Commit 14d502cc authored by Shiju Jose's avatar Shiju Jose Committed by Dave Jiang
Browse files

cxl/mbox: Add SET_FEATURE mailbox command 



Add support for SET_FEATURE mailbox command.

CXL spec r3.2 section 8.2.9.6 describes optional device specific features.
CXL devices supports features with changeable attributes.
The settings of a feature can be optionally modified using Set Feature
command.
CXL spec r3.2 section 8.2.9.6.3 describes Set Feature command.

Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Reviewed-by: default avatarLi Ming <ming.li@zohomail.com>
Signed-off-by: default avatarShiju Jose <shiju.jose@huawei.com>
Link: https://patch.msgid.link/20250220194438.2281088-6-dave.jiang@intel.com


Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
parent 5e5ac21f

drivers/cxl/core/core.h

+4 −0
Original line number Diff line number Diff line
@@ -122,6 +122,10 @@ size_t cxl_get_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid, 
		       enum cxl_get_feat_selection selection,

		       void *feat_out, size_t feat_out_size, u16 offset,

		       u16 *return_code);

int cxl_set_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid,

		    u8 feat_version, const void *feat_data,

		    size_t feat_data_size, u32 feat_flag, u16 offset,

		    u16 *return_code);

#endif



#endif /* __CXL_CORE_H__ */

drivers/cxl/core/features.c

+80 −0
Original line number Diff line number Diff line
@@ -223,3 +223,83 @@ size_t cxl_get_feature(struct cxl_mailbox *cxl_mbox, const uuid_t *feat_uuid, 


	return data_rcvd_size;

}



/*

 * FEAT_DATA_MIN_PAYLOAD_SIZE - min extra number of bytes should be

 * available in the mailbox for storing the actual feature data so that

 * the feature data transfer would work as expected.

 */

#define FEAT_DATA_MIN_PAYLOAD_SIZE 10

int cxl_set_feature(struct cxl_mailbox *cxl_mbox,

		    const uuid_t *feat_uuid, u8 feat_version,

		    const void *feat_data, size_t feat_data_size,

		    u32 feat_flag, u16 offset, u16 *return_code)

{

	size_t data_in_size, data_sent_size = 0;

	struct cxl_mbox_cmd mbox_cmd;

	size_t hdr_size;



	if (return_code)

		*return_code = CXL_MBOX_CMD_RC_INPUT;



	struct cxl_mbox_set_feat_in *pi __free(kfree) =

			kzalloc(cxl_mbox->payload_size, GFP_KERNEL);

	if (!pi)

		return -ENOMEM;



	uuid_copy(&pi->uuid, feat_uuid);

	pi->version = feat_version;

	feat_flag &= ~CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK;

	feat_flag |= CXL_SET_FEAT_FLAG_DATA_SAVED_ACROSS_RESET;

	hdr_size = sizeof(pi->hdr);

	/*

	 * Check minimum mbox payload size is available for

	 * the feature data transfer.

	 */

	if (hdr_size + FEAT_DATA_MIN_PAYLOAD_SIZE > cxl_mbox->payload_size)

		return -ENOMEM;



	if (hdr_size + feat_data_size <= cxl_mbox->payload_size) {

		pi->flags = cpu_to_le32(feat_flag |

					CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER);

		data_in_size = feat_data_size;

	} else {

		pi->flags = cpu_to_le32(feat_flag |

					CXL_SET_FEAT_FLAG_INITIATE_DATA_TRANSFER);

		data_in_size = cxl_mbox->payload_size - hdr_size;

	}



	do {

		int rc;



		pi->offset = cpu_to_le16(offset + data_sent_size);

		memcpy(pi->feat_data, feat_data + data_sent_size, data_in_size);

		mbox_cmd = (struct cxl_mbox_cmd) {

			.opcode = CXL_MBOX_OP_SET_FEATURE,

			.size_in = hdr_size + data_in_size,

			.payload_in = pi,

		};

		rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);

		if (rc < 0) {

			if (return_code)

				*return_code = mbox_cmd.return_code;

			return rc;

		}



		data_sent_size += data_in_size;

		if (data_sent_size >= feat_data_size) {

			if (return_code)

				*return_code = CXL_MBOX_CMD_RC_SUCCESS;

			return 0;

		}



		if ((feat_data_size - data_sent_size) <= (cxl_mbox->payload_size - hdr_size)) {

			data_in_size = feat_data_size - data_sent_size;

			pi->flags = cpu_to_le32(feat_flag |

						CXL_SET_FEAT_FLAG_FINISH_DATA_TRANSFER);

		} else {

			pi->flags = cpu_to_le32(feat_flag |

						CXL_SET_FEAT_FLAG_CONTINUE_DATA_TRANSFER);

		}

	} while (true);

}

include/cxl/features.h

+33 −0
Original line number Diff line number Diff line
@@ -90,6 +90,39 @@ enum cxl_get_feat_selection { 
	CXL_GET_FEAT_SEL_MAX

};



/*

 * Set Feature CXL spec r3.2  8.2.9.6.3

 */



/*

 * Set Feature input payload

 * CXL spec r3.2 section 8.2.9.6.3 Table 8-101

 */

struct cxl_mbox_set_feat_in {

	__struct_group(cxl_mbox_set_feat_hdr, hdr, /* no attrs */,

		uuid_t uuid;

		__le32 flags;

		__le16 offset;

		u8 version;

		u8 rsvd[9];

	);

	__u8 feat_data[];

}  __packed;



/* Set Feature flags field */

enum cxl_set_feat_flag_data_transfer {

	CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER = 0,

	CXL_SET_FEAT_FLAG_INITIATE_DATA_TRANSFER,

	CXL_SET_FEAT_FLAG_CONTINUE_DATA_TRANSFER,

	CXL_SET_FEAT_FLAG_FINISH_DATA_TRANSFER,

	CXL_SET_FEAT_FLAG_ABORT_DATA_TRANSFER,

	CXL_SET_FEAT_FLAG_DATA_TRANSFER_MAX

};



#define CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK	GENMASK(2, 0)



#define CXL_SET_FEAT_FLAG_DATA_SAVED_ACROSS_RESET	BIT(3)



/**

 * struct cxl_features_state - The Features state for the device

 * @cxlds: Pointer to CXL device state