[PATCH v2 14/27] nvdimm/ocxl: Add support for near storage commands

[Alastair D'Silva]

From: Alastair D'Silva <alastair at d-silva.org>

Similar to the previous patch, this adds support for near storage commands.

Signed-off-by: Alastair D'Silva <alastair at d-silva.org>
---
 drivers/nvdimm/ocxl/scm.c          |  6 +++++
 drivers/nvdimm/ocxl/scm_internal.c | 41 ++++++++++++++++++++++++++++++
 drivers/nvdimm/ocxl/scm_internal.h | 38 +++++++++++++++++++++++++++
 3 files changed, 85 insertions(+)

diff --git a/drivers/nvdimm/ocxl/scm.c b/drivers/nvdimm/ocxl/scm.c
index 1e175f3c3cf2..6c16ca7fabfa 100644
--- a/drivers/nvdimm/ocxl/scm.c
+++ b/drivers/nvdimm/ocxl/scm.c
@@ -310,12 +310,18 @@ static int scm_setup_command_metadata(struct scm_data *scm_data)
 	int rc;
 
 	mutex_init(&scm_data->admin_command.lock);
+	mutex_init(&scm_data->ns_command.lock);
 
 	rc = scm_extract_command_metadata(scm_data, GLOBAL_MMIO_ACMA_CREQO,
 					  &scm_data->admin_command);
 	if (rc)
 		return rc;
 
+	rc = scm_extract_command_metadata(scm_data, GLOBAL_MMIO_NSCMA_CREQO,
+					  &scm_data->ns_command);
+	if (rc)
+		return rc;
+
 	return 0;
 }
 
diff --git a/drivers/nvdimm/ocxl/scm_internal.c b/drivers/nvdimm/ocxl/scm_internal.c
index 7b11b56863fb..c405f1d8afb8 100644
--- a/drivers/nvdimm/ocxl/scm_internal.c
+++ b/drivers/nvdimm/ocxl/scm_internal.c
@@ -132,6 +132,47 @@ int scm_admin_response_handled(const struct scm_data *scm_data)
 				      OCXL_LITTLE_ENDIAN, GLOBAL_MMIO_CHI_ACRA);
 }
 
+int scm_ns_command_request(struct scm_data *scm_data, u8 op_code)
+{
+	u64 val;
+	int rc = ocxl_global_mmio_read64(scm_data->ocxl_afu, GLOBAL_MMIO_CHI,
+					 OCXL_LITTLE_ENDIAN, &val);
+	if (rc)
+		return rc;
+
+	if (!(val & GLOBAL_MMIO_CHI_NSCRA))
+		return -EBUSY;
+
+	return scm_command_request(scm_data, &scm_data->ns_command, op_code);
+}
+
+int scm_ns_response(const struct scm_data *scm_data)
+{
+	return scm_command_response(scm_data, &scm_data->ns_command);
+}
+
+int scm_ns_command_execute(const struct scm_data *scm_data)
+{
+	return ocxl_global_mmio_set64(scm_data->ocxl_afu, GLOBAL_MMIO_HCI,
+				      OCXL_LITTLE_ENDIAN, GLOBAL_MMIO_HCI_NSCRW);
+}
+
+bool scm_ns_command_complete(const struct scm_data *scm_data)
+{
+	u64 val = 0;
+	int rc = scm_chi(scm_data, &val);
+
+	WARN_ON(rc);
+
+	return (val & GLOBAL_MMIO_CHI_NSCRA) != 0;
+}
+
+int scm_ns_response_handled(const struct scm_data *scm_data)
+{
+	return ocxl_global_mmio_set64(scm_data->ocxl_afu, GLOBAL_MMIO_CHIC,
+				      OCXL_LITTLE_ENDIAN, GLOBAL_MMIO_CHI_NSCRA);
+}
+
 void scm_warn_status(const struct scm_data *scm_data, const char *message,
 		     u8 status)
 {
diff --git a/drivers/nvdimm/ocxl/scm_internal.h b/drivers/nvdimm/ocxl/scm_internal.h
index 9bff684cd069..9575996a89e7 100644
--- a/drivers/nvdimm/ocxl/scm_internal.h
+++ b/drivers/nvdimm/ocxl/scm_internal.h
@@ -108,6 +108,7 @@ struct scm_data {
 	struct ocxl_context *ocxl_context;
 	void *metadata_addr;
 	struct command_metadata admin_command;
+	struct command_metadata ns_command;
 	struct resource scm_res;
 	struct nd_region *nd_region;
 	char fw_version[8+1];
@@ -176,6 +177,42 @@ int scm_admin_command_complete_timeout(const struct scm_data *scm_data,
  */
 int scm_admin_response_handled(const struct scm_data *scm_data);
 
+/**
+ * scm_ns_command_request() - Issue a near storage command request
+ * @scm_data: a pointer to the SCM device data
+ * @op_code: The op-code for the command
+ * Returns an identifier for the command, or negative on error
+ */
+int scm_ns_command_request(struct scm_data *scm_data, u8 op_code);
+
+/**
+ * scm_ns_response() - Validate a near storage response
+ * @scm_data: a pointer to the SCM device data
+ * Returns the status code of the command, or negative on error
+ */
+int scm_ns_response(const struct scm_data *scm_data);
+
+/**
+ * scm_ns_command_execute() - Notify the controller to start processing a pending near storage command
+ * @scm_data: a pointer to the SCM device data
+ * Returns 0 on success, negative on error
+ */
+int scm_ns_command_execute(const struct scm_data *scm_data);
+
+/**
+ * scm_ns_command_complete() - Is a near storage command executing
+ * scm_data: a pointer to the SCM device data
+ * Returns true if the previous admin command has completed
+ */
+bool scm_ns_command_complete(const struct scm_data *scm_data);
+
+/**
+ * scm_ns_response_handled() - Notify the controller that the near storage response has been handled
+ * scm_data: a pointer to the SCM device data
+ * Returns 0 on success, negative on failure
+ */
+int scm_ns_response_handled(const struct scm_data *scm_data);
+
 /**
  * scm_warn_status() - Emit a kernel warning showing a command status.
  * @scm_data: a pointer to the SCM device data
@@ -184,3 +221,4 @@ int scm_admin_response_handled(const struct scm_data *scm_data);
  */
 void scm_warn_status(const struct scm_data *scm_data, const char *message,
 		     u8 status);
+
-- 
2.23.0