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coreboot for the Switch
d6aaca95f6
This is the intialization code specific to the Winbond
W972GG6JB-25 part using Synopsys DDR uMCTL and DDR Phy.
This is DDR2 initialization code only (currently present
on the bring up board). DDR3 initialization code will follow
for boards having DDR3 memory.
The programming procedure that is executed at power up to bring
up the uMCTL, PHY and memories into a state where reads and
writes to the memory can be performed is the following:
1. uPCTL (Universal DDR protocol controller) initialization
The timining registers TOGCNT1U, TINIT, TOGCNT100N and TRSTH
needed for driving the memory power-up sequence are programmed
as a function of the internal timers clock frequency.
Organization (memory chip specific) values are set
(column/bank/row address width and number of ranks), together
with other static values (latency, timing, power up configuration).
All these values are static, provided by the datasheet,
being determined by the memory type, size and frequency.
2. PHY initialization
The PHY is programmed with datasheet provided values,
specifying the initialization values for it to send to the
external memory (timing parameters).
Also, delay lines (DLL) and strength of drive pads are
calibrated (based on external conditions: temperature,
voltage, noise) and locked. After that, the PHY goes
through a trainig process (also dependent on the
current conditions at boot time) to establish precise
timing configuration between the DDR clock and DQS (data strobe)
and between DQS and DQ (data).
3. Memory power up
4. Switch from configuration state to access state.
BUG=chrome-os-partner:31438, chrome-os-partner:37087
TEST=tested on Pistachio bring up board -> DDR initialized
properly and ramstage executed correctly
DDR2 is also tested during chip sort.
Corner cases (performace of DDR in different conditions)
will be tested after the chip reaches a stable state.
BRANCH=none
Change-Id: I0093dc175d064aad03052d5281679b008c1bf012
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 3d0bacea0fd5bd3b12008b47e80de8398f447785
Original-Change-Id: I8437db6c84d77c4c51a3ee2b09cd3d14913c0d16
Original-Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/241424
Original-Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Commit-Queue: Vadim Bendebury <vbendeb@chromium.org>
Original-Tested-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: http://review.coreboot.org/9769
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <edward.ocallaghan@koparo.com>
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| 3rdparty@892a6976ba | ||
| documentation | ||
| payloads | ||
| src | ||
| util | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| COPYING | ||
| Makefile | ||
| Makefile.inc | ||
| README | ||
| toolchain.inc | ||
------------------------------------------------------------------------------- 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.