Commit 5e5ac21f authored by Shiju Jose's avatar Shiju Jose Committed by Dave Jiang
Browse files

cxl/mbox: Add GET_FEATURE mailbox command 



Add support for GET_FEATURE mailbox command.

CXL spec r3.2 section 8.2.9.6 describes optional device specific features.
The settings of a feature can be retrieved using Get Feature command.
CXL spec r3.2 section 8.2.9.6.2 describes Get Feature command.

Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: default avatarLi Ming <ming.li@zohomail.com>
Reviewed-by: default avatarDan Williams <dan.j.williams@intel.com>
Signed-off-by: default avatarShiju Jose <shiju.jose@huawei.com>
Link: https://patch.msgid.link/20250220194438.2281088-5-dave.jiang@intel.com


Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
parent 44818d38

drivers/cxl/core/core.h

+7 −0
Original line number Diff line number Diff line
@@ -117,4 +117,11 @@ bool cxl_need_node_perf_attrs_update(int nid); 
int cxl_port_get_switch_dport_bandwidth(struct cxl_port *port,

					struct access_coordinate *c);



#ifdef CONFIG_CXL_FEATURES

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);

#endif



#endif /* __CXL_CORE_H__ */

drivers/cxl/core/features.c

+50 −0
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
#include <cxl/mailbox.h>

#include <cxl/features.h>

#include "cxl.h"

#include "core.h"

#include "cxlmem.h"



inline struct cxl_features_state *to_cxlfs(struct cxl_dev_state *cxlds)
@@ -173,3 +174,52 @@ int devm_cxl_setup_features(struct cxl_dev_state *cxlds) 
	return devm_add_action_or_reset(cxlds->dev, free_cxlfs, no_free_ptr(cxlfs));

}

EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_features, "CXL");



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)

{

	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;



	if (return_code)

		*return_code = CXL_MBOX_CMD_RC_INPUT;



	if (!feat_out || !feat_out_size)

		return 0;



	size_out = min(feat_out_size, cxl_mbox->payload_size);

	uuid_copy(&pi.uuid, feat_uuid);

	pi.selection = selection;

	do {

		data_to_rd_size = min(feat_out_size - data_rcvd_size,

				      cxl_mbox->payload_size);

		pi.offset = cpu_to_le16(offset + 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(cxl_mbox, &mbox_cmd);

		if (rc < 0 || !mbox_cmd.size_out) {

			if (return_code)

				*return_code = mbox_cmd.return_code;

			return 0;

		}

		data_rcvd_size += mbox_cmd.size_out;

	} while (data_rcvd_size < feat_out_size);



	if (return_code)

		*return_code = CXL_MBOX_CMD_RC_SUCCESS;



	return data_rcvd_size;

}

include/cxl/features.h

+24 −0
Original line number Diff line number Diff line
@@ -67,6 +67,29 @@ struct cxl_mbox_get_sup_feats_out { 
	struct cxl_feat_entry ents[] __counted_by_le(num_entries);

} __packed;



/*

 * Get Feature CXL spec r3.2 Spec 8.2.9.6.2

 */



/*

 * Get Feature input payload

 * CXL spec r3.2 section 8.2.9.6.2 Table 8-99

 */

struct cxl_mbox_get_feat_in {

	uuid_t uuid;

	__le16 offset;

	__le16 count;

	u8 selection;

}  __packed;



/* Selection field for 'struct cxl_mbox_get_feat_in' */

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_features_state - The Features state for the device

 * @cxlds: Pointer to CXL device state
@@ -82,6 +105,7 @@ struct cxl_features_state { 
	} *entries;

};



struct cxl_mailbox;

#ifdef CONFIG_CXL_FEATURES

inline struct cxl_features_state *to_cxlfs(struct cxl_dev_state *cxlds);

int devm_cxl_setup_features(struct cxl_dev_state *cxlds);