[PATCH v13 16/18] cxl/mbox: Add support for PERFORM_MAINTENANCE mailbox command

[shiju.jose]

From: Shiju Jose <shiju.jose@xxxxxxxxxx>

Add support for PERFORM_MAINTENANCE mailbox command.

CXL spec 3.1 section 8.2.9.7.1 describes the Perform Maintenance command.
This command requests the device to execute the maintenance operation
specified by the maintenance operation class and the maintenance operation
subclass.

Signed-off-by: Shiju Jose <shiju.jose@xxxxxxxxxx>
---
 drivers/cxl/core/mbox.c | 40 ++++++++++++++++++++++++++++++++++++++++
 drivers/cxl/cxlmem.h    | 17 +++++++++++++++++
 2 files changed, 57 insertions(+)

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index 30c44ab11347..a6f69864c504 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -1084,6 +1084,46 @@ int cxl_set_feature(struct cxl_memdev_state *mds,
 }
 EXPORT_SYMBOL_NS_GPL(cxl_set_feature, CXL);
 
+int cxl_do_maintenance(struct cxl_memdev_state *mds,
+		       u8 class, u8 subclass,
+		       void *data_in, size_t data_in_size)
+{
+	struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
+	struct cxl_memdev_maintenance_pi {
+		struct cxl_mbox_do_maintenance_hdr hdr;
+		u8 data[];
+	}  __packed;
+	struct cxl_mbox_cmd mbox_cmd;
+	size_t hdr_size;
+	int rc = 0;
+
+	struct cxl_memdev_maintenance_pi *pi __free(kfree) =
+					kmalloc(cxl_mbox->payload_size, GFP_KERNEL);
+	pi->hdr.op_class = class;
+	pi->hdr.op_subclass = subclass;
+	hdr_size = sizeof(pi->hdr);
+	/*
+	 * Check minimum mbox payload size is available for
+	 * the maintenance data transfer.
+	 */
+	if (hdr_size + data_in_size > cxl_mbox->payload_size)
+		return -ENOMEM;
+
+	memcpy(pi->data, data_in, data_in_size);
+	mbox_cmd = (struct cxl_mbox_cmd) {
+		.opcode = CXL_MBOX_OP_DO_MAINTENANCE,
+		.size_in = hdr_size + data_in_size,
+		.payload_in = pi,
+	};
+
+	rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
+	if (rc < 0)
+		return rc;
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_do_maintenance, 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 e1156ea93fe7..1cd50ada551b 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -531,6 +531,7 @@ enum cxl_opcode {
 	CXL_MBOX_OP_GET_SUPPORTED_FEATURES	= 0x0500,
 	CXL_MBOX_OP_GET_FEATURE		= 0x0501,
 	CXL_MBOX_OP_SET_FEATURE		= 0x0502,
+	CXL_MBOX_OP_DO_MAINTENANCE	= 0x0600,
 	CXL_MBOX_OP_IDENTIFY		= 0x4000,
 	CXL_MBOX_OP_GET_PARTITION_INFO	= 0x4100,
 	CXL_MBOX_OP_SET_PARTITION_INFO	= 0x4101,
@@ -907,6 +908,19 @@ struct cxl_mbox_set_feat_hdr {
 	u8 rsvd[9];
 }  __packed;
 
+/*
+ * Perform Maintenance CXL 3.1 Spec 8.2.9.7.1
+ */
+
+/*
+ * Perform Maintenance input payload
+ * CXL rev 3.1 section 8.2.9.7.1 Table 8-102
+ */
+struct cxl_mbox_do_maintenance_hdr {
+	u8 op_class;
+	u8 op_subclass;
+}  __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);
@@ -984,4 +998,7 @@ int cxl_set_feature(struct cxl_memdev_state *mds,
 		    const uuid_t feat_uuid, u8 feat_version,
 		    void *feat_data, size_t feat_data_size,
 		    u8 feat_flag);
+int cxl_do_maintenance(struct cxl_memdev_state *mds,
+		       u8 class, u8 subclass,
+		       void *data_in, size_t data_in_size);
 #endif /* __CXL_MEM_H__ */
-- 
2.34.1