[M] Change in coreboot[master]: drivers/ocp/ewl: Add EWL driver for EWL type 3 error handling

[Johnny Lin (Code Review)]

Attention is currently required from: Shelly Chang.

Hello Shelly Chang,

I'd like you to do a code review.
Please visit

https://review.coreboot.org/c/coreboot/+/69145

to review the following change.

Change subject: drivers/ocp/ewl: Add EWL driver for EWL type 3 error handling
......................................................................

drivers/ocp/ewl: Add EWL driver for EWL type 3 error handling

Add EWL (Enhanced Warning Log) driver which handles Intel EWL HOB
and prints EWL type 3 primarily associated with MRC training failures.

Change-Id: Ibd5b521bafd457505db4147c5d3fe41364a09045
Signed-off-by: Shelly Chang 
Signed-off-by: Johnny Lin 
---
A src/drivers/ocp/ewl/Kconfig
A src/drivers/ocp/ewl/Makefile.inc
A src/drivers/ocp/ewl/ewl.c
A src/drivers/ocp/ewl/ocp_ewl.h
4 files changed, 88 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/45/69145/1

diff --git a/src/drivers/ocp/ewl/Kconfig b/src/drivers/ocp/ewl/Kconfig
new file mode 100644
index 0000000..3c3b82d
--- /dev/null
+++ b/src/drivers/ocp/ewl/Kconfig
@@ -0,0 +1,5 @@
+config OCP_EWL
+	bool
+	default n
+	help
+	  It implements checking FSP Enhanced Warning Log Hob.
diff --git a/src/drivers/ocp/ewl/Makefile.inc b/src/drivers/ocp/ewl/Makefile.inc
new file mode 100644
index 0000000..43112e9
--- /dev/null
+++ b/src/drivers/ocp/ewl/Makefile.inc
@@ -0,0 +1 @@
+romstage-$(CONFIG_OCP_EWL) += ewl.c
diff --git a/src/drivers/ocp/ewl/ewl.c b/src/drivers/ocp/ewl/ewl.c
new file mode 100644
index 0000000..d70a23f
--- /dev/null
+++ b/src/drivers/ocp/ewl/ewl.c
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <soc/soc_util.h>
+#include <lib.h>
+#include "ocp_ewl.h"
+
+static void process_ewl_type3(EWL_ENTRY_HEADER *header, EWL_ENTRY_MEMORY_LOCATION memory_location)
+{
+	/* Treat warning as type 3, collect basic information and print to serial log */
+	EWL_ENTRY_TYPE3 *basic_warning;
+	basic_warning = (EWL_ENTRY_TYPE3 *)header;
+	printk(BIOS_ERR, "Major Warning Code = 0x%02x, Minor Warning Code = 0x%02x,\n",
+			basic_warning->Context.MajorWarningCode,
+			basic_warning->Context.MinorWarningCode);
+	printk(BIOS_ERR, "Major Checkpoint: 0x%02x\n", basic_warning->Context.MajorCheckpoint);
+	printk(BIOS_ERR, "Minor Checkpoint: 0x%02x\n", basic_warning->Context.MinorCheckpoint);
+
+	if (memory_location.Socket != 0xff)
+		printk(BIOS_ERR, "Socket %d\n", memory_location.Socket);
+	if (memory_location.Channel != 0xff)
+		printk(BIOS_ERR, "Channel %d\n", memory_location.Channel);
+	if (memory_location.Dimm != 0xff)
+		printk(BIOS_ERR, "Dimm %d\n", memory_location.Dimm);
+	if (memory_location.Rank != 0xff)
+		printk(BIOS_ERR, "Rank %d\n", memory_location.Rank);
+}
+
+void get_ewl(void)
+{
+	const EWL_PRIVATE_DATA *hob = get_ewl_hob();
+	int offset = 0;
+	bool type3_flag = 0;
+	EWL_ENTRY_HEADER *warning_header;
+	printk(BIOS_DEBUG, "Number of EWL entries %d\n", hob->numEntries);
+	while (offset < hob->status.Header.FreeOffset) {
+		warning_header = (EWL_ENTRY_HEADER *) &(hob->status.Buffer[offset]);
+		if (warning_header->Type == EwlType3) {
+			printk(BIOS_ERR, "EWL type: %d\n", warning_header->Type);
+			if (warning_header->Size != sizeof(EWL_ENTRY_TYPE3)) {
+				printk(BIOS_ERR, "EWL type3 size mismatch!\n");
+				return;
+			}
+			EWL_ENTRY_TYPE3 *type3;
+			type3 = (EWL_ENTRY_TYPE3 *)warning_header;
+			process_ewl_type3(warning_header, type3->MemoryLocation);
+			type3_flag = 1;
+		} else {
+			printk(BIOS_DEBUG, "EWL type: %d size:%d severity level:%d\n",
+					warning_header->Type,
+					warning_header->Size,
+					warning_header->Severity);
+			hexdump(&(hob->status.Buffer[offset]), warning_header->Size);
+		}
+		offset += warning_header->Size;
+	}
+	if (type3_flag)
+		die("Memory Training Error!\n");
+}
diff --git a/src/drivers/ocp/ewl/ocp_ewl.h b/src/drivers/ocp/ewl/ocp_ewl.h
new file mode 100644
index 0000000..38d5286d
--- /dev/null
+++ b/src/drivers/ocp/ewl/ocp_ewl.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef __OCP_EWL_H
+#define __OCP_EWL_H
+
+#include <soc/soc_util.h>
+
+void get_ewl(void);
+
+#endif