coreboot-kgpe-d16/payloads/libpayload
Julius Werner 68bdd00799 libpayload: Add div_round_up() function
The lack of a div_round_up() function in libpayload keeps being a
problem for payloads and has already caused us to sprinkle numerous
less-readable ALIGN_UP(n, d) / d throughout depthcharge. Let's add this
so we can avoid adding any more and then maybe cocchinelle them all over
later.

BRANCH=None
BUG=None
TEST=None

Change-Id: I241a52770a0edcf7003b48a81875b3fa0cb7ed53
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: a3f9514f9cfd325cc3c4b542020574b605fac935
Original-Change-Id: Ia55bd4bc52ab8a249b4854e40727cf6917af7b30
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/273050
Original-Reviewed-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-on: http://review.coreboot.org/10392
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2015-06-02 12:03:45 +02:00
..
arch arm64: Decouple MMU functions from memranges 2015-06-02 11:34:23 +02:00
bin libpayload: arch/mips: Add basic MIPS architecture support 2015-03-21 11:07:50 +01:00
configs cygnus: enable serial driver for depthcharge 2015-04-21 08:25:54 +02:00
crypto libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2014-08-05 18:44:08 +02:00
curses libpayload/PDcurses: avoid NULL deref 2015-01-03 23:58:22 +01:00
drivers Remove address from GPLv2 headers 2015-05-21 20:50:25 +02:00
gdb Remove address from GPLv2 headers 2015-05-21 20:50:25 +02:00
include libpayload: Add div_round_up() function 2015-06-02 12:03:45 +02:00
libc libpayload: cros: add serial number from coreboot table 2015-04-22 08:46:37 +02:00
libcbfs CBFS: Automate ROM image layout and remove hardcoded offsets 2015-04-14 09:01:27 +02:00
liblzma LZMA: Add a version of ulzma which takes the input and output buffer sizes. 2014-08-10 22:29:51 +02:00
libpci libpayload: minor cleanups 2012-04-04 00:40:31 +02:00
sample libpayload: Fix missed CONFIG_ -> CONFIG_LP_ substitutions 2014-10-17 11:24:15 +02:00
tests libpayload: Change CONFIG_X86_SERIAL_CONSOLE to CONFIG_8250_SERIAL_CONSOLE 2014-08-28 01:40:48 +02:00
util Remove address from GPLv2 headers 2015-05-21 20:50:25 +02:00
Config.in libpayload: add mediatek timer driver 2015-05-18 13:20:00 +02:00
Doxyfile Run doxygen -u on doxygen configuration files 2010-06-28 10:40:38 +00:00
LICENSES libpayload: Introduce new Kconfig to explicitly allow GPL code 2015-01-09 07:06:27 +01:00
LICENSE_GPL libpayload: Introduce new Kconfig to explicitly allow GPL code 2015-01-09 07:06:27 +01:00
Makefile libpayload: arch/mips: Add basic MIPS architecture support 2015-03-21 11:07:50 +01:00
Makefile.inc libpayload: avoid hanging on make junit.xml 2015-04-14 16:39:42 +02:00
README libpayload, superiotool: README: Prepend `coreboot/` to path of change directory line 2013-04-04 17:22:15 +02:00

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 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.