coreboot-kgpe-d16/payloads/libpayload
Julius Werner ca52a25882 libpayload: arm64: Conform to new coreboot lib_helpers.h and assume EL2
This patch adds the new, faster architectural register accessors to
libpayload that were already added to coreboot in CB:27881. It also
hardcodes the assumption that coreboot payloads run at EL2, which has
already been hardcoded in coreboot with CB:27880 (see rationale there).
This means we can drop all the read_current/write_current stuff which
added a lot of unnecessary helpers to check the current exception level.

This patch breaks payloads that used read_current/write_current
accessors, but it seems unlikely that many payloads deal with this stuff
anyway, and it should be a trivial fix (just replace them with the
respective _el2 versions).

Also add accessors for a couple of more registers that are required to
enable debug mode while I'm here.

Change-Id: Ic9dfa48411f3805747613f03611f8a134a51cc46
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/29017
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Patrick Rudolph <patrick.rudolph@9elements.com>
2018-10-12 20:14:54 +00:00
..
arch libpayload: arm64: Conform to new coreboot lib_helpers.h and assume EL2 2018-10-12 20:14:54 +00:00
bin
configs libpayload: cheza - fix config for chromium chroot build 2018-06-22 13:11:06 +00:00
crypto
curses payloads: Remove/fix trailing whitespace 2018-09-04 12:38:40 +00:00
drivers libpayload/drivers/usb: Fix leaks 2018-10-01 16:58:29 +00:00
gdb
include libpayload: arm64: Conform to new coreboot lib_helpers.h and assume EL2 2018-10-12 20:14:54 +00:00
libc libpayload/libc/time: Add an arch_ndelay() 2018-09-12 14:15:18 +00:00
libcbfs cbfs: Rename CBFS_TYPE_PAYLOAD to CBFS_TYPE_SELF 2018-05-04 10:30:24 +00:00
liblz4
liblzma
libpci
sample
tests
Doxyfile payloads: Remove/fix trailing whitespace 2018-09-04 12:38:40 +00:00
Kconfig libpayload: disable mouse on CHROMEOS 2018-05-18 16:00:18 +00:00
LICENSES
LICENSE_GPL
Makefile libpayload: Make libpayload compile using gnu11 2018-07-16 07:44:03 +00:00
Makefile.inc
README

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 https://www.coreboot.org for details on coreboot.


Installation
------------

 $ git clone https://review.coreboot.org/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 https://www.coreboot.org/Libpayload.

For additional information, patches, and discussions, please join the
coreboot mailing list at https://www.coreboot.org/Mailinglist, where most
libpayload developers are subscribed.


Copyright and License
---------------------

See LICENSES.