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David Hendricks 42b1b8069c Exynos5420: ddr3: fine tuning the DDR3 timing values
Fine tuning DDR timings value for better stability

* Changed Data Driver Strength from 34 ohms to 30 ohms, expected to
  enhance signal integrity.
* Changed DQ signal from 0xf to 0x1f000f, to keep default value safe.
* Changed mrs[2] and added new mrs direct command for setting WL/RL
  without resetting DLL.
* Added explicit reset value write in phy_con0 instead of just setting
  a bit, to ensure that reset happens.
* Added DREX automatic control for ctrl_pd in none read memory state.

This is ported from: https://gerrit.chromium.org/gerrit/61405
Signed-off-by: David Hendricks <dhendrix@chromium.org>

Change-Id: I59e96e6dede7b49c6572548aca664d82ad110bb1
Reviewed-on: https://chromium-review.googlesource.com/66995
Reviewed-by: ron minnich <rminnich@chromium.org>
Commit-Queue: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
(cherry picked from commit ec34b711c6d270672c56d45c370ca14c0aa27ca3)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6611
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
2014-08-12 22:07:26 +02:00
3rdparty@45f0c04fd7 acpigen: Add acpigen_emit_eisaid. 2014-06-01 01:24:53 +02:00
documentation Documentation: Use correct file name for the build guide in the Makefile 2014-07-04 19:03:10 +02:00
payloads libpayload: ehci: Set explicit terminate bits in dummy_qh next pointers. 2014-08-12 22:06:55 +02:00
src Exynos5420: ddr3: fine tuning the DDR3 timing values 2014-08-12 22:07:26 +02:00
util util: replace fseek/ftell/rewind with fstat 2014-08-12 11:53:24 +02:00
.gitignore .gitignore: add 3 executables that can be built in util/ 2014-08-11 06:26:01 +02:00
.gitmodules gitmodules: Fix 3rdparty updates 2013-06-28 00:56:43 +02:00
.gitreview
COPYING
Makefile build system: avoid warning about missing .xcompile 2014-07-20 19:51:10 +02:00
Makefile.inc coreboot classes: Add dynamic classes to coreboot 2014-08-11 15:42:20 +02:00
README
toolchain.inc coreboot classes: Add dynamic classes to coreboot 2014-08-11 15:42:20 +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.