No description
52669fc4dc
At higher SPI bus speeds the SPI RX value is not available in time for sampling at the normal time. Add a delay to ensure that we read the correct data. The value of 40ns is chosen arbitrarily. In my testing I can use a sample delay of 1 even at 24MHz. But since it is not necessary, I have left that case alone. It kicks in at 25MHz and up. BUG=chrome-os-partner:56556 BRANCH=none TEST=boot on gru and see no change at current speed Change-Id: I3ef335d9a532eaef1e76034bd02e185acf11176a Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: e9b620c47fc3e39211487507fadb8657afdebee7 Original-Change-Id: I65d66d752cbbbee4d02f475de23a52069a0e9782 Original-Signed-off-by: Simon Glass <sjg@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/381311 Original-Commit-Ready: Julius Werner <jwerner@chromium.org> Original-Tested-by: Simon Glass <sjg@google.com> Original-Reviewed-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/16707 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi <pgeorgi@google.com> |
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3rdparty | ||
Documentation | ||
payloads | ||
src | ||
util | ||
.checkpatch.conf | ||
.clang-format | ||
.gitignore | ||
.gitmodules | ||
.gitreview | ||
COPYING | ||
gnat.adc | ||
MAINTAINERS | ||
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 ------------------ * 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.