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>

1 files changed, 31 insertions, 6 deletions

diff --git a/src/include/cbfs.h b/src/include/cbfs.h
index b33e9327a8..9bfe2ceb96 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 <jordan@cosmicpenguin.net>
+ * 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