3cf94032bc
This is mostly written from scratch and uses common spd ddr2 decode functions. This improves the following: * This fixes incorrect CAS/Freq detection on DDR2; * Fixes tRFC computation; tRFC == 78 is a valid timing which is excluded and 0 ends up being used; (TESTED) * Timings selection does not use loops; * Removes ddr3 spd decode and is re-added in follow-up patches using common ddr3 spd functions; * Raminit would bail out if a dimm was unsupported, now in some cases it just marks the dimm slot as empty; * It dramatically reduces stack usage since it does not allocate 4 times 256 bytes to store full SPDs, amongs other unused things that were stored in sysinfo; * Reports when no dimms are present; * Uses i2c block read to read SPD which is about 5 times faster than bytewise read, with a fallback to smbus mode in case of failure, which does seem to happen when the system is forcefully powered off. Change-Id: I760eeaa3bd4f2bc25a517ddb1b9533c971454071 Signed-off-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-on: https://review.coreboot.org/19143 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Martin Roth <martinroth@google.com>
------------------------------------------------------------------------------- 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 https://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: * https://www.coreboot.org/Supported_Motherboards * https://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) * pkg-config * libssl-dev (openssl) 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 https://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 https://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: https://www.coreboot.org You can contact us directly on the coreboot mailing list: https://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.