Julius Werner 58caa8ba8c libpayload: Reintroduce CONFIG_LP_CHROMEOS to set suitable defaults
Chrome OS builds always have some inherent differences to "standard"
libpayload configurations: they don't want to use curses or things like
storage drivers, they always use the coreboot framebuffer and USB, etc.
This patch reintroduces CONFIG_LP_CHROMEOS as an option that only
affects Kconfig defaults. This allows Chrome OS builds to select most of
what they need in one go and reduces board-specific .config files to
only the options that are really specific to that board.

Also restricts the 8250_SERIAL_CONSOLE Kconfig to only default to yes on
x86 boards, which probably makes sense for all of libpayload (some but
far from all ARM boards use 8250-compatible UARTs, and we should
probably not default a platform option unless it's going to be correct
with very high probability).

BRANCH=None
BUG=None
TEST=Built and booted Jerry and Oak.

Change-Id: Ie0c0593ffd399608d2cbfb83d20891f6f1864914
Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Commit-Id: e558f59
Original-Change-Id: I609637cd2ea7dfb4558aa3c04c90b64038c9ab57
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/347970
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/17024
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
2016-10-17 22:46:11 +02:00
..
2016-05-09 07:49:57 +02:00
2016-09-08 21:11:34 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +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.