Files
system76-coreboot/payloads/libpayload
Julius Werner e00ba2168b libpayload: usb: Unify USB speed between XHCI stack and USB core
This patch removes the confusing concept of a special "xhci_speed" with
a different numeric value from the usual speed used throughout the USB
core (except for the places directly interacting with the xHC, which are
explicitly marked). It also moves the MPS0 decoding function into the
core and moves some definitions around in preparation of later changes
that will make the stack SuperSpeed-ready. It makes both set_address
implementations share a constant for the specification-defined
SetAddress() recovery delay and removes pointless additional delays from
the non-XHCI version.

Change-Id: I422379d05d4a502b12dae183504e5231add5466a
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/170664
Reviewed-by: Stefan Reinauer <reinauer@google.com>
Commit-Queue: Ronald Minnich <rminnich@chromium.org>
(cherry picked from commit f160d4439c0d7cea1d2e6b97207935d61dcbb2f2)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6776
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2014-09-04 01:28:42 +02:00
..
2014-08-10 22:25:07 +02:00
2012-04-04 00:40:31 +02:00
2014-08-09 17:30:33 +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.