coreboot-kgpe-d16/payloads/libpayload
Raul E Rangel 9fc7b8e973 libpayload/x86/delay: Make arch_ndelay call apic_delay if delay is long
This reduces power consumption on grunt by over 3W when sitting at the
depthcharge recovery screen.

BUG=b:109749762
TEST=Booted grunt in the recovery screen and made sure it continued to
work.

Change-Id: Id079c099ee4cf6a07724241af4400063f4551668
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Reviewed-on: https://review.coreboot.org/28245
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Richard Spiegel <richard.spiegel@silverbackltd.com>
Reviewed-by: Julius Werner <jwerner@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
2018-09-12 14:15:48 +00:00
..
arch libpayload/x86/delay: Make arch_ndelay call apic_delay if delay is long 2018-09-12 14:15:48 +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/xhci: Replace raw values with constants 2018-08-08 21:57:22 +00:00
gdb libpayload/gdb: fix unused variable warning 2017-04-29 07:34:08 +02:00
include libpayload/libc/time: Add an arch_ndelay() 2018-09-12 14:15:18 +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 Rename __attribute__((packed)) --> __packed 2017-07-13 19:45:59 +00:00
liblzma
libpci libpayload: Add pci_free_dev() and some boilerplate 2017-12-07 21:51:24 +00:00
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 copy & update test routines from what-jenkins-does 2017-08-11 15:24:56 +00:00
README Use git HTTP URLs without `/p` in it 2018-04-17 10:38:06 +00:00

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 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.