c49782cbe7
Gru only uses USB 2.0 in firmware to avoid all the madness associated with Type-C port orientation and USB 3.0 tuning. We do this by isolating the SuperSpeed lines in the Type-C PHY so it looks like they aren't connected to the device. Unfortunately, some devices seem to already get "locked" into SuperSpeed mode as soon as they detect Rx terminations once, and can never snap out again on their own. Since the terminations are already connected during power-on reset we cannot disable them fast enough to prevent this, and the only solution we found to date is to power-cycle the whole USB port. Now, Gru's USB port power is controlled by the EC, and unfortunately we have no direct host command to control it. We do however have a command to force a certain USB PD "role", and forcing our host into "sink" mode makes it stop sourcing power to the port. So for lack of a saner solution we'll use this to work around our problem. BRANCH=gru BUG=chrome-os-partner:59346 TEST=Booted Kevin in recovery mode, confirmed that my "problem stick" gets detected immediately (whereas previously I had to unplug/replug it). Booted Kevin to OS in both developer and normal mode and confirmed that USB still seems to work. Change-Id: Ib3cceba9baa170b13f01bd5c01bd413be5b441ba Signed-off-by: Patrick Georgi <pgeorgi@chromium.org> Original-Commit-Id: cd695eda33299e50362f1096c46f2f5260c49036 Original-Change-Id: I2db3d6d3710d18a8b8030e94eb1ac2e931f22638 Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/413031 Reviewed-on: https://review.coreboot.org/17628 Tested-by: build bot (Jenkins) Reviewed-by: Martin Roth <martinroth@google.com>
------------------------------------------------------------------------------- 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.