Patch set updated for coreboot: d31f110 Extend CBFS to support arbitrary ROM source media.

[Hung-Te Lin]

Hung-Te Lin ([e-mail]) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/2182

-gerrit

commit d31f110aa0518ab3e101333a735f65f37b839e09
Author: Hung-Te Lin 
Date:   Tue Jan 22 18:57:56 2013 +0800

Extend CBFS to support arbitrary ROM source media.

Summary:
    	Isolate CBFS underlying I/O to board/arch-specific implementations as
    	"media stream", to allow loading and booting romstage on non-x86.

CBFS functions now all take a new "media source" parameter; use
    	CBFS_DEFAULT_MEDIA if you simply want to load from main firmware.
    	API Changes:
    		cbfs_find => cbfs_get_file.
    		cbfs_find_file => cbfs_get_file_content.
    		cbfs_get_file => cbfs_get_file_content with correct type.

CBFS used to work only on memory-mapped ROM (all x86). For platforms like ARM,
    the ROM may come from USB, UART, or SPI -- any serial devices and not available
    for memory mapping.

To support these devices (and allowing CBFS to read from multiple source
    at the same time), CBFS operations are now virtual-ized into "cbfs_media".  To
    simplify porting existing code, every media source must support both "reading
    into pre-allocated memory (read)" and "read and return an allocated buffer
    (map)". For devices without native memory-mapped ROM, "cbfs_simple_buffer*"
    provides simple memory mapping simulation.

Every CBFS function now takes a cbfs_media* as parameter. CBFS_DEFAULT_MEDIA
    is defined for CBFS functions to automatically initialize a per-board default
    media (CBFS will internally calls init_default_cbfs_media).  Also revised CBFS
    function names relying on memory mapped backend (ex, "cbfs_find" => actually
    loads files). Now we only have two getters:
    	struct cbfs_file *entry = cbfs_get_file(media, name);
    	void *data = cbfs_get_file_content(CBFS_DEFAULT_MEDIA, name, type);

Test results:
     - Verified to work on x86/qemu.
     - Compiles on ARM, and follow up commit will provide working SPI driver.

Change-Id: Iac911ded25a6f2feffbf3101a81364625bb07746
    Signed-off-by: Hung-Te Lin 
---
 src/arch/armv7/boot/coreboot_table.c               |   4 +-
 src/arch/armv7/bootblock_simple.c                  |   4 +-
 src/arch/armv7/include/arch/cbfs.h                 | 101 ++++-------
 src/arch/x86/boot/coreboot_table.c                 |   4 +-
 src/arch/x86/boot/smbios.c                         |  12 +-
 src/arch/x86/lib/Makefile.inc                      |   3 +
 src/arch/x86/lib/cbfs_and_run.c                    |   2 +-
 src/arch/x86/lib/rom_media.c                       | 101 +++++++++++
 src/cpu/intel/microcode/microcode.c                |   5 +-
 src/cpu/samsung/exynos5-common/Makefile.inc        |   4 +-
 src/cpu/samsung/exynos5-common/spi.c               |   7 +
 src/cpu/samsung/exynos5250/Kconfig                 |  16 ++
 src/cpu/via/nano/update_ucode.c                    |   2 +-
 src/device/oprom/realmode/x86.c                    |   8 +-
 src/device/oprom/yabel/vbe.c                       |   4 +-
 src/device/pci_rom.c                               |   9 +-
 src/drivers/pc80/mc146818rtc.c                     |   6 +-
 src/include/cbfs.h                                 |  37 +++-
 src/include/cbfs_core.h                            |  72 +++++---
 src/include/endian.h                               |  25 +++
 src/lib/cbfs.c                                     | 141 +++++++++++----
 src/lib/cbfs_core.c                                | 200 ++++++++++++---------
 src/lib/hardwaremain.c                             |   5 +-
 src/lib/selfboot.c                                 |   9 -
 src/mainboard/google/snow/bootblock.c              |   4 +
 src/mainboard/samsung/lumpy/romstage.c             |   2 +-
 .../amd/agesa/family15tn/fam15tn_callouts.c        |   4 +-
 src/northbridge/intel/i82830/vga.c                 |   2 +-
 src/northbridge/intel/sandybridge/raminit.c        |   4 +-
 29 files changed, 542 insertions(+), 255 deletions(-)

diff --git a/src/arch/armv7/boot/coreboot_table.c b/src/arch/armv7/boot/coreboot_table.c
index 86a004d..b2d88aa 100644
--- a/src/arch/armv7/boot/coreboot_table.c
+++ b/src/arch/armv7/boot/coreboot_table.c
@@ -640,7 +640,9 @@ unsigned long write_coreboot_table(

#if CONFIG_USE_OPTION_TABLE
    {
-		struct cmos_option_table *option_table = cbfs_find_file("cmos_layout.bin", 0x1aa);
+		struct cmos_option_table *option_table = cbfs_get_file_content(
+				CBFS_DEFAULT_MEDIA, "cmos_layout.bin",
+				CBFS_COMPONENT_CMOS_LAYOUT);
    	if (option_table) {
    		struct lb_record *rec_dest = lb_new_record(head);
    		/* Copy the option config table, it's already a lb_record... */
diff --git a/src/arch/armv7/bootblock_simple.c b/src/arch/armv7/bootblock_simple.c
index af76d4c..d97075e 100644
--- a/src/arch/armv7/bootblock_simple.c
+++ b/src/arch/armv7/bootblock_simple.c
@@ -45,7 +45,9 @@ void main(unsigned long bist)
    }

printk(BIOS_INFO, "bootblock main(): loading romstage\n");
-	romstage_entry = loadstage(target1);
+	romstage_entry = (unsigned long)cbfs_load_stage(
+			CBFS_DEFAULT_MEDIA, target1);
+
    printk(BIOS_INFO, "bootblock main(): jumping to romstage\n");
    if (romstage_entry) bootblock_exit(romstage_entry);
    hlt();
diff --git a/src/arch/armv7/include/arch/cbfs.h b/src/arch/armv7/include/arch/cbfs.h
index f060643..e34a0d2 100644
--- a/src/arch/armv7/include/arch/cbfs.h
+++ b/src/arch/armv7/include/arch/cbfs.h
@@ -20,82 +20,41 @@
 #ifndef __INCLUDE_ARCH_CBFS__
 #define __INCLUDE_ARCH_CBFS__

-#include <string.h>
-#include <types.h>
 #include <cbfs_core.h>
 #include <arch/byteorder.h>
-#include <arch/cbfs.h>

+// TODO FIXME This file is only for providing CBFS function in bootblock.
+// Should be removed once bootblock can link lib/* files.
+#include "lib/cbfs.c"

-static int cbfs_check_magic(struct cbfs_file *file)
-{
-	return strcmp(file->magic, CBFS_FILE_MAGIC) ? 0 : 1;
+// mem* and ulzma are now workarounds for bootblock compilation.
+void *memcpy(void *dest, const void *src, size_t n) {
+	char *d = (char *)dest;
+	const char *s = (const char*)src;
+	while (n-- > 0)
+		*d++ = *s++;
+	return dest;
 }

-static unsigned long loadstage(const char* target)
-{
-	unsigned long offset, align;
-	struct cbfs_header *header = (struct cbfs_header *)(CONFIG_BOOTBLOCK_BASE + 0x40);
-	/* FIXME: magic offsets */
-	// if (ntohl(header->magic) != CBFS_HEADER_MAGIC)
-	// 	printk(BIOS_ERR, "ERROR: No valid CBFS header found!\n");
+void *memset(void *dest, int c, size_t n) {
+	char *d = (char*)dest;
+	while (n-- > 0)
+		*d++ = c;
+	return dest;
+}
+
+int memcmp(const void *ptr1, const void *ptr2, size_t n) {
+	const char *s1 = (const char*)ptr1, *s2 = (const char*)ptr2;
+	int c;
+	while (n-- > 0)
+		if ((c = *s1++ - *s2++))
+			return c;
+	return 0;
+}

-	offset = ntohl(header->offset);
-	align = ntohl(header->align);
-	printk(BIOS_INFO, "cbfs header (0x%p)\n", header);
-	printk(BIOS_INFO, "\tmagic: 0x%08x\n", ntohl(header->magic));
-	printk(BIOS_INFO, "\tversion: 0x%08x\n", ntohl(header->version));
-	printk(BIOS_INFO, "\tromsize: 0x%08x\n", ntohl(header->romsize));
-	printk(BIOS_INFO, "\tbootblocksize: 0x%08x\n", ntohl(header->bootblocksize));
-	printk(BIOS_INFO, "\talign: 0x%08x\n", ntohl(header->align));
-	printk(BIOS_INFO, "\toffset: 0x%08x\n", ntohl(header->offset));
-	while(1) {
-		struct cbfs_file *file;
-		struct cbfs_stage *stage;
-		/* FIXME: SPI image hack */
-		file = (struct cbfs_file *)(offset + CONFIG_SPI_IMAGE_HACK);
-		if (!cbfs_check_magic(file)) {
-			printk(BIOS_INFO, "magic is wrong, file: %p\n", file);
-			return 0;
-		}
-		if (!strcmp(CBFS_NAME(file), target)) {
-			uint32_t  load, entry;
-			printk(BIOS_INFO, "CBFS name matched, offset: %p\n", file);
-			printk(BIOS_INFO, "\tmagic: %02x%02x%02x%02x%02x%02x%02x%02x\n",
-				file->magic[0], file->magic[1], file->magic[2], file->magic[3],
-				file->magic[4], file->magic[5], file->magic[6], file->magic[7]);
-			printk(BIOS_INFO, "\tlen: 0x%08x\n", ntohl(file->len));
-			printk(BIOS_INFO, "\ttype: 0x%08x\n", ntohl(file->type));
-			printk(BIOS_INFO, "\tchecksum: 0x%08x\n", ntohl(file->checksum));
-			printk(BIOS_INFO, "\toffset: 0x%08x\n", ntohl(file->offset));
-			/* exploit the fact that this is all word-aligned. */
-			stage = CBFS_SUBHEADER(file);
-			load = stage->load;
-			entry = stage->entry;
-			int i;
-			u32 *to = (void *)load;
-			u32 *from = (void *)((u8 *)stage+sizeof(*stage));
-			/* we could do memmove/memset here. But the math gets messy. 
-			 * far easier just to do what we want.
-			 */
-			 printk(BIOS_INFO, "entry: 0x%08x, load: 0x%08x, "
-			 	"len: 0x%08x, memlen: 0x%08x\n", entry,
-				 load, stage->len, stage->memlen);
-			for(i = 0; i < stage->len; i += 4)
-				*to++ = *from++;
-			for(; i < stage->memlen; i += 4)
-				*to++ = 0;
-			return entry;
-		}
-		int flen = ntohl(file->len);
-		int foffset = ntohl(file->offset);
-		unsigned long oldoffset = offset;
-		offset = ALIGN(offset + foffset + flen, align);
-		printk(BIOS_INFO, "offset: 0x%08lx\n", offset);
-		if (offset <= oldoffset)
-			return 0;
-		if (offset > CONFIG_ROMSTAGE_SIZE)
-			return 0;
-	}
+unsigned long ulzma(unsigned char *src, unsigned char *dest) {
+	// TODO remove this.
+	return -1;
 }
-#endif
+
+#endif // __INCLUDE_ARCH_CBFS__
diff --git a/src/arch/x86/boot/coreboot_table.c b/src/arch/x86/boot/coreboot_table.c
index 8dccd77..04fba47 100644
--- a/src/arch/x86/boot/coreboot_table.c
+++ b/src/arch/x86/boot/coreboot_table.c
@@ -638,7 +638,9 @@ unsigned long write_coreboot_table(

#if CONFIG_USE_OPTION_TABLE
    {
-		struct cmos_option_table *option_table = cbfs_find_file("cmos_layout.bin", 0x1aa);
+		struct cmos_option_table *option_table = cbfs_get_file_content(
+				CBFS_DEFAULT_MEDIA, "cmos_layout.bin",
+				CBFS_COMPONENT_CMOS_LAYOUT);
    	if (option_table) {
    		struct lb_record *rec_dest = lb_new_record(head);
    		/* Copy the option config table, it's already a lb_record... */
diff --git a/src/arch/x86/boot/smbios.c b/src/arch/x86/boot/smbios.c
index 72e70ba..f65ced2 100644
--- a/src/arch/x86/boot/smbios.c
+++ b/src/arch/x86/boot/smbios.c
@@ -120,7 +120,6 @@ static int smbios_processor_name(char *start)

static int smbios_write_type0(unsigned long *current, int handle)
 {
-	struct cbfs_header *hdr;
    struct smbios_type0 *t = (struct smbios_type0 *)*current;
    int len = sizeof(struct smbios_type0);

@@ -143,8 +142,15 @@ static int smbios_write_type0(unsigned long *current, int handle)
    vboot_data->vbt10 = (u32)t->eos + (version_offset - 1);
 #endif

-	if ((hdr = get_cbfs_header()) != (struct cbfs_header *)0xffffffff)
-		t->bios_rom_size = (ntohl(hdr->romsize) / 65535) - 1;
+	{
+		const struct cbfs_header *header;
+		u32 romsize = CONFIG_ROM_SIZE;
+		header = cbfs_get_header(CBFS_DEFAULT_MEDIA);
+		if (header != CBFS_HEADER_INVALID_ADDRESS)
+			romsize = ntohl(header->romsize);
+		t->bios_rom_size = (romsize / 65535) - 1;
+	}
+
    t->system_bios_major_release = 4;
    t->bios_characteristics =
    	BIOS_CHARACTERISTICS_PCI_SUPPORTED |
diff --git a/src/arch/x86/lib/Makefile.inc b/src/arch/x86/lib/Makefile.inc
index 2186072..f4dc8b8 100644
--- a/src/arch/x86/lib/Makefile.inc
+++ b/src/arch/x86/lib/Makefile.inc
@@ -8,13 +8,16 @@ ramstage-$(CONFIG_IOAPIC) += ioapic.c
 ramstage-y += memset.c
 ramstage-y += memcpy.c
 ramstage-y += ebda.c
+ramstage-y += rom_media.c

romstage-y += romstage_console.c
 romstage-y += cbfs_and_run.c
 romstage-y += memset.c
 romstage-y += memcpy.c
+romstage-y += rom_media.c

smm-y += memset.c
 smm-y += memcpy.c
+smm-y += rom_media.c

$(obj)/arch/x86/lib/console.ramstage.o :: $(obj)/build.h
diff --git a/src/arch/x86/lib/cbfs_and_run.c b/src/arch/x86/lib/cbfs_and_run.c
index 1f87e7a..a023141 100644
--- a/src/arch/x86/lib/cbfs_and_run.c
+++ b/src/arch/x86/lib/cbfs_and_run.c
@@ -28,7 +28,7 @@ static void cbfs_and_run_core(const char *filename, unsigned ebp)

timestamp_add_now(TS_START_COPYRAM);
    print_debug("Loading image.\n");
-	dst = cbfs_load_stage(filename);
+	dst = cbfs_load_stage(CBFS_DEFAULT_MEDIA, filename);
    if ((void *)dst == (void *) -1)
    	die("FATAL: Essential component is missing.\n");

diff --git a/src/arch/x86/lib/rom_media.c b/src/arch/x86/lib/rom_media.c
new file mode 100644
index 0000000..ed2122c
--- /dev/null
+++ b/src/arch/x86/lib/rom_media.c
@@ -0,0 +1,101 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; version 2 of
+ * the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
+ * MA 02110-1301 USA
+ */
+#include <cbfs.h>
+#include <string.h>
+
+#ifdef LIBPAYLOAD
+# define printk(x...)
+# define init_default_cbfs_media libpayload_init_default_cbfs_media
+  extern int libpayload_init_default_cbfs_media(struct cbfs_media *media);
+#else
+# include <console/console.h>
+#endif
+
+// Implementation of memory-mapped ROM media source on X86.
+
+static int x86_rom_open(struct cbfs_media *media) {
+	return 0;
+}
+
+static void *x86_rom_map(struct cbfs_media *media, size_t offset, size_t count) {
+	void *ptr;
+	// Some address (ex, pointer to master header) may be given in memory
+	// mapped location. To workaround that, we handle >0xf0000000 as real
+	// memory pointer.
+
+	if ((uint32_t)offset > (uint32_t)0xf0000000)
+		ptr = (void*)offset;
+	else
+		ptr = (void*)(0 - (uint32_t)media->context + offset);
+	return ptr;
+}
+
+static void *x86_rom_unmap(struct cbfs_media *media, const void *address) {
+	return NULL;
+}
+
+static size_t x86_rom_read(struct cbfs_media *media, void *dest, size_t offset,
+			   size_t count) {
+	void *ptr = x86_rom_map(media, offset, count);
+	memcpy(dest, ptr, count);
+	x86_rom_unmap(media, ptr);
+	return count;
+}
+
+static int x86_rom_close(struct cbfs_media *media) {
+	return 0;
+}
+
+int init_x86rom_cbfs_media(struct cbfs_media *media);
+int init_x86rom_cbfs_media(struct cbfs_media *media) {
+	// On X86, we always keep a reference of pointer to CBFS header in
+	// 0xfffffffc, and the pointer is still a memory-mapped address.
+	// Since the CBFS core always use ROM offset, we need to figure out
+	// header->romsize even before media is initialized.
+	struct cbfs_header *header = (struct cbfs_header*)
+			*(uint32_t*)(0xfffffffc);
+	if (CBFS_HEADER_MAGIC != ntohl(header->magic)) {
+#if defined(CONFIG_ROM_SIZE)
+		printk(BIOS_ERR, "Invalid CBFS master header at %p\n", header);
+		media->context = (void*)CONFIG_ROM_SIZE;
+#else
+		return -1;
+#endif
+	} else {
+		uint32_t romsize = ntohl(header->romsize);
+		media->context = (void*)romsize;
+#if defined(CONFIG_ROM_SIZE)
+		if (CONFIG_ROM_SIZE != romsize)
+			printk(BIOS_INFO, "Warning: rom size unmatch (%d/%d)\n",
+			       CONFIG_ROM_SIZE, romsize);
+#endif
+	}
+	media->open = x86_rom_open;
+	media->close = x86_rom_close;
+	media->map = x86_rom_map;
+	media->unmap = x86_rom_unmap;
+	media->read = x86_rom_read;
+	return 0;
+}
+
+int init_default_cbfs_media(struct cbfs_media *media) {
+	return init_x86rom_cbfs_media(media);
+}
diff --git a/src/cpu/intel/microcode/microcode.c b/src/cpu/intel/microcode/microcode.c
index 15d6513..713a6df 100644
--- a/src/cpu/intel/microcode/microcode.c
+++ b/src/cpu/intel/microcode/microcode.c
@@ -166,8 +166,9 @@ void intel_update_microcode_from_cbfs(void)
 #ifdef __PRE_RAM__
    microcode_blob = walkcbfs((char *) MICROCODE_CBFS_FILE);
 #else
-	microcode_blob = cbfs_find_file(MICROCODE_CBFS_FILE,
-					CBFS_TYPE_MICROCODE);
+	microcode_blob = cbfs_get_file_content(CBFS_DEFAULT_MEDIA,
+					       MICROCODE_CBFS_FILE,
+					       CBFS_TYPE_MICROCODE);
 #endif
    intel_update_microcode(microcode_blob);
 }
diff --git a/src/cpu/samsung/exynos5-common/Makefile.inc b/src/cpu/samsung/exynos5-common/Makefile.inc
index cad6cb3..d919347 100644
--- a/src/cpu/samsung/exynos5-common/Makefile.inc
+++ b/src/cpu/samsung/exynos5-common/Makefile.inc
@@ -1,2 +1,2 @@
-#romstage-y += soc.c
-romstage-y += spl_boot.c
+romstage-y += spi.c
+ramstage-y += spi.c
diff --git a/src/cpu/samsung/exynos5-common/spi.c b/src/cpu/samsung/exynos5-common/spi.c
new file mode 100644
index 0000000..e13eadf
--- /dev/null
+++ b/src/cpu/samsung/exynos5-common/spi.c
@@ -0,0 +1,7 @@
+#include <cbfs.h>
+
+/* TODO provide a real SPI driver here for firmware media. */
+
+int init_default_cbfs_media(struct cbfs_media *media) {
+	return -1;
+}
diff --git a/src/cpu/samsung/exynos5250/Kconfig b/src/cpu/samsung/exynos5250/Kconfig
index f5beddc..41a1446 100644
--- a/src/cpu/samsung/exynos5250/Kconfig
+++ b/src/cpu/samsung/exynos5250/Kconfig
@@ -48,6 +48,22 @@ config ROMSTAGE_SIZE
    hex
    default 0x10000

+# TODO Change this to some better address not overlapping bootblock when
+# cbfstool supports creating header in arbitrary location.
+config CBFS_HEADER_ROM_OFFSET
+	hex "offset of master CBFS header in ROM"
+	default 0x2040
+
+# TODO We may probably move this to board-specific implementation files instead
+# of KConfig values.
+config CBFS_CACHE_ADDRESS
+	hex "memory address to put CBFS cache data"
+	default 0x02060000
+
+config CBFS_CACHE_SIZE
+	hex "size of CBFS cache data"
+	default 0x000017000
+
 # FIXME: This is for copying SPI content into SRAM temporarily and
 # will be removed when we have the SPI streaming driver implemented.
 config SPI_IMAGE_HACK
diff --git a/src/cpu/via/nano/update_ucode.c b/src/cpu/via/nano/update_ucode.c
index 8f7ee22..d5757f8 100644
--- a/src/cpu/via/nano/update_ucode.c
+++ b/src/cpu/via/nano/update_ucode.c
@@ -105,7 +105,7 @@ unsigned int nano_update_ucode(void)
    const struct cbfs_file *cbfs_ucode;
    u32 fms = cpuid_eax(0x1);

-	cbfs_ucode = cbfs_find("cpu_microcode_blob.bin");
+	cbfs_ucode = cbfs_get_file(CBFS_DEFAULT_MEDIA, "cpu_microcode_blob.bin");
    /* Oops, did you forget to include the microcode ? */
    if(cbfs_ucode == NULL) {
    	printk(BIOS_ALERT, "WARNING: No microcode file found in CBFS. "
diff --git a/src/device/oprom/realmode/x86.c b/src/device/oprom/realmode/x86.c
index 697d869..07eff0d 100644
--- a/src/device/oprom/realmode/x86.c
+++ b/src/device/oprom/realmode/x86.c
@@ -248,8 +248,9 @@ void vbe_set_graphics(void)
 #if CONFIG_BOOTSPLASH
    struct jpeg_decdata *decdata;
    decdata = malloc(sizeof(*decdata));
-	unsigned char *jpeg = cbfs_find_file("bootsplash.jpg",
-						CBFS_TYPE_BOOTSPLASH);
+	unsigned char *jpeg = cbfs_get_file_content(CBFS_DEFAULT_MEDIA,
+						    "bootsplash.jpg",
+						    CBFS_TYPE_BOOTSPLASH);
    if (!jpeg) {
    	printk(BIOS_DEBUG, "VBE: No bootsplash found.\n");
    	return;
@@ -366,7 +367,8 @@ void do_vsmbios(void)
    printk(BIOS_SPEW, "VSA: Real mode stub @%p: %d bytes\n", REALMODE_BASE,
    		(u32)&__realmode_code_size);

-	if ((unsigned int)cbfs_load_stage("vsa") != VSA2_ENTRY_POINT) {
+	if ((unsigned int)cbfs_load_stage(CBFS_DEFAULT_MEDIA, "vsa") !=
+	    VSA2_ENTRY_POINT) {
    	printk(BIOS_ERR, "Failed to load VSA.\n");
    	return;
    }
diff --git a/src/device/oprom/yabel/vbe.c b/src/device/oprom/yabel/vbe.c
index 9dbe07c..5952dae 100644
--- a/src/device/oprom/yabel/vbe.c
+++ b/src/device/oprom/yabel/vbe.c
@@ -725,7 +725,9 @@ void vbe_set_graphics(void)
     * cares. */
    // int imagesize = 1024*768*2;

-	unsigned char *jpeg = cbfs_find_file("bootsplash.jpg", CBFS_TYPE_BOOTSPLASH);
+	unsigned char *jpeg = cbfs_get_file_content(CBFS_DEFAULT_MEDIA,
+						    "bootsplash.jpg",
+						    CBFS_TYPE_BOOTSPLASH);
    if (!jpeg) {
    	DEBUG_PRINTF_VBE("Could not find bootsplash.jpg\n");
    	return;
diff --git a/src/device/pci_rom.c b/src/device/pci_rom.c
index fe67515..bb0d760 100644
--- a/src/device/pci_rom.c
+++ b/src/device/pci_rom.c
@@ -35,7 +35,8 @@ struct rom_header *pci_rom_probe(struct device *dev)
    struct pci_data *rom_data;

/* If it's in FLASH, then don't check device for ROM. */
-	rom_header = cbfs_load_optionrom(dev->vendor, dev->device, NULL);
+	rom_header = cbfs_load_optionrom(CBFS_DEFAULT_MEDIA, dev->vendor,
+					 dev->device, NULL);

u32 vendev = (dev->vendor << 16) | dev->device;
    u32 mapped_vendev = vendev;
@@ -45,8 +46,10 @@ struct rom_header *pci_rom_probe(struct device *dev)

if (!rom_header) {
    	if (vendev != mapped_vendev) {
-			rom_header = cbfs_load_optionrom(mapped_vendev >> 16,
-					mapped_vendev & 0xffff , NULL);
+			rom_header = cbfs_load_optionrom(
+					CBFS_DEFAULT_MEDIA,
+					mapped_vendev >> 16,
+					mapped_vendev & 0xffff, NULL);
    	}
    }

diff --git a/src/drivers/pc80/mc146818rtc.c b/src/drivers/pc80/mc146818rtc.c
index d8d1778..5ffa9d7 100644
--- a/src/drivers/pc80/mc146818rtc.c
+++ b/src/drivers/pc80/mc146818rtc.c
@@ -190,7 +190,8 @@ int get_option(void *dest, const char *name)
    namelen = strnlen(name, CMOS_MAX_NAME_LENGTH);

/* find the requested entry record */
-	ct=cbfs_find_file("cmos_layout.bin", CBFS_COMPONENT_CMOS_LAYOUT);
+	ct = cbfs_get_file_content(CBFS_DEFAULT_MEDIA, "cmos_layout.bin",
+				   CBFS_COMPONENT_CMOS_LAYOUT);
    if (!ct) {
    	printk(BIOS_ERR, "RTC: cmos_layout.bin could not be found. "
    					"Options are disabled\n");
@@ -268,7 +269,8 @@ int set_option(const char *name, void *value)
    namelen = strnlen(name, CMOS_MAX_NAME_LENGTH);

/* find the requested entry record */
-	ct=cbfs_find_file("cmos_layout.bin", CBFS_COMPONENT_CMOS_LAYOUT);
+	ct = cbfs_get_file_content(CBFS_DEFAULT_MEDIA, "cmos_layout.bin",
+				   CBFS_COMPONENT_CMOS_LAYOUT);
    if (!ct) {
    	printk(BIOS_ERR, "cmos_layout.bin could not be found. Options are disabled\n");
    	return(-2);
diff --git a/src/include/cbfs.h b/src/include/cbfs.h
index b33e932..9bfe2ce 100644
--- a/src/include/cbfs.h
+++ b/src/include/cbfs.h
@@ -2,6 +2,7 @@
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2008 Jordan Crouse 
+ * Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
  *
  * This file is dual-licensed. You can choose between:
  *   - The GNU GPL, version 2, as published by the Free Software Foundation
@@ -49,14 +50,38 @@
 #ifndef _CBFS_H_
 #define _CBFS_H_

-#include "cbfs_core.h"
-#include <boot/coreboot_tables.h>
+#include <cbfs_core.h>

-void *cbfs_load_payload(struct lb_memory *lb_mem, const char *name);
-void *cbfs_load_stage(const char *name);
-int cbfs_execute_stage(const char *name);
-void *cbfs_load_optionrom(u16 vendor, u16 device, void * dest);
+int cbfs_execute_stage(struct cbfs_media *media, const char *name);
+void *cbfs_load_optionrom(struct cbfs_media *media, uint16_t vendor,
+			  uint16_t device, void * dest);
+void *cbfs_load_payload(struct cbfs_media *media, const char *name);
+void *cbfs_load_stage(struct cbfs_media *media, const char *name);
+
+/* Simple buffer for streaming media. */
+struct cbfs_simple_buffer {
+	char *buffer;
+	size_t allocated;
+	size_t size;
+	size_t last_allocate;
+};
+
+void *cbfs_simple_buffer_map(struct cbfs_simple_buffer *buffer,
+			     struct cbfs_media *media,
+			     size_t offset, size_t count);
+
+void *cbfs_simple_buffer_unmap(struct cbfs_simple_buffer *buffer,
+			       const void *address);
+
+// Utility functions
 int run_address(void *f);
+
+/* Defined in src/lib/selfboot.c */
+struct lb_memory;
 int selfboot(struct lb_memory *mem, struct cbfs_payload *payload);
+
+/* Defined in individual arch / board implementation. */
+int init_default_cbfs_media(struct cbfs_media *media);
+
 #endif

diff --git a/src/include/cbfs_core.h b/src/include/cbfs_core.h
index a3c54b1..20636e2 100644
--- a/src/include/cbfs_core.h
+++ b/src/include/cbfs_core.h
@@ -3,6 +3,7 @@
  *
  * Copyright (C) 2008 Jordan Crouse 
  * Copyright (C) 2012 Google, Inc.
+ * Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
  *
  * This file is dual-licensed. You can choose between:
  *   - The GNU GPL, version 2, as published by the Free Software Foundation
@@ -50,6 +51,10 @@
 #ifndef _CBFS_CORE_H_
 #define _CBFS_CORE_H_

+#include <endian.h>
+#include <stddef.h>
+#include <stdint.h>
+
 /** These are standard values for the known compression
     alogrithms that coreboot knows about for stages and
     payloads.  Of course, other CBFS users can use whatever
@@ -74,24 +79,18 @@
 #define CBFS_COMPONENT_CMOS_DEFAULT 0xaa
 #define CBFS_COMPONENT_CMOS_LAYOUT 0x01aa

-
-/** this is the master cbfs header - it need to be
-    located somewhere in the bootblock.  Where it
-    actually lives is up to coreboot. On x86, a
-    pointer to this header will live at 0xFFFFFFFC,
-    so we can easily find it. */
-
 #define CBFS_HEADER_MAGIC  0x4F524243
-#if CONFIG_ARCH_X86
-#define CBFS_HEADPTR_ADDR 0xFFFFFFFC
-#elif CONFIG_ARCH_ARMV7
-/* FIXME: This could also be 0xFFFF0000 with HIVECS enabled */
-#define CBFS_HEADPTR_ADDR 0x0000000C
-#endif
 #define CBFS_HEADER_VERSION1 0x31313131
 #define CBFS_HEADER_VERSION2 0x31313132
 #define CBFS_HEADER_VERSION  CBFS_HEADER_VERSION2

+#define CBFS_HEADER_INVALID_ADDRESS	((void*)(0xffffffff))
+
+/** this is the master cbfs header - it need to be located somewhere available
+    to bootblock (to load romstage).  Where it actually lives is up to coreboot.
+    On x86, a pointer to this header will live at 0xFFFFFFFC.
+    For other platforms, you need to define CONFIG_CBFS_HEADER_ROM_OFFSET */
+
 struct cbfs_header {
    uint32_t magic;
    uint32_t version;
@@ -181,16 +180,49 @@ struct cbfs_optionrom {
 #define CBFS_NAME(_c) (((char *) (_c)) + sizeof(struct cbfs_file))
 #define CBFS_SUBHEADER(_p) ( (void *) ((((uint8_t *) (_p)) + ntohl((_p)->offset))) )

-/* returns pointer to file inside CBFS or NULL */
-struct cbfs_file *cbfs_find(const char *name);
+#define CBFS_MEDIA_INVALID_MAP_ADDRESS	((void*)(0xffffffff))
+#define CBFS_DEFAULT_MEDIA		((void*)(0x0))
+
+/* Media for CBFS to load files. */
+struct cbfs_media {
+
+	/* implementation dependent context, to hold resource references */
+	void *context;

-/* returns pointer to file data inside CBFS */
-void *cbfs_get_file(const char *name);
+	/* opens media and returns 0 on success, -1 on failure */
+	int (*open)(struct cbfs_media *media);

-/* returns pointer to file data inside CBFS after if type is correct */
-void *cbfs_find_file(const char *name, int type);
+	/* returns number of bytes read from media into dest, starting from
+	 * offset for count of bytes */
+	size_t (*read)(struct cbfs_media *media, void *dest, size_t offset,
+		       size_t count);
+
+	/* returns a pointer to memory with count of bytes from media source
+	 * starting from offset, or CBFS_MEDIA_INVALID_MAP_ADDRESS on failure.
+	 * Note: mapped data can't be free unless unmap is called, even if you
+	 * do close first. */
+	void * (*map)(struct cbfs_media *media, size_t offset, size_t count);
+
+	/* returns NULL and releases the memory by address, which was allocated
+	 * by map */
+	void * (*unmap)(struct cbfs_media *media, const void *address);
+
+	/* closes media and returns 0 on success, -1 on failure. */
+	int (*close)(struct cbfs_media *media);
+};
+
+/* returns pointer to a file entry inside CBFS or NULL */
+struct cbfs_file *cbfs_get_file(struct cbfs_media *media, const char *name);
+
+/* returns pointer to file content inside CBFS after if type is correct */
+void *cbfs_get_file_content(struct cbfs_media *media, const char *name,
+			    int type);

/* returns 0 on success, -1 on failure */
 int cbfs_decompress(int algo, void *src, void *dst, int len);
-struct cbfs_header *get_cbfs_header(void);
+
+/* returns a pointer to CBFS master header, or CBFS_HEADER_INVALID_ADDRESS
+ *  on failure */
+const struct cbfs_header *cbfs_get_header(struct cbfs_media *media);
+
 #endif
diff --git a/src/include/endian.h b/src/include/endian.h
new file mode 100644
index 0000000..b511a49
--- /dev/null
+++ b/src/include/endian.h
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but without any warranty; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _ENDIAN_H_
+#define _ENDIAN_H_
+
+#include <arch/byteorder.h>
+
+#endif
diff --git a/src/lib/cbfs.c b/src/lib/cbfs.c
index 98672d4..3e44582 100644
--- a/src/lib/cbfs.c
+++ b/src/lib/cbfs.c
@@ -2,6 +2,7 @@
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2008, Jordan Crouse 
+ * Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -17,57 +18,74 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
  */

-#include <types.h>
-#include <string.h>
-#include <console/console.h>
+#ifdef LIBPAYLOAD
+# include <libpayload-config.h>
+# ifdef CONFIG_LZMA
+#  include <lzma.h>
+#  define CBFS_CORE_WITH_LZMA
+# endif
+# define CBFS_MINI_BUILD
+#elif defined(__SMM__)
+# define CBFS_MINI_BUILD
+#else
+# define CBFS_CORE_WITH_LZMA
+# include <lib.h>
+#endif
+
 #include <cbfs.h>
-#include <lib.h>
-#include <arch/byteorder.h>
+#include <string.h>

-// use CBFS core
-#ifndef __SMM__
-#define CBFS_CORE_WITH_LZMA
+#ifdef LIBPAYLOAD
+# include <stdio.h>
+# define DEBUG(x...)
+# define LOG(x...) printf(x)
+# define ERROR(x...) printf(x)
+#else
+# include <console/console.h>
+# define ERROR(x...) printk(BIOS_ERR, "CBFS: " x)
+# define LOG(x...) printk(BIOS_INFO, "CBFS: " x)
+# if CONFIG_DEBUG_CBFS
+#  define DEBUG(x...) printk(BIOS_SPEW, "CBFS: " x)
+# else
+#  define DEBUG(x...)
+# endif
 #endif
-#define phys_to_virt(x) (void*)(x)
-#define virt_to_phys(x) (uint32_t)(x)
-#define ERROR(x...) printk(BIOS_ERR, "CBFS: " x)
-#define LOG(x...) printk(BIOS_INFO, "CBFS: " x)
-#if CONFIG_DEBUG_CBFS
-#define DEBUG(x...) printk(BIOS_SPEW, "CBFS: " x)
+
+#if defined(CONFIG_CBFS_HEADER_ROM_OFFSET) && (CONFIG_CBFS_HEADER_ROM_OFFSET)
+# define CBFS_HEADER_ROM_ADDRESS (CONFIG_CBFS_HEADER_ROM_OFFSET)
 #else
-#define DEBUG(x...)
+// Indirect address: only works on 32bit top-aligned systems.
+# define CBFS_HEADER_ROM_ADDRESS (*(uint32_t *)0xfffffffc)
 #endif
-// FIXME: romstart/romend are fine on x86, but not on ARM
-#define romstart() 0xffffffff
-#define romend() 0

#include "cbfs_core.c"

#ifndef __SMM__
 static inline int tohex4(unsigned int c)
 {
-	return (c<=9)?(c+'0'):(c-10+'a');
+	return (c <= 9) ? (c + '0') : (c - 10 + 'a');
 }

static void tohex16(unsigned int val, char* dest)
 {
-	dest[0]=tohex4(val>>12);
-	dest[1]=tohex4((val>>8) & 0xf);
-	dest[2]=tohex4((val>>4) & 0xf);
-	dest[3]=tohex4(val & 0xf);
+	dest[0] = tohex4(val>>12);
+	dest[1] = tohex4((val>>8) & 0xf);
+	dest[2] = tohex4((val>>4) & 0xf);
+	dest[3] = tohex4(val & 0xf);
 }

-void *cbfs_load_optionrom(u16 vendor, u16 device, void * dest)
+void *cbfs_load_optionrom(struct cbfs_media *media, uint16_t vendor,
+			  uint16_t device, void *dest)
 {
-	char name[17]="pciXXXX,XXXX.rom";
+	char name[17] = "pciXXXX,XXXX.rom";
    struct cbfs_optionrom *orom;
-	u8 *src;
+	uint8_t *src;

tohex16(vendor, name+3);
    tohex16(device, name+8);

orom = (struct cbfs_optionrom *)
-		cbfs_find_file(name, CBFS_TYPE_OPTIONROM);
+		cbfs_get_file_content(media, name, CBFS_TYPE_OPTIONROM);

if (orom == NULL)
    	return NULL;
@@ -77,10 +95,10 @@ void *cbfs_load_optionrom(u16 vendor, u16 device, void * dest)
     * in the common case, the expansion rom is uncompressed, we
     * pass 0 in for the dest, and all we have to do is find the rom and
     * return a pointer to it.
- 	 */
+	 */

/* BUG: the cbfstool is (not yet) including a cbfs_optionrom header */
-	src = ((unsigned char *) orom); // + sizeof(struct cbfs_optionrom);
+	src = (uint8_t *)orom; // + sizeof(struct cbfs_optionrom);

if (! dest)
    	return src;
@@ -94,27 +112,27 @@ void *cbfs_load_optionrom(u16 vendor, u16 device, void * dest)
    return dest;
 }

-void * cbfs_load_stage(const char *name)
+void * cbfs_load_stage(struct cbfs_media *media, const char *name)
 {
    struct cbfs_stage *stage = (struct cbfs_stage *)
-		cbfs_find_file(name, CBFS_TYPE_STAGE);
+		cbfs_get_file_content(media, name, CBFS_TYPE_STAGE);
    /* this is a mess. There is no ntohll. */
    /* for now, assume compatible byte order until we solve this. */
-	u32 entry;
+	uint32_t entry;

if (stage == NULL)
    	return (void *) -1;

LOG("loading stage %s @ 0x%x (%d bytes), entry @ 0x%llx\n",
    		name,
-			(u32) stage->load, stage->memlen,
+			(uint32_t) stage->load, stage->memlen,
    		stage->entry);
-	memset((void *) (u32) stage->load, 0, stage->memlen);
+	memset((void *) (uint32_t) stage->load, 0, stage->memlen);

if (cbfs_decompress(stage->compression,
    		     ((unsigned char *) stage) +
    		     sizeof(struct cbfs_stage),
-			     (void *) (u32) stage->load,
+			     (void *) (uint32_t) stage->load,
    		     stage->len))
    	return (void *) -1;

@@ -126,10 +144,10 @@ void * cbfs_load_stage(const char *name)
    return (void *) entry;
 }

-int cbfs_execute_stage(const char *name)
+int cbfs_execute_stage(struct cbfs_media *media, const char *name)
 {
    struct cbfs_stage *stage = (struct cbfs_stage *)
-		cbfs_find_file(name, CBFS_TYPE_STAGE);
+		cbfs_get_file_content(media, name, CBFS_TYPE_STAGE);

if (stage == NULL)
    	return 1;
@@ -141,8 +159,52 @@ int cbfs_execute_stage(const char *name)
    }

/* FIXME: This isn't right */
-	LOG("run @ %p\n", (void *) ntohl((u32) stage->entry));
-	return run_address((void *) (intptr_t)ntohll(stage->entry));
+	LOG("run @ %p\n", (void *) ntohl((uint32_t) stage->entry));
+	return run_address((void *)(uintptr_t)ntohll(stage->entry));
+}
+
+void *cbfs_load_payload(struct cbfs_media *media, const char *name)
+{
+	return (struct cbfs_payload *)cbfs_get_file_content(
+			media, name, CBFS_TYPE_PAYLOAD);
+}
+
+/* Simple buffer */
+
+void *cbfs_simple_buffer_map(struct cbfs_simple_buffer *buffer,
+			     struct cbfs_media *media,
+			     size_t offset, size_t count) {
+	void *address = buffer->buffer + buffer->allocated;;
+	DEBUG("simple_buffer_map(offset=%d, count=%d): "
+	      "allocated=%d, size=%d, last_allocate=%d\n",
+	    offset, count, buffer->allocated, buffer->size,
+	    buffer->last_allocate);
+	if (buffer->allocated + count >= buffer->size)
+		return CBFS_MEDIA_INVALID_MAP_ADDRESS;
+	if (media->read(media, address, offset, count) != count) {
+		ERROR("simple_buffer: fail to read %zd bytes from 0x%zx\n",
+		      count, offset);
+		return CBFS_MEDIA_INVALID_MAP_ADDRESS;
+	}
+	buffer->allocated += count;
+	buffer->last_allocate = count;
+	return address;
+}
+
+void *cbfs_simple_buffer_unmap(struct cbfs_simple_buffer *buffer,
+			       const void *address) {
+	// TODO Add simple buffer management so we can free more than last
+	// allocated one.
+	DEBUG("simple_buffer_unmap(address=0x%p): "
+	      "allocated=%d, size=%d, last_allocate=%d\n",
+	    address, buffer->allocated, buffer->size,
+	    buffer->last_allocate);
+	if ((buffer->buffer + buffer->allocated - buffer->last_allocate) ==
+	    address) {
+		buffer->allocated -= buffer->last_allocate;
+		buffer->last_allocate = 0;
+	}
+	return NULL;
 }

/**
@@ -158,4 +220,5 @@ int run_address(void *f)
    v = f;
    return v();
 }
+
 #endif
diff --git a/src/lib/cbfs_core.c b/src/lib/cbfs_core.c
index 15cb68e..6e4f489 100644
--- a/src/lib/cbfs_core.c
+++ b/src/lib/cbfs_core.c
@@ -1,7 +1,8 @@
 /*
- * This file is part of the libpayload project.
+ * This file is part of the coreboot project.
  *
  * Copyright (C) 2011 secunet Security Networks AG
+ * Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -27,14 +28,15 @@
  * SUCH DAMAGE.
  */

-/* The CBFS core requires a couple of #defines or functions to adapt it to the target environment:
+/* The CBFS core requires a couple of #defines or functions to adapt it to the
+ * target environment:
  *
  * CBFS_CORE_WITH_LZMA (must be #define)
  *      if defined, ulzma() must exist for decompression of data streams
  *
- * phys_to_virt(x), virt_to_phys(x)
- *      translate physical addresses to virtual and vice versa
- *      can be idempotent if no mapping is necessary.
+ * CBFS_HEADER_ROM_ADDRESS
+ *	ROM address (offset) of CBFS header. Underlying CBFS media may interpret
+ *	it in other way so we call this "address".
  *
  * ERROR(x...)
  *      print an error message x (in printf format)
@@ -45,105 +47,134 @@
  * DEBUG(x...)
  *      print a debug message x (in printf format)
  *
- * romstart()
- *      returns the start address of the ROM image, or 0xffffffff if ROM is
- *      top-aligned. This is a physical address.
- *
- * romend()
- *      returns the highest address of the ROM image + 1, for use if
- *      romstart() == 0xffffffff. This is a physical address.
  */

-#include <cbfs_core.h>
-
+#include <cbfs.h>
+#include <string.h>

-/* returns pointer to master header or 0xffffffff if not found */
-struct cbfs_header *get_cbfs_header(void)
+/* returns a pointer to CBFS master header, or CBFS_HEADER_INVALID_ADDRESS
+ *  on failure */
+const struct cbfs_header *cbfs_get_header(struct cbfs_media *media)
 {
-	struct cbfs_header *header;
-
-	/* find header */
-	if (romstart() == 0xffffffff) {
-		header = (struct cbfs_header*)phys_to_virt(*(uint32_t*)phys_to_virt(romend() + CBFS_HEADPTR_ADDR));
-	} else {
-		// FIXME: where's the master header on ARM (our current bottom-aligned platform)?
-		header = NULL;
+	const struct cbfs_header *header;
+	struct cbfs_media default_media;
+
+	if (media == CBFS_DEFAULT_MEDIA) {
+		media = &default_media;
+		if (init_default_cbfs_media(media) != 0) {
+			ERROR("Failed to initializee default media.\n");
+			return NULL;
+		}
+	}
+
+	media->open(media);
+	DEBUG("CBFS_HEADER_ROM_ADDRESS: 0x%x/0x%x\n", CBFS_HEADER_ROM_ADDRESS,
+	      CONFIG_ROM_SIZE);
+	header = media->map(media, CBFS_HEADER_ROM_ADDRESS, sizeof(*header));
+	media->close(media);
+
+	if (header == CBFS_MEDIA_INVALID_MAP_ADDRESS) {
+		ERROR("Failed to load CBFS header from 0x%x\n",
+		      CBFS_HEADER_ROM_ADDRESS);
+		return CBFS_HEADER_INVALID_ADDRESS;
    }
+
    if (CBFS_HEADER_MAGIC != ntohl(header->magic)) {
-		ERROR("Could not find valid CBFS master header at %p: %x vs %x.\n", header, CBFS_HEADER_MAGIC, ntohl(header->magic));
+		ERROR("Could not find valid CBFS master header at %x: "
+		      "%x vs %x.\n", CBFS_HEADER_ROM_ADDRESS, CBFS_HEADER_MAGIC,
+		      ntohl(header->magic));
    	if (header->magic == 0xffffffff) {
    		ERROR("Maybe ROM is not mapped properly?\n");
    	}
-		return (void*)0xffffffff;
+		return CBFS_HEADER_INVALID_ADDRESS;
    }
    return header;
 }

-// by must be power-of-two
-#define CBFS_ALIGN(val, by) (typeof(val))((uint32_t)(val + by - 1) & (uint32_t)~(by - 1))
-#define CBFS_ALIGN_UP(val, by) CBFS_ALIGN(val + 1, by)
-
 /* public API starts here*/
-struct cbfs_file *cbfs_find(const char *name)
+struct cbfs_file *cbfs_get_file(struct cbfs_media *media, const char *name)
 {
-	struct cbfs_header *header = get_cbfs_header();
-	if (header == (void*)0xffffffff) return NULL;
-
-	LOG("Looking for '%s'\n", name);
-
-	void *data, *dataend, *origdata;
-	/* find first entry */
-	if (romstart() == 0xffffffff) {
-		data = (void*)phys_to_virt(romend()) - ntohl(header->romsize) + ntohl(header->offset);
-		dataend = (void*)phys_to_virt(romend());
-	} else {
-		data = (void*)phys_to_virt(romstart()) + ntohl(header->offset);
-		dataend = (void*)phys_to_virt(romstart()) + ntohl(header->romsize);
-	}
-	dataend -= ntohl(header->bootblocksize);
-
-	int align = ntohl(header->align);
-
-	origdata = data;
-	while ((data < (dataend - 1)) && (data >= origdata)) {
-		struct cbfs_file *file = data;
-		if (memcmp(CBFS_FILE_MAGIC, file->magic, strlen(CBFS_FILE_MAGIC)) != 0) {
-			// no file header found. corruption?
-			// proceed in aligned steps to resynchronize
-			LOG("ERROR: No file header found at %p, attempting to recover by searching for header\n", data);
-			data = phys_to_virt(CBFS_ALIGN_UP(virt_to_phys(data), align));
-			continue;
-		}
-		DEBUG("Check '%s'\n", CBFS_NAME(file));
-		if (strcmp(CBFS_NAME(file), name) == 0) {
-			LOG("found.\n");
-			return file;
-		}
-		void *olddata = data;
-		data = phys_to_virt(CBFS_ALIGN(virt_to_phys(data) + ntohl(file->len) + ntohl(file->offset), align));
-		if (olddata > data) {
-			LOG("Something is wrong here. File chain moved from %p to %p\n", olddata, data);
+	const char *file_name;
+	uint32_t offset, align, romsize, name_len;
+	const struct cbfs_header *header;
+	struct cbfs_file file, *file_ptr;
+	struct cbfs_media default_media;
+
+	if (media == CBFS_DEFAULT_MEDIA) {
+		media = &default_media;
+		if (init_default_cbfs_media(media) != 0) {
+			ERROR("Failed to initializee default media.\n");
    		return NULL;
    	}
    }
-	return NULL;
-}
-
-void *cbfs_get_file(const char *name)
-{
-	struct cbfs_file *file = cbfs_find(name);

-	if (file == NULL) {
-		ERROR("Could not find file '%s'.\n", name);
+	if (CBFS_HEADER_INVALID_ADDRESS == (header = cbfs_get_header(media)))
    	return NULL;
-	}

-	return (void*)CBFS_SUBHEADER(file);
+	// Logical offset (for source media) of first file.
+	offset = ntohl(header->offset);
+	align = ntohl(header->align);
+	romsize = ntohl(header->romsize);
+
+	// TODO header->romsize seems broken now on ARM. Remove this when it's
+	// fixed.
+#if defined(CONFIG_ARCH_ARMV7) && CONFIG_ARCH_ARMV7
+	romsize = CONFIG_ROM_SIZE;
+#endif
+	DEBUG("offset: 0x%x, align: %d, romsize: %d\n", offset, align, romsize);
+
+	LOG("Looking for '%s' starting from 0x%x.\n", name, offset);
+	media->open(media);
+	while (offset < romsize &&
+	       media->read(media, &file, offset, sizeof(file)) == sizeof(file)) {
+		if (memcmp(CBFS_FILE_MAGIC, file.magic,
+			   sizeof(file.magic)) != 0) {
+			uint32_t new_align = align;
+			if (offset % align)
+				new_align += align - (offset % align);
+			ERROR("ERROR: No file header found at 0x%xx - "
+			      "try next aligned address: 0x%x.\n", offset,
+			      offset + new_align);
+			offset += new_align;
+			continue;
+		}
+		name_len = ntohl(file.offset) - sizeof(file);
+		DEBUG(" - load entry 0x%x file name (%d bytes)...\n", offset,
+		      name_len);
+
+		// load file name (arbitrary length).
+		file_name = (const char *)media->map(
+				media, offset + sizeof(file), name_len);
+		if (file_name == CBFS_MEDIA_INVALID_MAP_ADDRESS) {
+			ERROR("ERROR: Failed to get filename: 0x%x.\n", offset);
+		} else if (strcmp(file_name, name) == 0) {
+			int file_offset = ntohl(file.offset),
+			    file_len = ntohl(file.len);
+			LOG("Found file (offset=0x%x, len=%d).\n",
+			    offset + file_offset, file_len);
+			media->unmap(media, file_name);
+			file_ptr = media->map(media, offset,
+					      file_offset + file_len);
+			media->close(media);
+			return file_ptr;
+		} else {
+			LOG(" (unmatched file @0x%x: %s)\n", offset, file_name);
+			media->unmap(media, file_name);
+		}
+
+		// Move to next file.
+		offset += ntohl(file.len) + ntohl(file.offset);
+		if (offset % align)
+			offset += align - (offset % align);
+	}
+	media->close(media);
+	ERROR("ERROR: Not found.\n");
+	return NULL;
 }

-void *cbfs_find_file(const char *name, int type)
+void *cbfs_get_file_content(struct cbfs_media *media, const char *name, int type)
 {
-	struct cbfs_file *file = cbfs_find(name);
+	struct cbfs_file *file = cbfs_get_file(media, name);

if (file == NULL) {
    	ERROR("Could not find file '%s'.\n", name);
@@ -151,11 +182,12 @@ void *cbfs_find_file(const char *name, int type)
    }

if (ntohl(file->type) != type) {
-		ERROR("File '%s' is of type %x, but we requested %x.\n", name, ntohl(file->type), type);
+		ERROR("File '%s' is of type %x, but we requested %x.\n", name,
+		      ntohl(file->type), type);
    	return NULL;
    }

-	return (void*)CBFS_SUBHEADER(file);
+	return (void *)CBFS_SUBHEADER(file);
 }

int cbfs_decompress(int algo, void *src, void *dst, int len)
@@ -172,7 +204,9 @@ int cbfs_decompress(int algo, void *src, void *dst, int len)
    		return -1;
 #endif
    	default:
-			ERROR("tried to decompress %d bytes with algorithm #%x, but that algorithm id is unsupported.\n", len, algo);
+			ERROR("tried to decompress %d bytes with algorithm #%x,"
+			      "but that algorithm id is unsupported.\n", len,
+			      algo);
    		return -1;
    }
 }
diff --git a/src/lib/hardwaremain.c b/src/lib/hardwaremain.c
index eed243a..85c05f5 100644
--- a/src/lib/hardwaremain.c
+++ b/src/lib/hardwaremain.c
@@ -59,6 +59,7 @@ void hardwaremain(int boot_complete);
 void hardwaremain(int boot_complete)
 {
    struct lb_memory *lb_mem;
+	void *payload;

timestamp_stash(TS_START_RAMSTAGE);
    post_code(POST_ENTRY_RAMSTAGE);
@@ -141,8 +142,8 @@ void hardwaremain(int boot_complete)

timestamp_add_now(TS_LOAD_PAYLOAD);

-	void *payload;
-	payload = cbfs_load_payload(lb_mem, CONFIG_CBFS_PREFIX "/payload");
+	payload = cbfs_load_payload(CBFS_DEFAULT_MEDIA,
+				    CONFIG_CBFS_PREFIX "/payload");
    if (! payload)
    	die("Could not find a payload\n");

diff --git a/src/lib/selfboot.c b/src/lib/selfboot.c
index c5fb62a..56124da 100644
--- a/src/lib/selfboot.c
+++ b/src/lib/selfboot.c
@@ -536,12 +536,3 @@ out:
    return 0;
 }

-void *cbfs_load_payload(struct lb_memory *lb_mem, const char *name)
-{
-	struct cbfs_payload *payload;
-
-	payload = (struct cbfs_payload *)cbfs_find_file(name, CBFS_TYPE_PAYLOAD);
-
-	return payload;
-}
-
diff --git a/src/mainboard/google/snow/bootblock.c b/src/mainboard/google/snow/bootblock.c
index d5ee0a3..5b3efa0 100644
--- a/src/mainboard/google/snow/bootblock.c
+++ b/src/mainboard/google/snow/bootblock.c
@@ -39,9 +39,13 @@
 #include <drivers/maxim/max77686/max77686.h>

#include <console/console.h>
+#include <cbfs.h>

#define EXYNOS5_CLOCK_BASE		0x10010000

+/* TODO Move to Makefile.inc once we support adding bootblock stage files. */
+#include "cpu/samsung/exynos5-common/spi.c"
+
 /* FIXME(dhendrix): Can we move this SPI stuff elsewhere? */
 static void spi_rx_tx(struct exynos_spi *regs, int todo,
    		void *dinp, void const *doutp, int i)
diff --git a/src/mainboard/samsung/lumpy/romstage.c b/src/mainboard/samsung/lumpy/romstage.c
index 5600cf6..9bc193b 100644
--- a/src/mainboard/samsung/lumpy/romstage.c
+++ b/src/mainboard/samsung/lumpy/romstage.c
@@ -301,7 +301,7 @@ void main(unsigned long bist)
    	break;
    }

-	spd_file = cbfs_find("spd.bin");
+	spd_file = cbfs_get_file(CBFS_DEFAULT_MEDIA, "spd.bin");
    if (!spd_file)
    	die("SPD data not found.");
    if (spd_file->len < (spd_index + 1) * 256)
diff --git a/src/northbridge/amd/agesa/family15tn/fam15tn_callouts.c b/src/northbridge/amd/agesa/family15tn/fam15tn_callouts.c
index 7c3b0ac..8c5605c 100644
--- a/src/northbridge/amd/agesa/family15tn/fam15tn_callouts.c
+++ b/src/northbridge/amd/agesa/family15tn/fam15tn_callouts.c
@@ -398,7 +398,9 @@ AGESA_STATUS fam15tn_DefaultRet (UINT32 Func, UINT32 Data, VOID *ConfigPtr)
 AGESA_STATUS fam15tn_HookGfxGetVbiosImage(UINT32 Func, UINT32 FchData, VOID *ConfigPrt)
 {
    GFX_VBIOS_IMAGE_INFO  *pVbiosImageInfo = (GFX_VBIOS_IMAGE_INFO *)ConfigPrt;
-	pVbiosImageInfo->ImagePtr = cbfs_find_file("pci"CONFIG_VGA_BIOS_ID".rom", CBFS_TYPE_OPTIONROM);
+	pVbiosImageInfo->ImagePtr = cbfs_get_file_content(
+			CBFS_DEFAULT_MEDIA, "pci"CONFIG_VGA_BIOS_ID".rom",
+			CBFS_TYPE_OPTIONROM);
    /* printk(BIOS_DEBUG, "IMGptr=%x\n", pVbiosImageInfo->ImagePtr); */
    return pVbiosImageInfo->ImagePtr == NULL ? AGESA_WARNING : AGESA_SUCCESS;
 }
diff --git a/src/northbridge/intel/i82830/vga.c b/src/northbridge/intel/i82830/vga.c
index 1ec7f87..40e7d9d 100644
--- a/src/northbridge/intel/i82830/vga.c
+++ b/src/northbridge/intel/i82830/vga.c
@@ -32,7 +32,7 @@
 static void vga_init(device_t dev)
 {
    printk(BIOS_INFO, "Starting Graphics Initialization\n");
-	struct cbfs_file *file = cbfs_find("mbi.bin");
+	struct cbfs_file *file = cbfs_get_file(CBFS_DEFAULT_MEDIA, "mbi.bin");
    void *mbi = NULL;
    unsigned int mbi_len = 0;

diff --git a/src/northbridge/intel/sandybridge/raminit.c b/src/northbridge/intel/sandybridge/raminit.c
index b5a1c23..f25aaa1 100644
--- a/src/northbridge/intel/sandybridge/raminit.c
+++ b/src/northbridge/intel/sandybridge/raminit.c
@@ -252,7 +252,9 @@ void sdram_initialize(struct pei_data *pei_data)
    pei_data->tx_byte = console_tx_byte;

/* Locate and call UEFI System Agent binary. */
-	entry = (unsigned long)cbfs_find_file("mrc.bin", 0xab);
+	/* TODO make MRC blob (0xab?) defined in cbfs_core.h. */
+	entry = (unsigned long)cbfs_get_file_content(
+			CBFS_DEFAULT_MEDIA, "mrc.bin", 0xab);
    if (entry) {
    	int rv;
    	asm volatile (