1 files changed, 57 insertions, 0 deletions
diff --git a/drivers/ras/amd/atl/prm.c b/drivers/ras/amd/atl/prm.c
new file mode 100644
index 000000000000..0931a20d213b
--- /dev/null
+++ b/drivers/ras/amd/atl/prm.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AMD Address Translation Library
+ *
+ * prm.c : Plumbing code for ACPI Platform Runtime Mechanism (PRM)
+ *
+ * Information on AMD PRM modules and handlers including the GUIDs and buffer
+ * structures used here are defined in the AMD ACPI Porting Guide in the
+ * chapter "Platform Runtime Mechanism Table (PRMT)"
+ *
+ * Copyright (c) 2024, Advanced Micro Devices, Inc.
+ * All Rights Reserved.
+ *
+ * Author: John Allen <john.allen@amd.com>
+ */
+
+#include "internal.h"
+
+#include <linux/prmt.h>
+
+/*
+ * PRM parameter buffer - normalized to system physical address, as described
+ * in the "PRM Parameter Buffer" section of the AMD ACPI Porting Guide.
+ */
+struct norm_to_sys_param_buf {
+	u64 norm_addr;
+	u8 socket;
+	u64 bank_id;
+	void *out_buf;
+} __packed;
+
+static const guid_t norm_to_sys_guid = GUID_INIT(0xE7180659, 0xA65D, 0x451D,
+						 0x92, 0xCD, 0x2B, 0x56, 0xF1,
+						 0x2B, 0xEB, 0xA6);
+
+unsigned long prm_umc_norm_to_sys_addr(u8 socket_id, u64 bank_id, unsigned long addr)
+{
+	struct norm_to_sys_param_buf p_buf;
+	unsigned long ret_addr;
+	int ret;
+
+	p_buf.norm_addr = addr;
+	p_buf.socket    = socket_id;
+	p_buf.bank_id   = bank_id;
+	p_buf.out_buf   = &ret_addr;
+
+	ret = acpi_call_prm_handler(norm_to_sys_guid, &p_buf);
+	if (!ret)
+		return ret_addr;
+
+	if (ret == -ENODEV)
+		pr_debug("PRM module/handler not available\n");
+	else
+		pr_notice_once("PRM address translation failed\n");
+
+	return ret;
+}