Hung-Te Lin d01d0368f4 libpayload: New CBFS to support multiple firmware media sources.
Upgrade CBFS in libpayload to use new media-based implementation from coreboot
( http://review.coreboot.org/#/c/2182/ ).

Old CBFS functions (cbfs_find, cbfs_find_file, get_cbfs_header) are still
supported, although the recommended way is to use new CBFS API.

To migrate your existing x86 payload source:
	- Change cbfs_find to cbfs_get_file
	- Change cbfs_find_file to cbfs_get_file_content
	- Prefix every CBFS call with a CBFS_DEFAULT_MEDIA argument.

Ex, char *jpeg_data = cbfs_find_file("splash.jpg", CBFS_TYPE_BOOTSPLASH);
 => char *jpeg_data = cbfs_get_file_content(
		CBFS_DEFAULT_MEDIA, "splash.jpg", CBFS_TYPE_BOOTSPLASH);

The legacy setup_cbfs_from_{ram,flash} is also supported, although the better
equivalent is to make a new media instance:
	struct cbfs_media ram_media;
	init_cbfs_ram_media(&ram_media, start, size);
	char *data = cbfs_get_file_content(&ram_media, "myfile", my_type);

Verified by being successfully linked with filo.

Change-Id: If797bc7e3ba975d7e3be905c59424f7a93b8ce11
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: http://review.coreboot.org/2191
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Anton Kochkov <anton.kochkov@gmail.com>
2013-02-12 11:34:20 +01:00
..
2012-12-14 22:29:48 +01:00
2012-11-30 23:20:54 +01:00
2012-12-14 22:29:48 +01:00
2011-08-04 08:11:21 +02:00
2012-04-04 00:40:31 +02:00
2013-02-01 20:15:47 +01:00
2012-12-14 22:29:48 +01:00
2012-12-14 22:29:48 +01:00

-------------------------------------------------------------------------------
libpayload README
-------------------------------------------------------------------------------

libpayload is a minimal library to support standalone payloads
that can be booted with firmware like coreboot. It handles the setup
code, and provides common C library symbols such as malloc() and printf().

Note: This is _not_ a standard library for use with an operating system,
rather it's only useful for coreboot payload development!
See http://coreboot.org for details on coreboot.


Installation
------------

 $ git clone http://review.coreboot.org/p/coreboot.git

 $ cd payloads/libpayload

 $ make menuconfig

 $ make

 $ sudo make install (optional, will install into /opt per default)

As libpayload is for 32bit x86 systems only, you might have to install the
32bit libgcc version, otherwise your payloads will fail to compile.
On Debian systems you'd do 'apt-get install gcc-multilib' for example.


Usage
-----

Here's an example of a very simple payload (hello.c) and how to build it:

 #include <libpayload.h>

 int main(void)
 {
     printf("Hello, world!\n");
     return 0;
 }

Building the payload using the 'lpgcc' compiler wrapper:

 $ lpgcc -o hello.elf hello.c

Please see the sample/ directory for details.


Website and Mailing List
------------------------

The main website is http://www.coreboot.org/Libpayload.

For additional information, patches, and discussions, please join the
coreboot mailing list at http://coreboot.org/Mailinglist, where most
libpayload developers are subscribed.


Copyright and License
---------------------

See LICENSES.