[PATCH v13 08/18] cxl/mbox: Add GET_FEATURE mailbox command

shiju.jose
2024-10-09T12:43:24Z

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.
CXL spec 3.1 section 8.2.9.6.2 describes Get Feature command.

Reviewed-by: Fan Ni <fan.ni@samsung.com>
Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
---
drivers/cxl/core/mbox.c | 41 +++++++++++++++++++++++++++++++++++++++++
drivers/cxl/cxlmem.h | 26 ++++++++++++++++++++++++++
2 files changed, 67 insertions(+)

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 6493cad8c325..eae374a90a9f 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -970,6 +970,47 @@ int cxl_get_supported_feature_entry(struct cxl_memdev_state *mds, const uuid_t *
}
EXPORT_SYMBOL_NS_GPL(cxl_get_supported_feature_entry, CXL);

+size_t cxl_get_feature(struct cxl_memdev_state *mds, const uuid_t feat_uuid,
+ enum cxl_get_feat_selection selection,
+ void *feat_out, size_t feat_out_size)
+{
+ struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
+ 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 (!feat_out || !feat_out_size)
+ return 0;
+
+ size_out = min(feat_out_size, cxl_mbox->payload_size);
+ 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(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)
+ 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);
+
/**
* cxl_enumerate_cmds() - Enumerate commands for a device.
* @mds: The driver data for the operation
diff --git a/drivers/cxl/cxlmem.h b/drivers/cxl/cxlmem.h
index 94ce4645e605..c7ad63597709 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -529,6 +529,7 @@ 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,
@@ -854,6 +855,28 @@ struct cxl_mbox_get_sup_feats_out {
struct cxl_feat_entry ents[] __counted_by_le(supported_feats);
} __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;
+
int cxl_internal_send_cmd(struct cxl_mailbox *cxl_mbox,
struct cxl_mbox_cmd *cmd);
int cxl_dev_state_identify(struct cxl_memdev_state *mds);
@@ -917,4 +940,7 @@ void cxl_dpa_debug(struct seq_file *file, struct cxl_dev_state *cxlds);
int cxl_get_supported_features(struct cxl_memdev_state *mds);
int cxl_get_supported_feature_entry(struct cxl_memdev_state *mds, const uuid_t *feat_uuid,
struct cxl_feat_entry *feat_entry_out);
+size_t cxl_get_feature(struct cxl_memdev_state *mds, const uuid_t feat_uuid,
+ enum cxl_get_feat_selection selection,
+ void *feat_out, size_t feat_out_size);
#endif /* __CXL_MEM_H__ */
--
2.34.1