Files
system76-coreboot/payloads/libpayload
Furquan Shaikh 5b1c328619 libpayload EHCI: Add memory barrier to EHCI driver
EHCI driver accesses mmio space using regular struct pointers. In order to avoid
any CPU re-ordering, memory barrier is required in async_set_schedule,
especially for arm64. Without the memory barrier, there seems to be re-ordering
taking place which leads to USB errors with some flash drives as well as
transfer errors in netboot.

BUG=chrome-os-partner:31533
BRANCH=None
TEST=With the memory barrier introduced, netboot for ryu completes transfer
without any error and finishes within 6-7 seconds.

Change-Id: Ib6d29dc79fd5722c27284478e8da316929e86bff
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 561bdd746c4d4446ce0a6d21337d354625d85ddc
Original-Change-Id: Ic05d47422312a1cddbebe3180f4f159853604440
Original-Signed-off-by: Furquan Shaikh <furquan@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/213917
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Tested-by: Furquan Shaikh <furquan@chromium.org>
Original-Commit-Queue: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/8732
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2015-03-19 23:24:23 +01:00
..
2015-01-12 05:55:30 +01:00
2012-04-04 00:40:31 +02:00
2015-01-12 05:55:30 +01:00

-------------------------------------------------------------------------------
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.