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 <hungte@chromium.org>
Reviewed-on: http://review.coreboot.org/2182
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

2 files changed, 12 insertions, 4 deletions

diff --git a/src/arch/x86/boot/coreboot_table.c b/src/arch/x86/boot/coreboot_table.c
index 8dccd77287..04fba47b3f 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 72e70bacea..f65ced2746 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 |