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Julius Werner 623368113c arm64: Decouple MMU functions from memranges
The current arm64 MMU interface is difficult to use in pre-RAM
environments. It is based on the memranges API which makes use of
malloc(), and early stages usually don't have a heap. It is also built
as a one-shot interface that requires all memory ranges to be laid out
beforehand, which is a problem when existing areas need to change (e.g.
after initializing DRAM).

The long-term goal of this patch is to completely switch to a
configure-as-you-go interface based on the mmu_config_range() function,
similar to what ARM32 does. As a first step this feature is added
side-by-side to the existing interface so that existing SoC
implementations continue to work and can be slowly ported over one by
one. Like the ARM32 version it does not garbage collect page tables that
become unused, so repeated mapping at different granularities will
exhaust the available table space (this is presumed to be a reasonable
limitation for a firmware environment and keeps the code much simpler).

Also do some cleanup, align comments between coreboot and libpayload for
easier diffing, and change all error cases to assert()s. Right now the
code just propagates error codes up the stack until it eventually
reaches a function that doesn't check them anymore. MMU configuration
errors (essentially just misaligned requests and running out of table
space) should always be compile-time programming errors, so failing hard
and fast seems like the best way to deal with them.

BRANCH=None
BUG=None
TEST=Compile-tested rush_ryu. Booted on Oak and hacked MMU init to use
mmu_config_range() insted of memranges. Confirmed that CRCs over all page
tables before and after the change are equal.

Change-Id: I93585b44a277c1d96d31ee9c3dd2522b5e10085b
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: f10fcba107aba1f3ea239471cb5a4f9239809539
Original-Change-Id: I6a2a11e3b94e6ae9e1553871f0cccd3b556b3e65
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/271991
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: http://review.coreboot.org/10304
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
2015-06-02 11:34:23 +02:00
3rdparty 3rdparty/blobs: Move submodule marker forward 2015-05-13 22:55:50 +02:00
Documentation Remove address from GPLv2 headers 2015-05-21 20:50:25 +02:00
payloads arm64: Decouple MMU functions from memranges 2015-06-02 11:34:23 +02:00
src arm64: Decouple MMU functions from memranges 2015-06-02 11:34:23 +02:00
util superiotool: detect the NCT5572D 2015-06-02 09:30:30 +02:00
.gitignore gitignore: Have multiple crossgcc versions 2015-05-25 21:26:02 +02:00
.gitmodules 3rdparty/vboot: Add vboot 2015-05-05 22:49:34 +02:00
.gitreview add .gitreview 2012-11-01 23:13:39 +01:00
COPYING update license template. 2006-08-12 22:03:36 +00:00
MAINTAINERS MAINTAINERS: grab build system responsibility 2015-05-22 22:47:03 +02:00
Makefile make: support absolute and relative obj= specifications 2015-05-08 19:47:11 +02:00
Makefile.inc build system: drop generic util/ %.c -> %.o rule 2015-05-25 18:05:06 +02:00
README Update README with newer version of the text from the web page 2011-06-15 10:16:33 +02:00
toolchain.inc build system: only query the compiler runtime's location once 2015-05-26 08:25:50 +02:00

README

-------------------------------------------------------------------------------
coreboot README
-------------------------------------------------------------------------------

coreboot is a Free Software project aimed at replacing the proprietary BIOS
(firmware) found in most computers.  coreboot performs a little bit of
hardware initialization and then executes additional boot logic, called a
payload.

With the separation of hardware initialization and later boot logic,
coreboot can scale from specialized applications that run directly
firmware, run operating systems in flash, load custom
bootloaders, or implement firmware standards, like PC BIOS services or
UEFI. This allows for systems to only include the features necessary
in the target application, reducing the amount of code and flash space
required.

coreboot was formerly known as LinuxBIOS.


Payloads
--------

After the basic initialization of the hardware has been performed, any
desired "payload" can be started by coreboot.

See http://www.coreboot.org/Payloads for a list of supported payloads.


Supported Hardware
------------------

coreboot supports a wide range of chipsets, devices, and mainboards.

For details please consult:

 * http://www.coreboot.org/Supported_Motherboards
 * http://www.coreboot.org/Supported_Chipsets_and_Devices


Build Requirements
------------------

 * gcc / g++
 * make

Optional:

 * doxygen (for generating/viewing documentation)
 * iasl (for targets with ACPI support)
 * gdb (for better debugging facilities on some targets)
 * ncurses (for 'make menuconfig')
 * flex and bison (for regenerating parsers)


Building coreboot
-----------------

Please consult http://www.coreboot.org/Build_HOWTO for details.


Testing coreboot Without Modifying Your Hardware
------------------------------------------------

If you want to test coreboot without any risks before you really decide
to use it on your hardware, you can use the QEMU system emulator to run
coreboot virtually in QEMU.

Please see http://www.coreboot.org/QEMU for details.


Website and Mailing List
------------------------

Further details on the project, a FAQ, many HOWTOs, news, development
guidelines and more can be found on the coreboot website:

  http://www.coreboot.org

You can contact us directly on the coreboot mailing list:

  http://www.coreboot.org/Mailinglist


Copyright and License
---------------------

The copyright on coreboot is owned by quite a large number of individual
developers and companies. Please check the individual source files for details.

coreboot is licensed under the terms of the GNU General Public License (GPL).
Some files are licensed under the "GPL (version 2, or any later version)",
and some files are licensed under the "GPL, version 2". For some parts, which
were derived from other projects, other (GPL-compatible) licenses may apply.
Please check the individual source files for details.

This makes the resulting coreboot images licensed under the GPL, version 2.