53924240be
There is an optimization that can take place when hole carving in ranges above 4GiB. If the range is the last range then there is no need to carve UC holes out from the larger WB range. This optimization also has the same assumption of choosing WB as the default MTRR type: the OS needs to properly handle accessing realloacted MMIO resources with PAT so that the MTRR type can be overidden. Below are results using a combination of options. The board this was tested on has 10 variable MTRRs at its disposal. It has 4GiB of RAM. IO hole config #1: hole starts at 0xad800000 No CACHE_ROM and no WRCOMB resources (takes 4 MTRRs): MTRR: Physical address space: 0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6 0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0 0x00000000000c0000 - 0x00000000ad800000 size 0xad740000 type 6 0x00000000ad800000 - 0x0000000100000000 size 0x52800000 type 0 0x0000000100000000 - 0x000000014f600000 size 0x4f600000 type 6 MTRR: default type WB/UC MTRR counts: 4/6. MTRR: WB selected as default type. MTRR: 0 base 0x00000000ad800000 mask 0x0000007fff800000 type 0 MTRR: 1 base 0x00000000ae000000 mask 0x0000007ffe000000 type 0 MTRR: 2 base 0x00000000b0000000 mask 0x0000007ff0000000 type 0 MTRR: 3 base 0x00000000c0000000 mask 0x0000007fc0000000 type 0 No CACHE_ROM and 1 WRCOMB resource (takes 6 MTRRs): MTRR: Physical address space: 0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6 0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0 0x00000000000c0000 - 0x00000000ad800000 size 0xad740000 type 6 0x00000000ad800000 - 0x00000000d0000000 size 0x22800000 type 0 0x00000000d0000000 - 0x00000000e0000000 size 0x10000000 type 1 0x00000000e0000000 - 0x0000000100000000 size 0x20000000 type 0 0x0000000100000000 - 0x000000014f600000 size 0x4f600000 type 6 MTRR: default type WB/UC MTRR counts: 6/7. MTRR: WB selected as default type. MTRR: 0 base 0x00000000ad800000 mask 0x0000007fff800000 type 0 MTRR: 1 base 0x00000000ae000000 mask 0x0000007ffe000000 type 0 MTRR: 2 base 0x00000000b0000000 mask 0x0000007ff0000000 type 0 MTRR: 3 base 0x00000000c0000000 mask 0x0000007ff0000000 type 0 MTRR: 4 base 0x00000000d0000000 mask 0x0000007ff0000000 type 1 MTRR: 5 base 0x00000000e0000000 mask 0x0000007fe0000000 type 0 CACHE_ROM and no WRCOMB resources (takes 7 MTRRs): MTRR: Physical address space: 0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6 0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0 0x00000000000c0000 - 0x00000000ad800000 size 0xad740000 type 6 0x00000000ad800000 - 0x00000000ff800000 size 0x52000000 type 0 0x00000000ff800000 - 0x0000000100000000 size 0x00800000 type 5 0x0000000100000000 - 0x000000014f600000 size 0x4f600000 type 6 MTRR: default type WB/UC MTRR counts: 11/7. MTRR: UC selected as default type. MTRR: 0 base 0x0000000000000000 mask 0x0000007f80000000 type 6 MTRR: 1 base 0x0000000080000000 mask 0x0000007fe0000000 type 6 MTRR: 2 base 0x00000000a0000000 mask 0x0000007ff0000000 type 6 MTRR: 3 base 0x00000000ad800000 mask 0x0000007fff800000 type 0 MTRR: 4 base 0x00000000ae000000 mask 0x0000007ffe000000 type 0 MTRR: 5 base 0x00000000ff800000 mask 0x0000007fff800000 type 0 MTRR: 6 base 0x0000000100000000 mask 0x0000007f00000000 type 6 CACHE_ROM and 1 WRCOMB resource (takes 8 MTRRs): Previously this combination was impossible without the optimization. MTRR: Physical address space: 0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6 0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0 0x00000000000c0000 - 0x00000000ad800000 size 0xad740000 type 6 0x00000000ad800000 - 0x00000000d0000000 size 0x22800000 type 0 0x00000000d0000000 - 0x00000000e0000000 size 0x10000000 type 1 0x00000000e0000000 - 0x00000000ff800000 size 0x1f800000 type 0 0x00000000ff800000 - 0x0000000100000000 size 0x00800000 type 5 0x0000000100000000 - 0x000000014f600000 size 0x4f600000 type 6 MTRR: default type WB/UC MTRR counts: 12/8. MTRR: UC selected as default type. MTRR: 0 base 0x0000000000000000 mask 0x0000007f80000000 type 6 MTRR: 1 base 0x0000000080000000 mask 0x0000007fe0000000 type 6 MTRR: 2 base 0x00000000a0000000 mask 0x0000007ff0000000 type 6 MTRR: 3 base 0x00000000ad800000 mask 0x0000007fff800000 type 0 MTRR: 4 base 0x00000000ae000000 mask 0x0000007ffe000000 type 0 MTRR: 5 base 0x00000000d0000000 mask 0x0000007ff0000000 type 1 MTRR: 6 base 0x00000000ff800000 mask 0x0000007fff800000 type 0 MTRR: 7 base 0x0000000100000000 mask 0x0000007f00000000 type 6 IO hole config #1: hole starts at 0x80000000 No CACHE_ROM and no WRCOMB resources (takes 1 MTRRs): MTRR: Physical address space: 0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6 0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0 0x00000000000c0000 - 0x0000000080000000 size 0x7ff40000 type 6 0x0000000080000000 - 0x0000000100000000 size 0x80000000 type 0 0x0000000100000000 - 0x000000017ce00000 size 0x7ce00000 type 6 MTRR: default type WB/UC MTRR counts: 1/2. MTRR: WB selected as default type. MTRR: 0 base 0x0000000080000000 mask 0x0000007f80000000 type 0 No CACHE_ROM and 1 WRCOMB resource (takes 3 MTRRs): MTRR: Physical address space: 0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6 0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0 0x00000000000c0000 - 0x0000000080000000 size 0x7ff40000 type 6 0x0000000080000000 - 0x00000000d0000000 size 0x50000000 type 0 0x00000000d0000000 - 0x00000000e0000000 size 0x10000000 type 1 0x00000000e0000000 - 0x0000000100000000 size 0x20000000 type 0 0x0000000100000000 - 0x000000017ce00000 size 0x7ce00000 type 6 MTRR: default type WB/UC MTRR counts: 4/3. MTRR: UC selected as default type. MTRR: 0 base 0x0000000000000000 mask 0x0000007f80000000 type 6 MTRR: 1 base 0x00000000d0000000 mask 0x0000007ff0000000 type 1 MTRR: 2 base 0x0000000100000000 mask 0x0000007f00000000 type 6 CACHE_ROM and no WRCOMB resources (takes 3 MTRRs): MTRR: Physical address space: 0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6 0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0 0x00000000000c0000 - 0x0000000080000000 size 0x7ff40000 type 6 0x0000000080000000 - 0x00000000ff800000 size 0x7f800000 type 0 0x00000000ff800000 - 0x0000000100000000 size 0x00800000 type 5 0x0000000100000000 - 0x000000017ce00000 size 0x7ce00000 type 6 MTRR: default type WB/UC MTRR counts: 9/3. MTRR: UC selected as default type. MTRR: 0 base 0x0000000000000000 mask 0x0000007f80000000 type 6 MTRR: 1 base 0x00000000ff800000 mask 0x0000007fff800000 type 0 MTRR: 2 base 0x0000000100000000 mask 0x0000007f00000000 type 6 CACHE_ROM and 1 WRCOMB resource (takes 4 MTRRs): MTRR: Physical address space: 0x0000000000000000 - 0x00000000000a0000 size 0x000a0000 type 6 0x00000000000a0000 - 0x00000000000c0000 size 0x00020000 type 0 0x00000000000c0000 - 0x0000000080000000 size 0x7ff40000 type 6 0x0000000080000000 - 0x00000000d0000000 size 0x50000000 type 0 0x00000000d0000000 - 0x00000000e0000000 size 0x10000000 type 1 0x00000000e0000000 - 0x00000000ff800000 size 0x1f800000 type 0 0x00000000ff800000 - 0x0000000100000000 size 0x00800000 type 5 0x0000000100000000 - 0x000000017ce00000 size 0x7ce00000 type 6 MTRR: default type WB/UC MTRR counts: 10/4. MTRR: UC selected as default type. MTRR: 0 base 0x0000000000000000 mask 0x0000007f80000000 type 6 MTRR: 1 base 0x00000000d0000000 mask 0x0000007ff0000000 type 1 MTRR: 2 base 0x00000000ff800000 mask 0x0000007fff800000 type 0 MTRR: 3 base 0x0000000100000000 mask 0x0000007f00000000 type 6 Change-Id: Ia3195af686c3f0603b21f713cfb2d9075eb02806 Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/2959 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org> |
||
---|---|---|
3rdparty@ba8caa30bd | ||
documentation | ||
payloads | ||
src | ||
util | ||
.gitignore | ||
.gitmodules | ||
.gitreview | ||
COPYING | ||
Makefile | ||
Makefile.inc | ||
README |
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.