{
+	size_t data_to_rd_size, size_out;
+	struct cxl_mbox_get_feat_in pi;
+	struct cxl_mbox_cmd mbox_cmd;
+	size_t data_rcvd_size = 0;
+	int rc;
+
+	size_out = min(feat_out_size, mds->payload_size);
+	pi.uuid = feat_uuid;
+	pi.selection = selection;
+	do {
+		data_to_rd_size = min(feat_out_size - data_rcvd_size, mds->payload_size);
+		pi.offset = cpu_to_le16(data_rcvd_size);
+		pi.count = cpu_to_le16(data_to_rd_size);
+
+		mbox_cmd = (struct cxl_mbox_cmd) {
+			.opcode = CXL_MBOX_OP_GET_FEATURE,
+			.size_in = sizeof(pi),
+			.payload_in = &pi,
+			.size_out = size_out,
+			.payload_out = feat_out + data_rcvd_size,
+			.min_out = data_to_rd_size,
+		};
+		rc = cxl_internal_send_cmd(mds, &mbox_cmd);
+		if (rc < 0 || mbox_cmd.size_out == 0)
+			return 0;
+		data_rcvd_size += mbox_cmd.size_out;
+	} while (data_rcvd_size < feat_out_size);
+
+	return data_rcvd_size;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_get_feature, CXL);
+
 int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
 		       struct cxl_region *cxlr)
 {
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index b0e1565b9d2e..25698a6fbe66 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -531,6 +531,7 @@  enum cxl_opcode {
 	CXL_MBOX_OP_CLEAR_LOG           = 0x0403,
 	CXL_MBOX_OP_GET_SUP_LOG_SUBLIST = 0x0405,
 	CXL_MBOX_OP_GET_SUPPORTED_FEATURES	= 0x0500,
+	CXL_MBOX_OP_GET_FEATURE		= 0x0501,
 	CXL_MBOX_OP_IDENTIFY		= 0x4000,
 	CXL_MBOX_OP_GET_PARTITION_INFO	= 0x4100,
 	CXL_MBOX_OP_SET_PARTITION_INFO	= 0x4101,
@@ -757,6 +758,28 @@  struct cxl_mbox_get_supp_feats_out {
 	struct cxl_mbox_supp_feat_entry feat_entries[];
 } __packed;
 
+/*
+ * Get Feature CXL 3.1 Spec 8.2.9.6.2
+ */
+
+/*
+ * Get Feature input payload
+ * CXL rev 3.1 section 8.2.9.6.2 Table 8-99
+ */
+enum cxl_get_feat_selection {
+	CXL_GET_FEAT_SEL_CURRENT_VALUE,
+	CXL_GET_FEAT_SEL_DEFAULT_VALUE,
+	CXL_GET_FEAT_SEL_SAVED_VALUE,
+	CXL_GET_FEAT_SEL_MAX
+};
+
+struct cxl_mbox_get_feat_in {
+	uuid_t uuid;
+	__le16 offset;
+	__le16 count;
+	u8 selection;
+}  __packed;
+
 /* Get Poison List  CXL 3.0 Spec 8.2.9.8.4.1 */
 struct cxl_mbox_poison_in {
 	__le64 offset;
@@ -891,6 +914,10 @@  int cxl_set_timestamp(struct cxl_memdev_state *mds);
 int cxl_get_supported_features(struct cxl_memdev_state *mds,
 			       u32 count, u16 start_index,
 			       struct cxl_mbox_get_supp_feats_out *feats_out);
+size_t cxl_get_feature(struct cxl_memdev_state *mds,
+		       const uuid_t feat_uuid, void *feat_out,
+		       size_t feat_out_size,
+		       enum cxl_get_feat_selection selection);
 int cxl_poison_state_init(struct cxl_memdev_state *mds);
 int cxl_mem_get_poison(struct cxl_memdev *cxlmd, u64 offset, u64 len,
 		       struct cxl_region *cxlr);