coreboot-kgpe-d16/payloads/libpayload
Nicolas Boichat 564720f2c8 libpayload: cbgfx: Allow rotation of the display
Sometimes the display native orientation does not match the device
default orientation, so allow rotation of the framebuffer before
it is displayed on screen.

set_pixel now take coordinates in the rotated coordinate system,
and converts the coordinates before writing to the framebuffer.

Also, screen.size now matches the rotated system (_not_ the
framebuffer size).

BUG=b:132049716
TEST=Boot krane, see that FW screen is orientation properly.

Change-Id: If9316c0ce33c17057372ef5995a2c68de4f11f02
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34732
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: Christian Walter <christian.walter@9elements.com>
2019-08-08 03:20:06 +00:00
..
arch
bin
configs payloads/libpayload: Update a Makefile for sample libpayload 2019-06-21 09:16:36 +00:00
crypto
curses libpayload: Enable -Wimplicit-fallthrough 2019-07-21 17:17:42 +00:00
drivers libpayload: cbgfx: Allow rotation of the display 2019-08-08 03:20:06 +00:00
gdb
include libpayload: cbgfx: Allow rotation of the display 2019-08-08 03:20:06 +00:00
libc vboot: deprecate vboot_handoff structure 2019-07-23 12:07:07 +00:00
libcbfs
liblz4
liblzma
libpci
sample payloads/libpayload: Update a Makefile for sample libpayload 2019-06-21 09:16:36 +00:00
tests
Doxyfile
Kconfig
LICENSES
LICENSE_GPL
Makefile
Makefile.inc libpayload: Enable -Wimplicit-fallthrough 2019-07-21 17:17:42 +00:00
README payloads/libpayload: Update a Makefile for sample libpayload 2019-06-21 09:16:36 +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

 $ make install (optional, will install into ./install per default)

On x86 systems, libpayload will always be 32-bit even if your host OS runs
in 64-bit, so you might have to install the 32-bit libgcc version.
On Debian systems you'd do 'apt-get install gcc-multilib' for example.

Run 'make distclean' before switching boards. This command will remove
your current .config file, so you need 'make menuconfig' again or
'make defconfig' in order to set up configuration. Default configuration
is based on 'configs/defconfig'. See the configs/ directory for examples
of configuration.


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.