[coreboot-gerrit] Change in coreboot[master]: lib/fmap: Cache FMAP in cbmem

[Philipp Deppenwiese (Code Review)]

Philipp Deppenwiese has submitted this change. ( https://review.coreboot.org/c/coreboot/+/35377 )

Change subject: lib/fmap: Cache FMAP in cbmem
......................................................................

lib/fmap: Cache FMAP in cbmem

For platform independend exposure of FMAP through a kernel module
cache the FMAP in CBMEM. In addition add a pointer in coreboot tables
pointing to the introduced CBMEM area.

To not waste the allocated DRAM, use the cached CBMEM in RAM enabled
stages if possible.

Tested on qemu using
https://github.com/9elements/linux/commits/google_firmware_fmap2

Tested on QEMU and Supermicro X11SSH-TF.

Change-Id: I4e01c573c3edfa34dbba5fe7604d4f6e18b584d5
Signed-off-by: Patrick Rudolph 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/35377
Tested-by: build bot (Jenkins) 
Reviewed-by: Aaron Durbin 
Reviewed-by: Arthur Heymans 
Reviewed-by: Julius Werner 
---
M src/commonlib/include/commonlib/cbmem_id.h
M src/commonlib/include/commonlib/coreboot_tables.h
M src/lib/coreboot_table.c
M src/lib/fmap.c
4 files changed, 68 insertions(+), 2 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Aaron Durbin: Looks good to me, approved
  Julius Werner: Looks good to me, approved
  Arthur Heymans: Looks good to me, approved

diff --git a/src/commonlib/include/commonlib/cbmem_id.h b/src/commonlib/include/commonlib/cbmem_id.h
index 8d0ca46..30bf88a 100644
--- a/src/commonlib/include/commonlib/cbmem_id.h
+++ b/src/commonlib/include/commonlib/cbmem_id.h
@@ -76,6 +76,7 @@
 #define CBMEM_ID_ROM1		0x524f4d31
 #define CBMEM_ID_ROM2		0x524f4d32
 #define CBMEM_ID_ROM3		0x524f4d33
+#define CBMEM_ID_FMAP		0x464d4150

#define CBMEM_ID_TO_NAME_TABLE				 \
    { CBMEM_ID_ACPI,		"ACPI       " }, \
@@ -134,5 +135,6 @@
    { CBMEM_ID_ROM0,		"VGA ROM #0 "}, \
    { CBMEM_ID_ROM1,		"VGA ROM #1 "}, \
    { CBMEM_ID_ROM2,		"VGA ROM #2 "}, \
-	{ CBMEM_ID_ROM3,		"VGA ROM #3 "},
+	{ CBMEM_ID_ROM3,		"VGA ROM #3 "}, \
+	{ CBMEM_ID_FMAP,		"FMAP       "},
 #endif /* _CBMEM_ID_H_ */
diff --git a/src/commonlib/include/commonlib/coreboot_tables.h b/src/commonlib/include/commonlib/coreboot_tables.h
index 7bded2a..6816670 100644
--- a/src/commonlib/include/commonlib/coreboot_tables.h
+++ b/src/commonlib/include/commonlib/coreboot_tables.h
@@ -89,6 +89,7 @@
    LB_TAG_VBOOT_WORKBUF		= 0x0034,
    LB_TAG_MMC_INFO			= 0x0035,
    LB_TAG_TCPA_LOG			= 0x0036,
+	LB_TAG_FMAP			= 0x0037,
    LB_TAG_CMOS_OPTION_TABLE	= 0x00c8,
    LB_TAG_OPTION			= 0x00c9,
    LB_TAG_OPTION_ENUM		= 0x00ca,
diff --git a/src/lib/coreboot_table.c b/src/lib/coreboot_table.c
index 66afcf3..9c5942f 100644
--- a/src/lib/coreboot_table.c
+++ b/src/lib/coreboot_table.c
@@ -345,7 +345,8 @@
    	{CBMEM_ID_ACPI_GNVS, LB_TAG_ACPI_GNVS},
    	{CBMEM_ID_VPD, LB_TAG_VPD},
    	{CBMEM_ID_WIFI_CALIBRATION, LB_TAG_WIFI_CALIBRATION},
-		{CBMEM_ID_TCPA_LOG, LB_TAG_TCPA_LOG}
+		{CBMEM_ID_TCPA_LOG, LB_TAG_TCPA_LOG},
+		{CBMEM_ID_FMAP, LB_TAG_FMAP},
    };
    int i;

diff --git a/src/lib/fmap.c b/src/lib/fmap.c
index 2b4e3ba..f007418 100644
--- a/src/lib/fmap.c
+++ b/src/lib/fmap.c
@@ -20,6 +20,7 @@
 #include <commonlib/fmap_serialized.h>
 #include <stddef.h>
 #include <string.h>
+#include <cbmem.h>

#include "fmap_config.h"

@@ -28,6 +29,7 @@
  */

static int fmap_print_once CAR_GLOBAL;
+static struct mem_region_device fmap_cache CAR_GLOBAL;

int find_fmap_directory(struct region_device *fmrd)
 {
@@ -36,6 +38,16 @@
    size_t fmap_size;
    size_t offset = FMAP_OFFSET;

+	if (cbmem_possibly_online() && !ENV_SMM) {
+		/* Try FMAP cache first */
+		const struct mem_region_device *cache;
+
+		cache = car_get_var_ptr(&fmap_cache);
+		if (region_device_sz(&cache->rdev))
+			return rdev_chain(fmrd, &cache->rdev, 0,
+					  region_device_sz(&cache->rdev));
+	}
+
    boot_device_init();
    boot = boot_device_ro();

@@ -195,3 +207,53 @@
    	return -1;
    return rdev_writeat(&rdev, buffer, 0, size);
 }
+
+static void fmap_register_cache(int unused)
+{
+	const struct cbmem_entry *e;
+	struct mem_region_device *mdev;
+
+	mdev = car_get_var_ptr(&fmap_cache);
+
+	/* Find the FMAP cache installed by previous stage */
+	e = cbmem_entry_find(CBMEM_ID_FMAP);
+	/* Don't set fmap_cache so that find_fmap_directory will use regular path */
+	if (!e)
+		return;
+
+	mem_region_device_ro_init(mdev, cbmem_entry_start(e), cbmem_entry_size(e));
+}
+
+/*
+ * The main reason to copy the FMAP into CBMEM is to make it available to the
+ * OS on every architecture. As side effect use the CBMEM copy as cache.
+ */
+static void fmap_setup_cache(int unused)
+{
+	struct region_device fmrd;
+
+	if (find_fmap_directory(&fmrd))
+		return;
+
+	/* Reloads the FMAP even on ACPI S3 resume */
+	const size_t s = region_device_sz(&fmrd);
+	struct fmap *fmap = cbmem_add(CBMEM_ID_FMAP, s);
+	if (!fmap) {
+		printk(BIOS_ERR, "ERROR: Failed to allocate CBMEM\n");
+		return;
+	}
+
+	const ssize_t ret = rdev_readat(&fmrd, fmap, 0, s);
+	if (ret != s) {
+		printk(BIOS_ERR, "ERROR: Failed to read FMAP into CBMEM\n");
+		cbmem_entry_remove(cbmem_entry_find(CBMEM_ID_FMAP));
+		return;
+	}
+
+	/* Finally advertise the cache for the current stage */
+	fmap_register_cache(unused);
+}
+
+ROMSTAGE_CBMEM_INIT_HOOK(fmap_setup_cache)
+RAMSTAGE_CBMEM_INIT_HOOK(fmap_register_cache)
+POSTCAR_CBMEM_INIT_HOOK(fmap_register_cache)