coreboot-kgpe-d16/payloads/libpayload
Julius Werner 25a282dabc arm: Thumb ALL the things!
This patch switches every last part of Coreboot on ARM over to Thumb
mode: libpayload, the internal libgcc, and assorted assembly files. In
combination with the respective depthcharge patch, this will switch to
Thumb mode right after the entry point of the bootblock and not switch
back to ARM until the final assembly stub that jumps to the kernel.

The required changes to make this work include some new headers and
Makefile flags to handle assembly files (using the unified syntax and
the same helper macros as Linux), modifying our custom-written libgcc
code for 64-bit division to support Thumb (removing some stale old files
that were never really used for clarity), and flipping the general
CFLAGS to Thumb (some more cleanup there as well while I'm at it).

BUG=None
TEST=Snow and Nyan still boot.

Original-Change-Id: I80c04281e3adbf74f9f477486a96b9fafeb455b3
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/182212
Original-Reviewed-by: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit 5f65c17cbfae165a95354146ae79e06c512c2c5a)

Conflicts:
	payloads/libpayload/include/arm/arch/asm.h
	src/arch/arm/Makefile.inc
	src/arch/arm/armv7/Makefile.inc

*** There is an issue with what to do with ramstage-S-ccopts, and
*** will need to be covered in additional ARM cleanup patches.

Change-Id: I80c04281e3adbf74f9f477486a96b9fafeb455b3
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Reviewed-on: http://review.coreboot.org/6930
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-11-09 01:37:13 +01:00
..
arch arm: Thumb ALL the things! 2014-11-09 01:37:13 +01:00
bin ARM: Generalize armv7 as arm. 2014-09-08 18:59:23 +02:00
configs ARM: Generalize armv7 as arm. 2014-09-08 18:59:23 +02:00
crypto libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2014-08-05 18:44:08 +02:00
curses libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2014-08-05 18:44:08 +02:00
drivers libpayload: usb: ehci: Honor 10ms reset recovery period 2014-10-29 19:20:59 +01:00
include arm: Thumb ALL the things! 2014-11-09 01:37:13 +01:00
libc libpayload: Add a timer_us() function. 2014-09-15 19:01:03 +02:00
libcbfs cbfs: Fix overwalk on file scan 2014-08-10 22:25:07 +02:00
liblzma LZMA: Add a version of ulzma which takes the input and output buffer sizes. 2014-08-10 22:29:51 +02:00
libpci libpayload: minor cleanups 2012-04-04 00:40:31 +02:00
sample libpayload: Fix missed CONFIG_ -> CONFIG_LP_ substitutions 2014-10-17 11:24:15 +02:00
tests libpayload: Change CONFIG_X86_SERIAL_CONSOLE to CONFIG_8250_SERIAL_CONSOLE 2014-08-28 01:40:48 +02:00
util libpayload: also support armv7-a toolchain 2014-10-16 15:54:16 +02:00
Config.in ARM: Generalize armv7 as arm. 2014-09-08 18:59:23 +02:00
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 libpayload: Don't use default path for kconfig 2014-10-17 11:25:10 +02:00
Makefile.inc libpayload: Build libpayload with debugging info turned up all the way. 2014-09-29 19:29:30 +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.