coreboot/payloads/libpayload
Furquan Shaikh 7695bb7afe libpayload arm64: Initialize and enable MMU
What this change does:
1) Initialize limited page tables as soon as we jump into libpayload. Basically
two ranges are initialized. One is for the BASE_ADDRESS and other is for the
coreboot_tables. With page tables initialized and MMU enabled, we jump into
code to parse coreboot tables.
2) Once coreboot tables are parsed and we have complete picture of the memory,
we perform a complete page table initialzation and enable MMU and then jump to
payload.

Additionally, we also:
1) Initialize DMA memory on our own depending upon the memory map. It ensures
that the DMA buffer is placed in 32-bit memory.

CQ-DEPEND=CL:216826
BUG=chrome-os-partner:31634
BRANCH=None
TEST=Compiles successfully and we are able to start execution of libpayload in
EL2 and reach kernel login prompt

Change-Id: Ie0f47b7759d4ac65a6920f7f2f7502b889afda6d
Signed-off-by: Furquan Shaikh <furquan@google.com>
Reviewed-on: https://chromium-review.googlesource.com/216824
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: Furquan Shaikh <furquan@chromium.org>
Commit-Queue: Furquan Shaikh <furquan@chromium.org>
2014-09-17 01:23:49 +00:00
..
arch libpayload arm64: Initialize and enable MMU 2014-09-17 01:23:49 +00:00
bin libpayload: Add support for arm64 in libpayload 2014-06-07 01:28:57 +00:00
configs veyron: Rename "veyron" board to "veyron_pinky" 2014-09-12 00:56:07 +00:00
crypto libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2013-08-14 17:05:33 -07:00
curses libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2013-08-14 17:05:33 -07:00
drivers libpayload:support dwc2 usb driver 2014-09-04 15:47:17 +00:00
gdb libpayload: Let GDB stub read/write memory with aligned MMIO words 2014-07-22 01:24:00 +00:00
include libpayload arm64: Add support for mmu 2014-09-17 01:23:38 +00:00
libc libpayload console: Add check for already existing driver 2014-08-26 05:08:26 +00:00
libcbfs libpayload: Fix pointer related casts 2014-05-14 00:25:48 +00:00
liblzma libpayload: Make lzma truncation non-fatal. 2013-08-19 19:04:35 -07:00
libpci
sample
tests libpayload: Change CONFIG_X86_SERIAL_CONSOLE to CONFIG_8250_SERIAL_CONSOLE 2013-09-27 14:05:53 +00:00
util libpayload: Add support for arm64 in libpayload 2014-06-07 01:28:57 +00:00
Config.in libpayload:support dwc2 usb driver 2014-09-04 15:47:17 +00:00
Doxyfile
LICENSE_GPL libpayload: Introduce new Kconfig to explicitly allow GPL code 2014-06-13 20:37:29 +00:00
LICENSES libpayload: Introduce new Kconfig to explicitly allow GPL code 2014-06-13 20:37:29 +00:00
Makefile libpayload: Add support for arm64 in libpayload 2014-06-07 01:28:57 +00:00
Makefile.inc libpayload: Add remote GDB support 2014-06-11 03:33:56 +00:00
README libpayload, superiotool: README: Prepend coreboot/ to path of change directory line 2013-04-04 17:22:15 +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.