No description
dbadb1dd63
The current default memcpy first copies single bytes to align the amount, then copies the rest as full words. In practice, the start of a buffer is much more likely to be word-aligned then the end, and aligned word access are usually more efficient. This patch reorders those accesses to first copy as many full words as possible and then finish the rest with byte accesses to optimize this common case. This fixes a data abort when using USB on ARM without CONFIG_GPL. Due to some limitations of how DMA memory is set up in coreboot on ARM, it currently does not support unaligned accesses. (This could be fixed with a more complicated patch, but it's usually not an issue... unless, of course, your memcpy happens to be braindead). Also add word-aligned accesses to memset and memcmp while I'm at it, and make memcmp's return value standard's compliant. BUG=chrome-os-partner:24957 TEST=Manual Original-Change-Id: I2a7bcb35626a05a9a43fcfd99eb958b485d7622a Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/203547 Original-Reviewed-by: Stefan Reinauer <reinauer@chromium.org> Original-Reviewed-by: David Hendricks <dhendrix@chromium.org> (cherry picked from commit 05a64d2e107e1675cc3442e6dabe14a341e55673) Signed-off-by: Marc Jones <marc.jones@se-eng.com> Change-Id: I0030ca8a203c97587b0da31a0a5e9e11b0be050f Reviewed-on: http://review.coreboot.org/8126 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org> |
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| 3rdparty@a8b0c52850 | ||
| documentation | ||
| payloads | ||
| src | ||
| util | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| COPYING | ||
| 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 ------------------ * 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.