coreboot/payloads/libpayload
Julius Werner 61c360a1c3 arm: Put exception_stack into BSS
"Hey guys, I have this awesome idea! How about we put a huge array
filled with 0xa5 into the data segment of our uncompressed romstage
for no particular reason? Give our SPI driver something to do so it
doesn't get too bored, you know?"

Guess it pays off to just hexdump our image and sanity-check it top to
bottom every once in a while...

Also reduces the size because 8K is crazy just to print a bunch of
registers (256 bytes ought to be enough for anybody).

BUG=None
TEST=Triggered an exception, still works as expected (and verified
romstage load size on Nyan is notably smaller now).

Change-Id: Icec0a711a1b5140d2ebcd98338ec638a4b6262fa
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/176762
Reviewed-by: Gabe Black <gabeblack@chromium.org>
Reviewed-by: Ronald Minnich <rminnich@chromium.org>
Reviewed-by: David Hendricks <dhendrix@chromium.org>
2013-11-20 06:51:02 +00:00
..
arch arm: Put exception_stack into BSS 2013-11-20 06:51:02 +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 libpayload: ehci: Fix byte count in dump_td() 2013-10-30 01:04:52 +00:00
include libpayload: adjust max number of memranges 2013-11-06 05:19:11 +00:00
libc libpayload: dma_malloc: Prevent warm reboot problems and add debugging 2013-09-17 03:22:09 +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.