d91f3a4eaf
The decompression is critical for speed of boot. So we sacrifice some
generated code size to optimize for speed.
This change speeds up the LZMA decompression between 3% and 6% at a
cost of just over 2k of additional code space.
BUG=b:223985641
TEST=Majolica
The test is done on Majolica and the result is listed below.
Time saved:
We tested the boot time with each flag for 10 times. The duration of
each decompression process is listed as below.
Load FSP-M Load ramstage Load payload
Ofast Os Ofast Os Ofast Os
------------------------------------------
62543 62959 20585 22458 9945 10626
62548 62967 20587 22461 9951 10637
62560 62980 20588 22478 9951 10641
62561 62988 20596 22478 9954 10643
62569 62993 20596 22479 9954 10643
62574 63000 20605 22492 9958 10647
62575 63026 20615 22495 9959 10647
62576 63038 20743 22614 9960 10647
62587 63044 20758 22625 9961 10647
62592 63045 20769 22637 9961 10647
-----------------------------------------
average 62568 63004 20644 22521 9955 10642
(unit: microseconds)
Size sacrificed:
The size of object file with -Os:
./build/ramstage/lib/lzmadecode.o: file format elf32-i386
4 .text.LzmaDecode 00000d84 00000000 00000000 00000076 2**0
CONTENTS, ALLOC, LOAD, READONLY, CODE
The size of object file with -Ofast:
./build/ramstage/lib/lzmadecode.o: file format elf32-i386
4 .text.LzmaDecode 00001719 00000000 00000000 00000080 2**4
CONTENTS, ALLOC, LOAD, READONLY, CODE
(Output by running "objdump -h ./build/ramstage/lib/lzmadecode.o")
We can see that size is increased from 3460 bytes to 5913 bytes, a
change of 2453 bytes or 171%.
Change-Id: Ie003164e2e93ba8ed3ccd207f3af31c6acf1c5e2
Signed-off-by: Zheng Bao <fishbaozi@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66392
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martin.roth@amd.corp-partner.google.com>
|
||
|---|---|---|
| 3rdparty | ||
| Documentation | ||
| LICENSES | ||
| configs | ||
| payloads | ||
| spd | ||
| src | ||
| tests | ||
| util | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .editorconfig | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| .mailmap | ||
| AUTHORS | ||
| COPYING | ||
| MAINTAINERS | ||
| Makefile | ||
| Makefile.inc | ||
| README.md | ||
| gnat.adc | ||
| toolchain.inc | ||
README.md
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:
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_TOOLCHAINKconfig option if you're feeling lucky (no support in this case). - iasl (for targets with ACPI support)
- pkg-config
- libssl-dev (openssl)
Optional:
- gdb (for better debugging facilities on some targets)
- ncurses (for
make menuconfigandmake 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:
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.