This patch adds I2C emulation in software through raw toggling of the
SDA/SCL lines. Platforms need to provide bindings to toggle their
respective I2C busses for this to work (e.g. by pinmuxing them as GPIOs,
currently only enabled for Tegra).
This is mostly useful as a debugging feature, to drive unusual states on
a bus and closely monitor the device output without the need of a bus
analyzer. It provides a few functions to "wedge" an I2C bus by aborting
a transaction at certain points, which can be used to test if a system
can correctly recover from an ill-timed reboot. However, it can also
dynamically replace the existing I2C transfer functions and drive
some/all I2C transfers on the system, which might be useful if a driver
for the actual I2C controller hardware is not (yet) available.
Based on original code by Doug Anderson <dianders@chromium.org> and
Hung-ying Tyan <tyanh@chromium.org> for the ChromeOS embedded
controller project.
BRANCH=None
BUG=chrome-os-partner:28323
TEST=Spread tegra_software_i2c_init()/tegra_software_i2c_disable()
through the code and see that everything still works.
Original-Change-Id: I9ee7ccbd1efb38206669a35d0c3318af16f8be63
Original-Signed-off-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/198791
Original-Reviewed-by: Doug Anderson <dianders@chromium.org>
Original-Reviewed-by: Tom Warren <twarren@nvidia.com>
Original-Reviewed-by: Stefan Reinauer <reinauer@chromium.org>
(cherry picked from commit 8f71503dbbd74c5298e90e2163b67d4efe3e89db)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Change-Id: Id6c5f75bb5baaabd62b6b1fc26c2c71d9f1ce682
Reviewed-on: http://review.coreboot.org/7947
Tested-by: build bot (Jenkins)
Reviewed-by: David Hendricks <dhendrix@chromium.org>
This is a fix for the 'Lost arb' we're seeing on Nyan* during
reboot stress testing. It occurs when we are slamming the
default PMIC registers with pmic_write_reg().
Currently, I've only captured this a few times, and the bus
clear seemed to work, as the PMIC writes continued (where
they'd hang the system before bus clear) for a couple of regs,
then it hangs hard, no messages, no 2nd lost arb, etc. So
I've added code to the PMIC write function that will reset the
SoC if any I2C error occurs. That seems to recover OK, i.e. on
the next reboot the PMIC writes all go thru, boot is OK, kernel
loads, etc.
BUG=chrome-os-partner:28323
BRANCH=nyan
TEST=Tested on nyan. Built for nyan and nyan_big.
Original-Change-Id: I1ac5e3023ae22c015105b7f0fb7849663b4aa982
Original-Signed-off-by: Tom Warren <twarren@nvidia.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/197732
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Original-Reviewed-by: Jimmy Zhang <jimmzhang@nvidia.com>
(cherry picked from commit f445127e2d9e223a5ef9117008a7ac7631a7980c)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Change-Id: I584d55b99d65f1e278961db6bdde1845cb01f3bc
Reviewed-on: http://review.coreboot.org/7897
Tested-by: build bot (Jenkins)
Reviewed-by: David Hendricks <dhendrix@chromium.org>
The new API is in use in depthcharge and is based around the "i2c_transfer"
function instead of i2c_read and i2c_write. The new function takes an array of
i2c_seg structures which represent each portion of the transfer after a start
bit and before the stop bit. If there's more than one segment, they're
seperated by repeated starts.
Some wrapper functions have also been added which make certain common
operations easy. These include reading or writing a byte from a register or
reading or writing a blob of raw data. The i2c device drivers generally use
these wrappers but can call the i2c_transfer function directly if the need
something different.
The tegra i2c driver was very similar to the one in depthcharge and was simple
to convert. The Exynos 5250 and 5420 drivers were ported from depthcharge and
replace the ones in coreboot. The Exynos 5420 driver was ported from the high
speed portion of the one in coreboot and was straightforward to port back. The
low speed portion and the Exynos 5250 drivers had been transplanted from U-Boot
and were replaced with the depthcharge implementation.
BUG=None
TEST=Built and booted on nyan with and without EFS. Built and booted on, pit
and daisy.
BRANCH=None
Original-Change-Id: I1e98c3fa2560be25444ab3d0394bb214b9d56e93
Original-Signed-off-by: Gabe Black <gabeblack@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/193561
Original-Reviewed-by: David Hendricks <dhendrix@chromium.org>
Original-Reviewed-by: Jimmy Zhang <jimmzhang@nvidia.com>
Original-Tested-by: Jimmy Zhang <jimmzhang@nvidia.com>
Original-Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Original-Commit-Queue: Gabe Black <gabeblack@chromium.org>
Original-Tested-by: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit 00c423fb2c06c69d580ee3ec0a3892ebf164a5fe)
This cherry-pick required additional changes to the following:
src/cpu/allwinner/a10/twi.c
src/drivers/xpowers/axp209/axp209.c
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Change-Id: I691959c66308eeeec219b1bec463b8b365a246d7
Reviewed-on: http://review.coreboot.org/7751
Tested-by: build bot (Jenkins)
Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com>
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
This is the only way to clear the error bits in the controller. Without
clearing them, every future transaction will look like it failed.
BUG=chrome-os-partner:27220
TEST=Built and booted on nyan with the TPM frequency turned up to 400 KHz.
BRANCH=None
Original-Change-Id: Ib654e60ec3039ad9f5f96aa7288d3d877e5c843a
Original-Signed-off-by: Gabe Black <gabeblack@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/191811
Original-Reviewed-by: Tom Warren <twarren@nvidia.com>
Original-Reviewed-by: Gabe Black <gabeblack@chromium.org>
Original-Commit-Queue: Gabe Black <gabeblack@chromium.org>
Original-Tested-by: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit 7b19a095652f1561590dcca922b9f8c308d7de9d)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Change-Id: I301b6694cc521601b618973de891e4ed44c6a97d
Reviewed-on: http://review.coreboot.org/7460
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Tested-by: build bot (Jenkins)
This uses the packet mode of the controller since that allows transfering more
data at a time.
Change-Id: I8329e5f915123cb55464fc28f7df9f9037b0446d
Signed-off-by: Gabe Black <gabeblack@google.com>
Reviewed-on: https://chromium-review.googlesource.com/172402
Reviewed-by: Ronald Minnich <rminnich@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Tested-by: Gabe Black <gabeblack@chromium.org>
Commit-Queue: Gabe Black <gabeblack@chromium.org>
(cherry picked from commit 4444cd626a55c8c2486cda6ac9cfece4e53dd0d3)
Signed-off-by: Isaac Christensen <isaac.christensen@se-eng.com>
Reviewed-on: http://review.coreboot.org/6703
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Julius Werner
Tom Warren
Gabe Black