No description
Find a file
Raul E Rangel 728c0787f2 mb/google/zork: Don't expose reset GPIO for touchscreen to OS
The Raydium ACPI entry currently provides a reset GPIO and an _ON/_OFF
method to the kernel. These are contradictory. The ownership of the GPIO
should be mutually exclusive between either the OS or the FW. Since we
have two methods exposed this causes the OS to reset the TS twice. Once
using the _ON method, and once using the GPIO. Additionally the _ON
method is waiting for 20ms after reset while the OS driver uses a 50ms
delay. The Raydium TS datasheet specifies 20ms for FW ready time, so the
OS driver is adding additional padding.

The reference design has a 32ms rise time on the reset line. So without
this patch, the OS tries to reset the TS using the _ON method and it
waits for 20ms. This is not enough time for the reset line to reach
high, let alone account for the FW ready time. The OS driver then tries
to reset the device by toggling the GPIO. It waits 50ms which is still
2ms less than required.

This CL removes the GPIO from being exported in the _CRS so the OS
driver won't try and reset the device. It also increases the reset delay
by 32ms to account for the rise time.

This isn't a complete fix. I think that the slow rise time is causing
some kind of metastability in the TS reset hardware. Using a script to
bind and unbind the TS driver, the TS device becomes unresponsive after
~200 iterations. The only way to reset the device is to power cycle.

The TS power is also not currently controlled by the power resource.
This means that we have no guarantee over when the reset line is
toggled. This will lead to issues while spending and resuming.

BUG=b:160854397
TEST=Boot trembyle and make sure TS works. Suspend/Resume trembyle 300+
times.

Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Change-Id: I23131be5d7109eed660a8bd6e2c156c015aa3c4e
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43467
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
2020-07-23 21:26:14 +00:00
3rdparty 3rdparty/libgfxinit: Update submodule pointer 2020-07-20 12:09:47 +00:00
configs configs/config.stm: Correct config file name 2020-07-21 22:08:04 +00:00
Documentation Doc/tutorial/part1.md: Show how to list toolchain targets 2020-07-22 04:56:25 +00:00
LICENSES drivers: Use SPDX identifiers 2020-05-25 22:19:21 +00:00
payloads libpayload: cbgfx: Add draw_line() 2020-07-23 05:09:31 +00:00
src mb/google/zork: Don't expose reset GPIO for touchscreen to OS 2020-07-23 21:26:14 +00:00
tests tests: Improve test_skip_atoi() in /lib/string-test test case 2020-07-12 19:38:39 +00:00
util inteltool/gpio: Add support for new Lewisburg chipsets 2020-07-21 16:40:48 +00:00
.checkpatch.conf
.clang-format lint/clang-format: set to 96 chars per line 2019-06-13 20:14:00 +00:00
.editorconfig Add .editorconfig file 2019-09-10 12:52:18 +00:00
.gitignore cbfstool: Build vboot library 2020-03-23 08:34:23 +00:00
.gitmodules Add qc_blobs repository 2020-06-30 08:57:03 +00:00
.gitreview
AUTHORS AUTHORS, util/: Drop individual copyright notices 2020-05-09 21:21:32 +00:00
COPYING
gnat.adc treewide: Remove "this file is part of" lines 2020-05-11 17:11:40 +00:00
MAINTAINERS MAINTAINERS: Add Jeremy Soller for ec/system76 and mb/system76 2020-07-23 09:30:48 +00:00
Makefile build system: Rely on xcompile for HOSTCC and HOSTCXX 2020-07-08 08:53:46 +00:00
Makefile.inc Add qc_blobs repository 2020-06-30 08:57:03 +00:00
README.md README.md: Remove link to deprecated wiki 2019-11-16 20:39:55 +00:00
toolchain.inc Remove MAYBE_STATIC_BSS and ENV_STAGE_HAS_BSS_SECTION 2020-05-26 15:04:08 +00:00

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_TOOLCHAIN Kconfig option if you're feeling lucky (no support in this case).
  • iasl (for targets with ACPI support)
  • pkg-config
  • libssl-dev (openssl)

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 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:

https://www.coreboot.org

You can contact us directly on the coreboot mailing list:

https://www.coreboot.org/Mailinglist

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.