No description
222381e390
Have the Skylake SOC generate ACPI timing values for the enabled I2C controllers instead of passing it in the DSDT with static timings. The timing values are generated from the controller clock speed and are more accurate than the hardcoded values that were in the ASL which were originally copied from Broadwell where the controller is running at a different clock speed... Additionally it is now possible for a board to override the values using devicetree.cb. If zero is passed in for SCL HCNT or LCNT then the kernel will generate its own timing using the same forumla, but if the SDA hold time value is zero the kernel will NOT generate a correct value and the SDA hold time may be incorrect. This was tested on the Chell platform to ensure all the I2C devices on the board are still operational with these new timing values. Change-Id: I4feb3df9e083592792f8fadd7105e081a984a906 Signed-off-by: Duncan Laurie <dlaurie@chromium.org> Reviewed-on: https://review.coreboot.org/15291 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org> |
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| 3rdparty | ||
| Documentation | ||
| payloads | ||
| src | ||
| util | ||
| .clang-format | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| COPYING | ||
| 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.