Files
system76-coreboot/payloads/libpayload
Paul Kocialkowski 7572e66bc7 libpayload: lpgcc: CFLAGS and CMDLINE order inversion
When building an external payload with lpgcc, the provided cmdline needs to be
included before libpayload-specific CFLAGS so that the include priority is the
payload first. This way, a payload using e.g. Kconfig that declares a config.h
will have its config.h included first, instead of libpayload's config.h.

Change-Id: I19b8012623e04c92a427d74904aed7f3bf5f0996
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Reviewed-on: http://review.coreboot.org/11113
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2015-08-09 13:07:04 +02:00
..
2015-05-21 20:50:25 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +02:00

-------------------------------------------------------------------------------
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 coreboot/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.