coreboot-kgpe-d16/payloads/libpayload
Nico Huber dc5c83812b libpayload/lpgcc: Turn references to build dir into a variable
Introduce a `$_OBJ` variable, that points to the build directory for
in-tree usage of `lpgcc`. If unset, the default `../build` relative
to the location of `lpgcc` is used.

Change-Id: I35112d7533d69aa51252dd2bceec010a62522403
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/47629
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2021-01-01 21:41:48 +00:00
..
arch libpayload: Provide API to expose MMU memery ranges for ARM64 2020-12-05 09:45:34 +00:00
bin libpayload/lpgcc: Turn references to build dir into a variable 2021-01-01 21:41:48 +00:00
configs Delete mainboard/google/cheza 2020-11-12 01:43:09 +00:00
crypto
curses
drivers libpayload/i8042: Add API to peek on keyboard input queue 2020-12-24 08:29:18 +00:00
gdb
include libpayload/i8042: Add API to peek on keyboard input queue 2020-12-24 08:29:18 +00:00
libc coreboot tables: Add SPI flash memory map windows to coreboot tables 2020-12-08 22:56:09 +00:00
libcbfs
liblz4
liblzma
libpci
sample libpayload: Move .xcompile into $(obj) 2021-01-01 21:30:44 +00:00
tests
.gitignore
Doxyfile
Kconfig libpayload/keyboard: Revise scancode set and translation config 2020-12-23 03:29:32 +00:00
LICENSES
LICENSE_GPL
Makefile libpayload: Move .xcompile into $(obj) 2021-01-01 21:30:44 +00:00
Makefile.inc libpayload: Keep a copy of .config in the build dir 2021-01-01 21:31:29 +00:00
README

README

-------------------------------------------------------------------------------
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.