Files
system76-coreboot/payloads/libpayload
Julius Werner 3332c2dc6e tests: Disable -Wsource-mgr for clang
Unit tests fail on clang 13.0 with a cryptic

  error: _timestamp_size changed binding to STB_WEAK [-Werror,-Wsource-mgr]

Probably something related to the weird things we do to mock memlayout
areas. Too lazy to track it down. Let's just disable this
(clang-specific, not properly documented) warning flag.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: Ie49c9eef3c74592c068c899c6717621dbcb9f609
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59814
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jakub Czapiga <jacz@semihalf.com>
2021-12-07 17:47:09 +00:00
..
2021-10-11 12:59:57 +00:00
2020-03-02 15:03:03 +00:00
2021-10-11 12:59:57 +00:00
2021-10-11 12:59:57 +00:00

-------------------------------------------------------------------------------
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 https://www.coreboot.org for details on coreboot.


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

 $ git clone https://review.coreboot.org/coreboot.git

 $ cd coreboot/payloads/libpayload

 $ make menuconfig

 $ make

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

On x86 systems, libpayload will always be 32-bit even if your host OS runs
in 64-bit, so you might have to install the 32-bit libgcc version.
On Debian systems you'd do 'apt-get install gcc-multilib' for example.

Run 'make distclean' before switching boards. This command will remove
your current .config file, so you need 'make menuconfig' again or
'make defconfig' in order to set up configuration. Default configuration
is based on 'configs/defconfig'. See the configs/ directory for examples
of configuration.


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 https://www.coreboot.org/Libpayload.

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


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

See LICENSES.