coreboot/payloads/libpayload
Gabe Black 4dd549e18d libpayload: Add a timer_us() function.
This function returns the number of microseconds scaled from the number of raw
timer ticks. It accepts a base parameter which is subtracted from the current
time, which makes it easy to keep track of relative times.

BUG=None
TEST=With a corresponding change in depthcharge, built and booted on link.
BRANCH=None

Change-Id: I55f2f9e90c0e12cda430bbe88b044f12b0b563c8
Signed-off-by: Gabe Black <gabeblack@google.com>
Reviewed-on: https://chromium-review.googlesource.com/179600
Reviewed-by: Ronald Minnich <rminnich@chromium.org>
Commit-Queue: Gabe Black <gabeblack@chromium.org>
Tested-by: Gabe Black <gabeblack@chromium.org>
2013-12-17 04:26:45 +00:00
..
arch libpayload: Add vboot handoff parsing on ARM 2013-12-17 03:15:39 +00:00
bin ARM: Generalize armv7 as arm. 2013-10-02 09:18:44 +00:00
configs kirby is dead. long live the arm pit. 2013-11-07 23:42:47 +00:00
crypto libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2013-08-14 17:05:33 -07:00
curses libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2013-08-14 17:05:33 -07:00
drivers serial: Separate the serial hardware init and the serial console init. 2013-12-13 17:14:40 +00:00
include libpayload: Add a timer_us() function. 2013-12-17 04:26:45 +00:00
libc libpayload: Add a timer_us() function. 2013-12-17 04:26:45 +00:00
libcbfs cbfs: Fix overwalk on file scan 2013-08-19 17:29:35 -07:00
liblzma libpayload: Make lzma truncation non-fatal. 2013-08-19 19:04:35 -07:00
libpci libpayload: minor cleanups 2012-04-04 00:40:31 +02:00
sample fix compilation of hello.elf example payload. 2010-08-28 23:23:47 +00:00
tests libpayload: Change CONFIG_X86_SERIAL_CONSOLE to CONFIG_8250_SERIAL_CONSOLE 2013-09-27 14:05:53 +00:00
util Set check-lxdialog.sh mode properly 2013-10-22 21:41:24 +00:00
Config.in ARM: Generalize armv7 as arm. 2013-10-02 09:18:44 +00:00
Doxyfile Run doxygen -u on doxygen configuration files 2010-06-28 10:40:38 +00:00
LICENSES Since some people disapprove of white space cleanups mixed in regular commits 2010-04-27 06:56:47 +00:00
Makefile ARM: Generalize armv7 as arm. 2013-10-02 09:18:44 +00:00
Makefile.inc ARM: Generalize armv7 as arm. 2013-10-02 09:18:44 +00:00
README libpayload, superiotool: README: Prepend coreboot/ to path of change directory line 2013-04-04 17:22:15 +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.