[PATCH v9 2/7] RAS/AMD/ATL: Refactor PRM address translation into a common helper

[Yazen Ghannam <yazen.ghannam@amd.com>]

Every PRM address translation follows the same pattern. Each fills a
parameter buffer, invokes the handler, and checks the result. Only the
handler GUID and the output buffer differ.

Factor the common sequence into prm_umc_norm_to_addr(). It takes the GUID
and output buffer as parameters. Convert prm_umc_norm_to_sys_addr() into a
thin wrapper around it.

Rename the parameter buffer struct to param_buf. It is no longer specific
to the system physical address translation.

Include the error code in the log messages. This makes a failure easier to
diagnose.

This is in preparation for adding more PRM address translation handlers.

Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
---
 drivers/ras/amd/atl/internal.h |  2 ++
 drivers/ras/amd/atl/prm.c      | 35 +++++++++++++++++++++-------------
 2 files changed, 24 insertions(+), 13 deletions(-)

diff --git a/drivers/ras/amd/atl/internal.h b/drivers/ras/amd/atl/internal.h
index 4fc4bc3c3500..9f4d2a5b6c14 100644
--- a/drivers/ras/amd/atl/internal.h
+++ b/drivers/ras/amd/atl/internal.h
@@ -287,6 +287,8 @@ u64 remove_base_and_hole(struct addr_ctx *ctx, u64 addr);
 /* GUIDs for PRM handlers */
 extern const guid_t norm_to_sys_guid;
 
+int prm_umc_norm_to_addr(guid_t guid, u8 socket_id, u64 umc_bank_inst_id,
+			 unsigned long addr, void *out_buf);
 unsigned long prm_umc_norm_to_sys_addr(u8 socket_id, u64 umc_bank_inst_id, unsigned long addr);
 
 /*
diff --git a/drivers/ras/amd/atl/prm.c b/drivers/ras/amd/atl/prm.c
index eba9d104d09e..3d5a6f5ae0a9 100644
--- a/drivers/ras/amd/atl/prm.c
+++ b/drivers/ras/amd/atl/prm.c
@@ -18,36 +18,45 @@
 
 #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 {
+/* See "PRM Parameter Buffer" in the AMD ACPI Porting Guide. */
+struct param_buf {
 	u64 norm_addr;
 	u8 socket;
 	u64 bank_id;
 	void *out_buf;
 } __packed;
 
-unsigned long prm_umc_norm_to_sys_addr(u8 socket_id, u64 bank_id, unsigned long addr)
+int prm_umc_norm_to_addr(guid_t guid, u8 socket_id, u64 bank_id,
+			 unsigned long addr, void *out_buf)
 {
-	struct norm_to_sys_param_buf p_buf;
-	unsigned long ret_addr;
+	struct param_buf p_buf;
 	int ret;
 
 	p_buf.norm_addr = addr;
 	p_buf.socket    = socket_id;
 	p_buf.bank_id   = bank_id;
-	p_buf.out_buf   = &ret_addr;
+	p_buf.out_buf   = out_buf;
 
-	ret = acpi_call_prm_handler(norm_to_sys_guid, &p_buf);
+	ret = acpi_call_prm_handler(guid, &p_buf);
 	if (!ret)
-		return ret_addr;
+		return 0;
 
 	if (ret == -ENODEV || ret == -EOPNOTSUPP)
-		pr_debug("PRM module/handler not available\n");
+		pr_debug("PRM module/handler not available: %d\n", ret);
 	else
-		pr_notice_once("PRM address translation failed\n");
+		pr_notice_once("PRM address translation failed: %d\n", ret);
 
 	return ret;
 }
+
+unsigned long prm_umc_norm_to_sys_addr(u8 socket_id, u64 bank_id, unsigned long addr)
+{
+	unsigned long sys_addr;
+	int ret;
+
+	ret = prm_umc_norm_to_addr(norm_to_sys_guid, socket_id, bank_id, addr, &sys_addr);
+	if (ret)
+		return ret;
+
+	return sys_addr;
+}
-- 
2.53.0