[PATCH v3 15/27] powerpc/powernv/pmem: 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>
---
 arch/powerpc/platforms/powernv/pmem/ocxl.c    |  6 +++
 .../platforms/powernv/pmem/ocxl_internal.c    | 41 +++++++++++++++++++
 .../platforms/powernv/pmem/ocxl_internal.h    | 37 +++++++++++++++++
 3 files changed, 84 insertions(+)

diff --git a/arch/powerpc/platforms/powernv/pmem/ocxl.c b/arch/powerpc/platforms/powernv/pmem/ocxl.c
index 4e782d22605b..b8bd7e703b19 100644
--- a/arch/powerpc/platforms/powernv/pmem/ocxl.c
+++ b/arch/powerpc/platforms/powernv/pmem/ocxl.c
@@ -259,12 +259,18 @@ static int setup_command_metadata(struct ocxlpmem *ocxlpmem)
 	int rc;
 
 	mutex_init(&ocxlpmem->admin_command.lock);
+	mutex_init(&ocxlpmem->ns_command.lock);
 
 	rc = extract_command_metadata(ocxlpmem, GLOBAL_MMIO_ACMA_CREQO,
 				      &ocxlpmem->admin_command);
 	if (rc)
 		return rc;
 
+	rc = extract_command_metadata(ocxlpmem, GLOBAL_MMIO_NSCMA_CREQO,
+					  &ocxlpmem->ns_command);
+	if (rc)
+		return rc;
+
 	return 0;
 }
 
diff --git a/arch/powerpc/platforms/powernv/pmem/ocxl_internal.c b/arch/powerpc/platforms/powernv/pmem/ocxl_internal.c
index 583f48023025..3e0b133feddf 100644
--- a/arch/powerpc/platforms/powernv/pmem/ocxl_internal.c
+++ b/arch/powerpc/platforms/powernv/pmem/ocxl_internal.c
@@ -133,6 +133,47 @@ int admin_response_handled(const struct ocxlpmem *ocxlpmem)
 				      OCXL_LITTLE_ENDIAN, GLOBAL_MMIO_CHI_ACRA);
 }
 
+int ns_command_request(struct ocxlpmem *ocxlpmem, u8 op_code)
+{
+	u64 val;
+	int rc = ocxl_global_mmio_read64(ocxlpmem->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(ocxlpmem, &ocxlpmem->ns_command, op_code);
+}
+
+int ns_response(const struct ocxlpmem *ocxlpmem)
+{
+	return command_response(ocxlpmem, &ocxlpmem->ns_command);
+}
+
+int ns_command_execute(const struct ocxlpmem *ocxlpmem)
+{
+	return ocxl_global_mmio_set64(ocxlpmem->ocxl_afu, GLOBAL_MMIO_HCI,
+				      OCXL_LITTLE_ENDIAN, GLOBAL_MMIO_HCI_NSCRW);
+}
+
+bool ns_command_complete(const struct ocxlpmem *ocxlpmem)
+{
+	u64 val = 0;
+	int rc = ocxlpmem_chi(ocxlpmem, &val);
+
+	WARN_ON(rc);
+
+	return (val & GLOBAL_MMIO_CHI_NSCRA) != 0;
+}
+
+int ns_response_handled(const struct ocxlpmem *ocxlpmem)
+{
+	return ocxl_global_mmio_set64(ocxlpmem->ocxl_afu, GLOBAL_MMIO_CHIC,
+				      OCXL_LITTLE_ENDIAN, GLOBAL_MMIO_CHI_NSCRA);
+}
+
 void warn_status(const struct ocxlpmem *ocxlpmem, const char *message,
 		     u8 status)
 {
diff --git a/arch/powerpc/platforms/powernv/pmem/ocxl_internal.h b/arch/powerpc/platforms/powernv/pmem/ocxl_internal.h
index 2fef68c71271..28e2020f6355 100644
--- a/arch/powerpc/platforms/powernv/pmem/ocxl_internal.h
+++ b/arch/powerpc/platforms/powernv/pmem/ocxl_internal.h
@@ -107,6 +107,7 @@ struct ocxlpmem {
 	struct ocxl_context *ocxl_context;
 	void *metadata_addr;
 	struct command_metadata admin_command;
+	struct command_metadata ns_command;
 	struct resource pmem_res;
 	struct nd_region *nd_region;
 	char fw_version[8+1];
@@ -175,6 +176,42 @@ int admin_command_complete_timeout(const struct ocxlpmem *ocxlpmem,
  */
 int admin_response_handled(const struct ocxlpmem *ocxlpmem);
 
+/**
+ * ns_command_request() - Issue a near storage command request
+ * @ocxlpmem: the device metadata
+ * @op_code: The op-code for the command
+ * Returns an identifier for the command, or negative on error
+ */
+int ns_command_request(struct ocxlpmem *ocxlpmem, u8 op_code);
+
+/**
+ * ns_response() - Validate a near storage response
+ * @ocxlpmem: the device metadata
+ * Returns the status code of the command, or negative on error
+ */
+int ns_response(const struct ocxlpmem *ocxlpmem);
+
+/**
+ * ns_command_execute() - Notify the controller to start processing a pending near storage command
+ * @ocxlpmem: the device metadata
+ * Returns 0 on success, negative on error
+ */
+int ns_command_execute(const struct ocxlpmem *ocxlpmem);
+
+/**
+ * ns_command_complete() - Is a near storage command executing
+ * @ocxlpmem: the device metadata
+ * Returns true if the previous admin command has completed
+ */
+bool ns_command_complete(const struct ocxlpmem *ocxlpmem);
+
+/**
+ * ns_response_handled() - Notify the controller that the near storage response has been handled
+ * @ocxlpmem: the device metadata
+ * Returns 0 on success, negative on failure
+ */
+int ns_response_handled(const struct ocxlpmem *ocxlpmem);
+
 /**
  * warn_status() - Emit a kernel warning showing a command status.
  * @ocxlpmem: the device metadata
-- 
2.24.1