Go to file
Tobias Diedrich 0dab6d192b amd/sb800: Make UsbRxMode per-board customizable
On my Foxconn nT-A3500 on cold boot the board doesn't survive the soft
reboot in the UsbRxMode path and the vendor bios doesn't touch this
Cg2Pll voltage setting either.

The fixup code for UsbRxMode in src/vendorcode/amd/cimx/sb800/SBPort.c
doesn't seem to "CG PLL multiplier for USB Rx 1.1 mode", but rather
lowers the Cg2Pll voltage from the hw default of 1.222V to 1.1V
by setting Cg2Pll_IVR_TRIM in CGPllConfig5 to 1000.

See also USB_PLL_Voltage which is only used in the UsbRxMode code path.

However if this is already the efuse/eprom default for the SB800 then
UsbRxMode is a no-op, so whether or not it gets executed depends on the
very exact hw revision of the southbridge chip and could change between
two instances of the same board.

UsbRxMode used to be unitialized and was first set to default to 1
in http://review.coreboot.org/6474 (change I32237ff9,
southbridge/amd/cimx/sb800: Uninitialized variables in config func):

> > Why initialize those to 1? (just curious)
> See src/vendorcode/amd/cimx/sb800/SBTYPE.h
> git grep 'SbSpiSpeedSupport\|UsbRxMode'
> src/vendorcode/amd/cimx/sb800/SBTYPE.h

I could not find a corresponding errata in the SB800 errata list,
however errata 15 (USB Resets Asynchronously With Port CF9h Hard Reset)
might play into this being unsafe to do since the code uses CF9h to
reset.

So its possible that while previously undefined it still ended up
defaulting to 0 and the codepath exercised on my board is simply
buggy or there is a difference between a true "SB800" and the
"A50 Hudson M1" presumably used on my board.

Change-Id: I33f45925e222b86c0a97ece48f1ba97f6f878499
Signed-off-by: Tobias Diedrich <ranma+coreboot@tdiedrich.de>
Reviewed-on: http://review.coreboot.org/10549
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2015-10-24 00:21:01 +02:00
3rdparty cpu/amd/model_10xxx: Install AMD-provided microcode files in CBFS 2015-10-16 02:41:37 +00:00
Documentation documentation: Add documentation for timestamp library 2015-08-07 18:00:07 +02:00
payloads libpayload: Add ptrdiff_t typedef 2015-10-20 16:50:25 +02:00
src amd/sb800: Make UsbRxMode per-board customizable 2015-10-24 00:21:01 +02:00
util cbfstool: Make sure fileno is available on Cygwin 2015-10-23 20:44:35 +02:00
.gitignore .gitignore: adapt to new buildgcc version 2015-09-28 20:05:14 +00:00
.gitmodules submodules: add arm-trusted-firmware third-party repository 2015-06-23 08:20:24 +02:00
.gitreview
COPYING
MAINTAINERS MAINTAINERS: Fix format for file entries (F:) 2015-10-22 20:20:48 +02:00
Makefile Add cscope/ctags generation for the current project 2015-07-30 05:21:28 +02:00
Makefile.inc Makefile.inc: Put every tool in `TOOLLIST` on separate line 2015-10-18 16:39:08 +00:00
README README: improve description of compiler requirements 2015-07-30 05:11:33 +02:00
toolchain.inc linking: add and use LDFLAGS_common 2015-09-09 19:35:54 +00:00

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
------------------

 * make
 * gcc / g++
   Because Linux distribution compilers tend to use lots of patches. coreboot
   does lots of "unusual" things in its build system, some of which break due
   to those patches, sometimes by gcc aborting, sometimes - and that's worse -
   by generating broken object code.
   Two options: use our toolchain (eg. make crosstools-i386) or enable the
   ANY_TOOLCHAIN Kconfig option if you're feeling lucky (no support in this
   case).
 * iasl (for targets with ACPI support)

Optional:

 * doxygen (for generating/viewing documentation)
 * gdb (for better debugging facilities on some targets)
 * ncurses (for 'make menuconfig' and 'make nconfig')
 * 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.