No description
b4aaaa7632
Since we do not run option roms in normal mode nothing was initializing the BDA/EBDA and yet Linux depends very much on it having sane values here. For the most part the kernel tries to work around this not being initialized, but every once in awhile (1/300 boots or so) it would end up reading something that looked sane from BDA but was not and then it would panic. In this change the EBDA is unconditionally setup before devices are initialized. I'm not set on the location in dev_initialize() but there does not seem to be another place to hook it in so that it runs just once for ALL platforms regardless of whether they use option roms or not. (possibly hardwaremain?) The EBDA setup code has been moved into its own location in arch/x86/lib/ebda.c so it can be compiled in even if the option rom code is not. The low memory size is still set to 1MB which is enough to make linux happy without having to hook into each mainboard to get a more appropriate value. The setup_ebda() function takes inputs so it could be changed for a mainboard if needed. OLD/BROKEN would read garbage. Examples from different boots: ebda_addr=0x75e80 lowmem=0x1553400 ebda_addr=0x5e080 lowmem=0x3e51400 ebda_addr=0x7aa80 lowmem=0x2f8a800 NEW/FIXED now reads consistent values: ebda_addr=0xf6000 lowmem=0x100000 Change-Id: I6cb79f0e3e43cc65f7e5fe98b6cad1a557ccd949 Signed-off-by: Duncan Laurie <dlaurie@google.com> Reviewed-on: http://review.coreboot.org/769 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com> |
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| documentation | ||
| payloads | ||
| src | ||
| util | ||
| .gitignore | ||
| COPYING | ||
| Makefile | ||
| Makefile.inc | ||
| 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.