[PATCH v11 13/14] cxl/mbox: Add support for PERFORM_MAINTENANCE mailbox command

[<shiju.jose@huawei.com>]

From: Shiju Jose <shiju.jose@huawei.com>

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@huawei.com>
---
 drivers/cxl/core/mbox.c | 39 +++++++++++++++++++++++++++++++++++++++
 drivers/cxl/cxlmem.h    | 17 +++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/drivers/cxl/core/mbox.c b/drivers/cxl/core/mbox.c
index f79269add159..1665365a1e26 100644
--- a/drivers/cxl/core/mbox.c
+++ b/drivers/cxl/core/mbox.c
@@ -1504,6 +1504,45 @@ 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_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(mds->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 > mds->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(mds, &mbox_cmd);
+	if (rc < 0)
+		return rc;
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_do_maintenance, 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 c6f6e38bdbcb..f525eb330dea 100644
--- a/drivers/cxl/cxlmem.h
+++ b/drivers/cxl/cxlmem.h
@@ -534,6 +534,7 @@ 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,
@@ -811,6 +812,19 @@ 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;
+
 /* Get Poison List  CXL 3.0 Spec 8.2.9.8.4.1 */
 struct cxl_mbox_poison_in {
 	__le64 offset;
@@ -955,6 +969,9 @@ 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);
 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