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Ben Zhang 573429b09d samus: Set codec PDM clock output to 3MHz
Currently the rt5677 codec outputs 6MHz PDM clock which is
out-of-spec for the speaker amp SSM2537. The amp's GAIN_FS
pin is pulled down to PGND with a 47k resistor, so the
expected PDM clock is 64*FS (~3MHz) according to its datasheet.

The corresponding kernel patch that adds the PDM clock config
option is https://chromium-review.googlesource.com/#/c/230303/

BUG=chrome-os-partner:33303
BRANCH=samus
TEST=flash coreboot with this patch and see PDM CLK went
from 6MHz to 3MHz on samus with a scope.

Change-Id: Icf2c61930175bede1ee8ebc2b0fb17c2938b806c
Signed-off-by: Stefan Reinauer <reinauer@chromium.org>
Original-Commit-Id: b9ba4597515b2fbcc72fa22e296357c454175648
Original-Change-Id: I09acdf47bab4f641981491a84197de234918435e
Original-Signed-off-by: Ben Zhang <benzh@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/230344
Original-Reviewed-by: Dylan Reid <dgreid@chromium.org>
Original-Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/9277
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2015-04-04 12:40:26 +02:00
3rdparty@2bc495fd31 3rdparty: Update submodule to get Tegra 132 binaries 2015-03-07 17:50:58 +01:00
documentation documentation: begin documenting our use of git submodules 2015-02-13 09:33:24 +01:00
payloads libpayload: usb: xhci: set ENT flag in last Normal TRB 2015-03-23 18:41:18 +01:00
src samus: Set codec PDM clock output to 3MHz 2015-04-04 12:40:26 +02:00
util cbfstool: add filetypes for FSP, MRC, SPC and MRC_CACHE 2015-03-30 21:45:11 +02:00
.gitignore .gitignore: add the doxygen directory. 2014-12-14 23:30:45 +01:00
.gitmodules nvidia/cbootimage: avoid upstream's build system 2014-10-02 10:26:58 +02:00
.gitreview
COPYING
Makefile build system: Allow defining generic rules 2015-04-04 00:44:26 +02:00
Makefile.inc build system: Introduce manual file type 2015-04-04 00:44:52 +02:00
README
toolchain.inc mips: mips, not mipsel 2015-03-29 22:38:57 +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.