coreboot-kgpe-d16/payloads/libpayload
Julius Werner 1c6d919eb0 libpayload: usb: ehci: Honor 10ms reset recovery period
This patch adds the 10ms TRSTRCY delay between a reset and the following
Set Address command that is required by the USB 2.0 specification to the
EHCI root hub driver. The generic_hub driver that's used for XHCI and
external hubs already included this delay. This is such a glaring
violation of the spec that I'm really amazed how many USB 2.0 devices
we tested before seemed perfectly fine with responding to a Set Address
within 2 microframes of the reset...

It also increases the port reset hold delay by one millisecond to avoid
an ugly race condition on Tegra SoCs: they decided to time the 50ms
themselves instead of relying on the CPU to do it (fair enough), and to
automatically transition Port Reset to 0 and Port Enable to 1 after that
(bad idea). If the CPU's read-modify-write to clear Port Reset races
exactly with the host controller setting Port Enable, we may end up
clearing the bit again and going into the companion controller handoff
path later on. The added millisecond shouldn't cause any problems for
other host controllers and is not a big deal compared to other delays in
this code path.

BUG=chrome-os-partner:26749
TEST=Run several dozen reboot loops with The USB Stick of Death (TM) (a
blue Patriot XT 13fe:5200 with bcdDevice = 1.00), make sure it always
gets detected correctly.

Original-Change-Id: Idd3329ae6d7e5e1c07a84a5475549b3459836b31
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/189872
Original-Reviewed-by: Gabe Black <gabeblack@chromium.org>
Original-Reviewed-by: Jim Lin <jilin@nvidia.com>
Original-Reviewed-by: Hung-Te Lin <hungte@chromium.org>
(cherry picked from commit 4deca38e9d79f6373f4418fcaf51a6945232c8b8)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I68a29bfd2e0f30409fbfc330b2575f0f9f61a79d
Reviewed-on: http://review.coreboot.org/7221
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2014-10-29 19:20:59 +01:00
..
arch arm: Fix up new cache flush algorithm and replace dcache_*_all() with it 2014-09-29 17:26:45 +02:00
bin ARM: Generalize armv7 as arm. 2014-09-08 18:59:23 +02:00
configs ARM: Generalize armv7 as arm. 2014-09-08 18:59:23 +02:00
crypto libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2014-08-05 18:44:08 +02:00
curses libpayload: Change CONFIG_* to CONFIG_LP_* in the kconfig. 2014-08-05 18:44:08 +02:00
drivers libpayload: usb: ehci: Honor 10ms reset recovery period 2014-10-29 19:20:59 +01:00
include libpayload: Add missing cache API stub to x86 2014-09-25 18:33:07 +02:00
libc libpayload: Add a timer_us() function. 2014-09-15 19:01:03 +02:00
libcbfs cbfs: Fix overwalk on file scan 2014-08-10 22:25:07 +02:00
liblzma LZMA: Add a version of ulzma which takes the input and output buffer sizes. 2014-08-10 22:29:51 +02:00
libpci libpayload: minor cleanups 2012-04-04 00:40:31 +02:00
sample libpayload: Fix missed CONFIG_ -> CONFIG_LP_ substitutions 2014-10-17 11:24:15 +02:00
tests libpayload: Change CONFIG_X86_SERIAL_CONSOLE to CONFIG_8250_SERIAL_CONSOLE 2014-08-28 01:40:48 +02:00
util libpayload: also support armv7-a toolchain 2014-10-16 15:54:16 +02:00
Config.in ARM: Generalize armv7 as arm. 2014-09-08 18:59:23 +02:00
Doxyfile Run doxygen -u on doxygen configuration files 2010-06-28 10:40:38 +00:00
LICENSES Since some people disapprove of white space cleanups mixed in regular commits 2010-04-27 06:56:47 +00:00
Makefile libpayload: Don't use default path for kconfig 2014-10-17 11:25:10 +02:00
Makefile.inc libpayload: Build libpayload with debugging info turned up all the way. 2014-09-29 19:29:30 +02:00
README libpayload, superiotool: README: Prepend `coreboot/` to path of change directory line 2013-04-04 17:22:15 +02:00

README

-------------------------------------------------------------------------------
libpayload README
-------------------------------------------------------------------------------

libpayload is a minimal library to support standalone payloads
that can be booted with firmware like coreboot. It handles the setup
code, and provides common C library symbols such as malloc() and printf().

Note: This is _not_ a standard library for use with an operating system,
rather it's only useful for coreboot payload development!
See http://coreboot.org for details on coreboot.


Installation
------------

 $ git clone http://review.coreboot.org/p/coreboot.git

 $ cd coreboot/payloads/libpayload

 $ make menuconfig

 $ make

 $ sudo make install (optional, will install into /opt per default)

As libpayload is for 32bit x86 systems only, you might have to install the
32bit libgcc version, otherwise your payloads will fail to compile.
On Debian systems you'd do 'apt-get install gcc-multilib' for example.


Usage
-----

Here's an example of a very simple payload (hello.c) and how to build it:

 #include <libpayload.h>

 int main(void)
 {
     printf("Hello, world!\n");
     return 0;
 }

Building the payload using the 'lpgcc' compiler wrapper:

 $ lpgcc -o hello.elf hello.c

Please see the sample/ directory for details.


Website and Mailing List
------------------------

The main website is http://www.coreboot.org/Libpayload.

For additional information, patches, and discussions, please join the
coreboot mailing list at http://coreboot.org/Mailinglist, where most
libpayload developers are subscribed.


Copyright and License
---------------------

See LICENSES.