Patrick Georgi fdb348a1d1 libpayload: reintroduce optional PCI in XHCI driver
being a good citizen on the box, libpayload tries to return to EHCI
mode on shutdown, so a non-XHCI capable USB driver after it (eg. in
the OS) finds something to work with.

Change-Id: Id227d646e08a258b841c644263112f0815dd486c
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/4547
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-01-08 13:24:39 +01:00
..
2013-11-26 00:08:39 +01:00
2012-04-04 00:40:31 +02:00
2013-11-25 23:36:27 +01:00
2013-11-26 00:08:39 +01:00
2013-12-05 15:44:31 +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.