From: Shiju Jose Date: Thu, 20 Feb 2025 19:42:42 +0000 (-0700) Subject: cxl/mbox: Add GET_FEATURE mailbox command X-Git-Tag: v6.15-rc1~45^2~1^2~2 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5e5ac21f629de796ab5d598b59c5e468c6fe4f95;p=thirdparty%2Fkernel%2Flinux.git 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: Jonathan Cameron Reviewed-by: Li Ming Reviewed-by: Dan Williams Signed-off-by: Shiju Jose Link: https://patch.msgid.link/20250220194438.2281088-5-dave.jiang@intel.com Signed-off-by: Dave Jiang --- diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h index f77fcf71ade51..7cd3b98150e61 100644 --- a/drivers/cxl/core/core.h +++ b/drivers/cxl/core/core.h @@ -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__ */ diff --git a/drivers/cxl/core/features.c b/drivers/cxl/core/features.c index f2898a56bd634..3fc6f8415f191 100644 --- a/drivers/cxl/core/features.c +++ b/drivers/cxl/core/features.c @@ -4,6 +4,7 @@ #include #include #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; +} diff --git a/include/cxl/features.h b/include/cxl/features.h index 5b3485eb0f774..766c09978e5e1 100644 --- a/include/cxl/features.h +++ b/include/cxl/features.h @@ -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);