Vadim Bendebury 11aaf1f42a ipq8064: Add work around for slow timer clock
Libpayload libc requires timer clock frequency to be at least 1MHz.
Ipq8064 code presently provides a single option of 32kHz. Pretend to
be running at 1 MHz without additional accuracy.

This is a hack which will be reverted as soon as the SOC is configured
to supply a faster running clock.

BUG=chrome-os-partner:27784, chrome-os-partner:28880
TEST=with other changes depthcharge boots to the CLI console

Original-Change-Id: I80ec6652bc5693a549668cd6e824e9cf5c26b182
Original-Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/201342
Original-Reviewed-by: David Hendricks <dhendrix@chromium.org>
(cherry picked from commit 466a59967b13986099106f8b44924648c1e6e6cd)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I113689191db70710e7a45ccd02d672f482343e35
Reviewed-on: http://review.coreboot.org/8004
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)
2015-01-04 00:27:50 +01:00
..
2014-12-30 19:12:11 +01:00
2012-04-04 00:40:31 +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.