No description
5b1bb3d980
We found that Kevin board PHY0 and PHY1 eye-diagram margin is not enough to make compliance test pass, and the PHY0 USB SI is worse than PHY1, because of the higher PCB impedance. For PHY0, we can't improve the eye-diagram by SW PHY tuning, so we need to reduce the RBIAS resistance from 133 ohm to 115 ohm, it can help to increase the eye-height. For PHY1, we can improve the eye-diagram by setting the max pre-emphasis level. And after the above change, the USB2 signal amplitude will become larger at the test point near to SOC USB2 PHY, in order to avoid mis-trigger the disconnect detection (650mV), we need to disable pre-emphasize in eop state. BRANCH=None BUG=chrome-os-partner:53863 TEST=do USB 2.0 compliance test for Kevin C0 and C1 port. Change-Id: I95c0acd79623aeca9a0ae077b1dd3836d91fe561 Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: de3cdef128966d76e7d8e2ebd641763b911c3ad5 Original-Change-Id: I00cb325b9938e4276cc77b5d6f5faa7023379608 Original-Signed-off-by: William wu <wulf@rock-chips.com> Original-Reviewed-on: https://chromium-review.googlesource.com/390615 Original-Commit-Ready: Julius Werner <jwerner@chromium.org> Original-Tested-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/16911 Tested-by: build bot (Jenkins) Reviewed-by: Martin Roth <martinroth@google.com> |
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| Documentation | ||
| payloads | ||
| src | ||
| util | ||
| .checkpatch.conf | ||
| .clang-format | ||
| .gitignore | ||
| .gitmodules | ||
| .gitreview | ||
| COPYING | ||
| gnat.adc | ||
| MAINTAINERS | ||
| 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 ------------------ * 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) 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 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.