[coreboot-gerrit] Change in coreboot[master]: drivers/elog: Add support for early elog

[Karthik Ramasubramanian (Code Review)]

Karthik Ramasubramanian has uploaded this change for review. ( https://review.coreboot.org/29358

Change subject: drivers/elog: Add support for early elog
......................................................................

drivers/elog: Add support for early elog

Add support to log events during the romstage.

BUG=b:117884485

Change-Id: Ia69515961da3bc72740f9b048a53d91af79c5b0d
Signed-off-by: Karthikeyan Ramasubramanian 
---
M src/drivers/elog/Makefile.inc
M src/drivers/elog/elog.c
2 files changed, 37 insertions(+), 6 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/58/29358/1

diff --git a/src/drivers/elog/Makefile.inc b/src/drivers/elog/Makefile.inc
index 79a7cc0..e0c42e2 100644
--- a/src/drivers/elog/Makefile.inc
+++ b/src/drivers/elog/Makefile.inc
@@ -1,3 +1,4 @@
+romstage-$(CONFIG_ELOG) += elog.c
 ramstage-$(CONFIG_ELOG) += elog.c

smm-$(CONFIG_ELOG_GSMI) += elog.c gsmi.c
diff --git a/src/drivers/elog/elog.c b/src/drivers/elog/elog.c
index d3c01c2..7d0e0a9 100644
--- a/src/drivers/elog/elog.c
+++ b/src/drivers/elog/elog.c
@@ -16,6 +16,7 @@
 #if IS_ENABLED(CONFIG_HAVE_ACPI_RESUME)
 #include <arch/acpi.h>
 #endif
+#include <arch/early_variables.h>
 #include <bootstate.h>
 #include <cbmem.h>
 #include <console/console.h>
@@ -42,6 +43,15 @@
 #endif

#define NV_NEEDS_ERASE (~(size_t)0)
+enum elog_state {
+	ELOG_UNINITIALIZED = 0,
+	ELOG_INITIALIZED,
+	ELOG_BROKEN,
+};
+
+#define MAX_ELOG_SIZE (4 * KiB)
+
+#if ENV_RAMSTAGE
 /*
  * Static variables for ELOG state
  */
@@ -60,11 +70,29 @@
 /* Device that mirrors the eventlog in memory. */
 static struct mem_region_device mirror_dev;

-static enum {
-	ELOG_UNINITIALIZED = 0,
-	ELOG_INITIALIZED,
-	ELOG_BROKEN,
-} elog_initialized = ELOG_UNINITIALIZED;
+static enum elog_state elog_initialized;
+
+static uint8_t * get_elog_mirror_buffer(size_t elog_size) {
+	if (elog_size == MAX_ELOG_SIZE)
+		return (uint8_t *)malloc(elog_size);
+	return NULL;
+}
+#else
+static u16 full_threshold CAR_GLOBAL;
+static u16 shrink_size CAR_GLOBAL;
+static size_t mirror_last_write CAR_GLOBAL;
+static size_t nv_last_write CAR_GLOBAL;
+static struct region_device nv_dev CAR_GLOBAL;
+static struct mem_region_device mirror_dev CAR_GLOBAL;
+static enum elog_state elog_initialized CAR_GLOBAL;
+static uint8_t early_elog_buf[MAX_ELOG_SIZE] CAR_GLOBAL;
+
+static uint8_t * get_elog_mirror_buffer(size_t elog_size) {
+	if (elog_size == MAX_ELOG_SIZE)
+		return (uint8_t *)car_get_var_ptr(early_elog_buf);
+	return NULL;
+}
+#endif

static inline struct region_device *mirror_dev_get(void)
 {
@@ -776,7 +804,7 @@
    	return -1;

elog_size = region_device_sz(&nv_dev);
-	mirror_buffer = malloc(elog_size);
+	mirror_buffer = get_elog_mirror_buffer(elog_size);
    if (!mirror_buffer) {
    	printk(BIOS_ERR, "ELOG: Unable to allocate backing store\n");
    	return -1;
@@ -800,6 +828,7 @@
    	full_threshold, shrink_size);

if (elog_do_add_boot_count()) {
+#if ENV_RAMSTAGE
    	elog_add_event_dword(ELOG_TYPE_BOOT, boot_count_read());

#if IS_ENABLED(CONFIG_ARCH_X86)
@@ -807,6 +836,7 @@
    	if (IS_ENABLED(CONFIG_CMOS_POST))
    		cmos_post_log();
 #endif
+#endif /* ENV_RAMSTAGE */
    }
    return 0;
 }