coreboot-kgpe-d16/payloads/libpayload
Gabe Black 001056f560 ARM: Tell the linker memset and memcpy are functions.
The memset and memcpy functions are assembled as ARM code, likely because
that's the default of the assembler. Without special annotation, the assembler
and linker don't know that those symbols are functions which need special
handling so that ARM/thumb issues are handled properly. This change adds that
annotation which gets those functions working in Coreboot which is compiled as
thumb. Libpayload and depthcharge are compiled as ARM so they don't *need* the
annotation since it just works out in ARM mode, but it's the safe thing to do
in case we change that in the future.

We should explicitly select ARM vs. thumb when assembling assembly files to be
consistent across builds and toolchains.

Change-Id: I814b137064cf46ae9e2744ff6c223b695dc1ef01
Signed-off-by: Gabe Black <gabeblack@chromium.org>
Reviewed-on: http://review.coreboot.org/3672
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2013-07-10 21:49:45 +02:00
..
arch ARM: Tell the linker memset and memcpy are functions. 2013-07-10 21:49:45 +02:00
bin libpayload: Make lpgcc wrapper usable for in-tree builds 2013-06-25 16:17:41 +02:00
configs libpayload: Update configs/defconfig file 2012-12-18 15:05:36 +01:00
crypto Change TARGET_I386 to ARCH_X86 2012-11-30 23:20:54 +01:00
curses libpayload: Use longer delay in tinycurses' wgetch() 2013-06-26 20:51:07 +02:00
drivers libpayload: ahci: Increase timeout for signature reading 2013-06-18 19:29:36 +02:00
include libpayload: Add strerror 2013-06-28 10:39:57 +02:00
libc libpayload: Add strerror 2013-06-28 10:39:57 +02:00
libcbfs cbfs_core.c: make cfbs searches even less verbose 2013-05-08 05:02:13 +02:00
liblzma libpayload: Don't do unaligned accesses during LZMA decompression 2013-03-13 23:42:09 +01:00
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: initial test case + tiny "framework" 2013-03-22 00:35:32 +01:00
util libpayload: Start using only internal and compiler headers. 2013-03-13 22:04:44 +01:00
Config.in libpayload: Fill gaps in the xHCI driver 2013-06-13 22:21:20 +02:00
Doxyfile
LICENSES
Makefile libpayload: Fix the config file dependency in the Makefile template 2013-03-18 20:46:09 +01:00
Makefile.inc libpayload: Don't sneak in compiler includes 2013-04-18 02:50:28 +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.