coreboot-kgpe-d16

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Christian Gmeiner 4412bc4ae8 OT200: reset MFGTP7 (backlight pwm) The CS5536 companion device has three different power domains. * working domain * standby domain * RTC domain When the system is "off" only the standby domain is powered. MFGPT[7:6] are member of the standby power domain. MFGPT7 is used to control the backlight of the device and so the timer gets used and configured during system boot. If the system does a reboot the timer stays configured and the Linux driver can not use it: "ot200-backlight: ot200-backlight.0: MFGPT 7 not availale" The cs5535-mfgpt has a function to hard-reset all MFGPTs but the system hangs after the first access to a MFGPT register - cause unknown. /* * This is a sledgehammer that resets all MFGPT timers. This is required by * some broken BIOSes which leave the system in an unstable state * (TinyBIOS 0.98, for example; fixed in 0.99). It's uncertain as to * whether or not this secret MSR can be used to release individual timers. * Jordan tells me that he and Mitch once played w/ it, but it's unclear * what the results of that were (and they experienced some instability). / static void reset_all_timers(void) { uint32_t val, dummy; / The following undocumented bit resets the MFGPT timers */ val = 0xFF; dummy = 0; wrmsr(MSR_MFGPT_SETUP, val, dummy); } After playing around with this undocumented MSR it looks like I only need to set bit 7 to free the MFGPT7. BTW, all MFGPT[0:5] will be reset during pll_reset(). Change-Id: I54a8d479ce495b0fc2f54db766a8d793bbb5d704 Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com> Reviewed-on: http://review.coreboot.org/2527 Tested-by: build bot (Jenkins) Reviewed-by: Jens Rottmann <JRottmann@LiPPERTembedded.de> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Marc Jones <marc.jones@se-eng.com>		2013-03-14 16:32:45 +01:00
3rdparty@dac1a18d18	Eagleheights DSDT: Grant OS control through OSC	2013-03-13 23:44:00 +01:00
documentation	sconfig: rename lapic_cluster -> cpu_cluster	2013-02-14 07:07:20 +01:00
payloads	libpayload: add support for vboot_handoff	2013-03-14 04:57:03 +01:00
src	OT200: reset MFGTP7 (backlight pwm)	2013-03-14 16:32:45 +01:00
util	GPLv2 notice: Unify all files to just use one space in »MA 02110-1301«	2013-03-01 10:16:08 +01:00
.gitignore	add a few entries to .gitignore	2013-01-10 22:51:20 +01:00
.gitmodules	Add 3rdparty as submodule	2012-05-01 00:08:37 +02:00
.gitreview	add .gitreview	2012-11-01 23:13:39 +01:00
COPYING	…
Makefile	build system: Retire REQUIRES_BLOB	2013-02-19 11:00:41 +01:00
Makefile.inc	x86: SMM Module Support	2013-03-14 05:01:50 +01:00
README	Update README with newer version of the text from the web page	2011-06-15 10:16:33 +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.