Julius Werner 4bfa29e947 arm64: xcompile: Add support for A53 erratum 843419
This patch adds support to enable a linker workaround to a hardware
erratum on some early Cortex-A53 revisions. Since the linker option was
added very recently, we use xcompile to test whether the toolchain
supports it first. It is also guarded by a Kconfig since only a few
ARM64 SoCs will need this and it incurs a performance penalty.

BRANCH=none
BUG=none
TEST=Turned it on or off for Smaug and confirmed that it (dis)appeared
in verbose make output accordingly.

Change-Id: I01c9642d3cf489134645f0db6f79f1c788ddb00d
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Original-Commit-Id: 57128785760c4dfa32d6e6d764756443a9323cb7
Original-Change-Id: Ia5dd124f484e38460d75fb864304e7e8b18d16b7
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/294745
Original-Reviewed-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-on: http://review.coreboot.org/11403
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
2015-08-28 06:46:09 +00:00
..
2015-05-21 20:50:25 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +02:00
2015-06-08 00:55:07 +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.