efi/cper, cxl: Decode CXL Error Log

Print the CXL Error Log field as found in CXL Protocol Error Section.

The CXL RAS Capability structure will be reused by OS First Handling
and the duplication/appropriate placement will be addressed eventually.
Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>

drivers/firmware/efi/cper_cxl.c

@@ -9,6 +9,7 @@
 
 #include <linux/cper.h>
 #include "cper_cxl.h"
+#include <linux/cxl_err.h>
 
 #define PROT_ERR_VALID_AGENT_TYPE		BIT_ULL(0)
 #define PROT_ERR_VALID_AGENT_ADDRESS		BIT_ULL(1)
@@ -16,6 +17,7 @@
 #define PROT_ERR_VALID_SERIAL_NUMBER		BIT_ULL(3)
 #define PROT_ERR_VALID_CAPABILITY		BIT_ULL(4)
 #define PROT_ERR_VALID_DVSEC			BIT_ULL(5)
+#define PROT_ERR_VALID_ERROR_LOG		BIT_ULL(6)
 
 static const char * const prot_err_agent_type_strs[] = {
 	"Restricted CXL Device",
@@ -149,4 +151,29 @@ void cper_print_prot_err(const char *pfx, const struct cper_sec_prot_err *prot_e
 		print_hex_dump(pfx, "", DUMP_PREFIX_OFFSET, 16, 4, (prot_err + 1),
 			       prot_err->dvsec_len, 0);
 	}
+
+	if (prot_err->valid_bits & PROT_ERR_VALID_ERROR_LOG) {
+		size_t size = sizeof(*prot_err) + prot_err->dvsec_len;
+		struct cxl_ras_capability_regs *cxl_ras;
+
+		pr_info("%s Error log length: 0x%04x\n", pfx, prot_err->err_len);
+
+		pr_info("%s CXL Error Log:\n", pfx);
+		cxl_ras = (struct cxl_ras_capability_regs *)((long)prot_err + size);
+		pr_info("%s cxl_ras_uncor_status: 0x%08x", pfx,
+			cxl_ras->uncor_status);
+		pr_info("%s cxl_ras_uncor_mask: 0x%08x\n", pfx,
+			cxl_ras->uncor_mask);
+		pr_info("%s cxl_ras_uncor_severity: 0x%08x\n", pfx,
+			cxl_ras->uncor_severity);
+		pr_info("%s cxl_ras_cor_status: 0x%08x", pfx,
+			cxl_ras->cor_status);
+		pr_info("%s cxl_ras_cor_mask: 0x%08x\n", pfx,
+			cxl_ras->cor_mask);
+		pr_info("%s cap_control: 0x%08x\n", pfx,
+			cxl_ras->cap_control);
+		pr_info("%s Header Log Registers:\n", pfx);
+		print_hex_dump(pfx, "", DUMP_PREFIX_OFFSET, 16, 4, cxl_ras->header_log,
+			       sizeof(cxl_ras->header_log), 0);
+	}
 }

include/linux/cxl_err.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2022 Advanced Micro Devices, Inc.
+ *
+ * Author: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
+ */
+
+#ifndef LINUX_CXL_ERR_H
+#define LINUX_CXL_ERR_H
+
+/* CXL RAS Capability Structure, CXL v3.1 sec 8.2.4.16 */
+struct cxl_ras_capability_regs {
+	u32 uncor_status;
+	u32 uncor_mask;
+	u32 uncor_severity;
+	u32 cor_status;
+	u32 cor_mask;
+	u32 cap_control;
+	u32 header_log[16];
+};
+
+#endif //__CXL_ERR_