[RFC PATCH v6 03/12] cxl/mbox: Add SET_FEATURE mailbox command

[shiju.jose]

From: Shiju Jose <shiju.jose@xxxxxxxxxx>

Add support for SET_FEATURE mailbox command.

CXL spec 3.1 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.

Signed-off-by: Shiju Jose <shiju.jose@xxxxxxxxxx>
---
 drivers/cxl/core/mbox.c | 14 ++++++++++++++
 drivers/cxl/cxlmem.h    | 27 +++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index f43189b6859a..056576862b8a 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -1335,6 +1335,20 @@ int cxl_get_feature(struct cxl_memdev_state *mds,
 }
 EXPORT_SYMBOL_NS_GPL(cxl_get_feature, CXL);
 
+int cxl_set_feature(struct cxl_memdev_state *mds, void *feat_in, size_t size)
+{
+	struct cxl_mbox_cmd mbox_cmd;
+
+	mbox_cmd = (struct cxl_mbox_cmd) {
+		.opcode = CXL_MBOX_OP_SET_FEATURE,
+		.size_in = size,
+		.payload_in = feat_in,
+	};
+
+	return cxl_internal_send_cmd(mds, &mbox_cmd);
+}
+EXPORT_SYMBOL_NS_GPL(cxl_set_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 eaecc3234cfd..2223ef3d3140 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -531,6 +531,7 @@ enum cxl_opcode {
 	CXL_MBOX_OP_GET_LOG		= 0x0401,
 	CXL_MBOX_OP_GET_SUPPORTED_FEATURES	= 0x0500,
 	CXL_MBOX_OP_GET_FEATURE		= 0x0501,
+	CXL_MBOX_OP_SET_FEATURE		= 0x0502,
 	CXL_MBOX_OP_IDENTIFY		= 0x4000,
 	CXL_MBOX_OP_GET_PARTITION_INFO	= 0x4100,
 	CXL_MBOX_OP_SET_PARTITION_INFO	= 0x4101,
@@ -778,6 +779,31 @@ struct cxl_mbox_get_feat_in {
 	u8 selection;
 }  __packed;
 
+/* Set Feature CXL 3.1 Spec 8.2.9.6.3 */
+/*
+ * Set Feature input payload
+ * CXL rev 3.1 section 8.2.9.6.3 Table 8-101
+ */
+/* Set Feature : Payload in flags */
+#define CXL_SET_FEAT_FLAG_DATA_TRANSFER_MASK	GENMASK(2, 0)
+enum cxl_set_feat_flag_data_transfer {
+	CXL_SET_FEAT_FLAG_FULL_DATA_TRANSFER,
+	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_MOD_VALUE_SAVED_ACROSS_RESET	BIT(3)
+
+struct cxl_mbox_set_feat_in {
+	uuid_t uuid;
+	__le32 flags;
+	__le16 offset;
+	u8 version;
+	u8 rsvd[9];
+}  __packed;
+
 /* Get Poison List  CXL 3.0 Spec 8.2.9.8.4.1 */
 struct cxl_mbox_poison_in {
 	__le64 offset;
@@ -914,6 +940,7 @@ int cxl_get_supported_features(struct cxl_memdev_state *mds,
 			       void *feats_out);
 int cxl_get_feature(struct cxl_memdev_state *mds,
 		    struct cxl_mbox_get_feat_in *pi, void *feat_out);
+int cxl_set_feature(struct cxl_memdev_state *mds, void *feat_in, size_t size);
 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