coreboot/payloads/libpayload
Bartłomiej Grzesik 584f9bcc3f Add allocation of a buffer for pvmfw within cbmem
Add an allocation of an empty buffer for the Android protected virtual
machine firmware within cbmem. The buffer will be filled by the payload
and the purpose is to just reserve the memory. cbmem is used to make
sure that the region won't overlap with other reserved regions
or device regions.

BUG=b:354045389
BUG=b:359340876
TEST=depthcharge receives the buffer through lib_sysinfo
BRANCH=main

Change-Id: I48efc033ac0f5fbfcf3a52fabf40be016cd4c6f7
Signed-off-by: Bartłomiej Grzesik <bgrzesik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/87107
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jakub "Kuba" Czapiga <czapiga@google.com>
Reviewed-by: Julius Werner <jwerner@chromium.org>
2025-04-05 00:24:26 +00:00
..
arch
bin
configs
crypto
curses
drivers
gdb
include Add allocation of a buffer for pvmfw within cbmem 2025-04-05 00:24:26 +00:00
libc Add allocation of a buffer for pvmfw within cbmem 2025-04-05 00:24:26 +00:00
libcbfs
liblz4
liblzma
libpci
sample
tests
vboot
.gitignore
Doxyfile
Kconfig
LICENSE_GPL
LICENSES
Makefile
Makefile.mk
Makefile.payload
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.