Files
system76-coreboot/payloads/libpayload
Julius Werner 8a1d11f797 libpayload: Expand setbits_le32() and fix readl() const-ness
setbits_le32() is not really arch-specific... the arch-specific part of
accessing memory is wrapped by readl() and writel(), and the endianness
can be accounted for with the right macros. Generalize the definitions,
add a be32 version and move them to endian.h so that all platforms can
use them. Also include endian.h from libpayload.h so we won't update any
payload's old use of the macros (endianness is something useful enough
to always have avalable anyway, and shouldn't clash with other things).
This also fixes a bug where these macros would only be available if
libpayload-config.h had been independently included before.

Also fix a bug with readl() macros on all archs where they refused to
work on const pointers (which they should).

CQ-DEPEND=CL:208712
BUG=None
TEST=Stuff still compiles. Built and booted on Storm.

Original-Change-Id: I01a7fbadbb5d740675657d95c1e969027562ba8c
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/208713
Original-Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Reviewed-by: David Hendricks <dhendrix@chromium.org>
(cherry picked from commit 951f8a6d77bc21bd793bf4f228a0965ade586f00)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I51c25f01b200b91abbe32c879905349bb05dc9c8
Reviewed-on: http://review.coreboot.org/8129
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins)
2015-01-12 05:56:01 +01:00
..
2015-01-12 05:55:30 +01:00
2015-01-12 05:55:30 +01:00
2015-01-09 07:06:51 +01:00
2012-04-04 00:40:31 +02:00
2015-01-12 05:55:30 +01:00

-------------------------------------------------------------------------------
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.