While I2C supports multi-master buses this is difficult to get right.
The implementation on the master side in software is quite complex.
Clock-stretching and the arbitrary time that an I2C transaction can take
make it difficult to share the bus fairly in the face of high traffic.
When one or more masters can be reset independently part-way through a
transaction it is hard to know the state of the bus.
This driver provides a scheme based on two 'claim' GPIOs, one driven by the
AP (Application Processor, meaning the main CPU) and one driven by the EC
(Embedded Controller, a small CPU aimed at handling system tasks). With
these they can communicate and reliably share the bus. This scheme has
minimal overhead and involves very little code. It is used on snow to
permit the EC and the AP to share access to the main system PMIC and
battery. The scheme can survive reboots by either side without difficulty.
This scheme has been tested in the field with millions of devices.
Since U-Boot runs on the AP, the terminology used is 'our' claim GPIO,
meaning the AP's, and 'their' claim GPIO, meaning the EC's. This terminology
is used by the device tree bindings in Linux also.
Signed-off-by: Simon Glass <sjg@chromium.org>
Add a new I2C_MUX uclass. Devices in this class can multiplex between
several I2C buses, selecting them one at a time for use by the system.
The multiplexing mechanism is left to the driver to decide - it may be
controlled by GPIOs, for example.
The uclass supports only two methods: select() and deselect().
The current mux state is expected to be stored in the mux itself since
it is the only thing that knows how to make things work. The mux can
record the current state and then avoid switching unless it is necessary.
So select() can be skipped if the mux is already in the correct state.
Also deselect() can be made a nop if required.
Signed-off-by: Simon Glass <sjg@chromium.org>
Sometimes it is useful to be able to transfer a raw I2C message. This
happens when the chip address needs to be set manually, or when the data to
be sent/received is in another buffer.
Add a function to provide access to this.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
Move the flags and struct definitions higher in the file so that we can
reference them with functions declared in the driver model section.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
Add a way to dump the contents of an I2C message for debugging purposes.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
It is common for one node to reference another via a phandle. Add support
for obtaining an attached device by this method. As an example, a node may
have a 'power-supply' property which references a regulator, allowing the
driver to turn on its power.
Signed-off-by: Simon Glass <sjg@chromium.org>
The following commit enforces CONFIG_DM_ETH for USB Ethernet which
breaks any board using CONFIG_USB_HOST_ETHER without CONFIG_DM_ETH
which this patch fixes.
commit 69559093f6
dm: usb: Avoid using USB ethernet with CONFIG_DM_USB and no DM_ETH
Tested on Colibri T20/T30 as well as Apalis T30 with
CONFIG_USB_HOST_ETHER and CONFIG_USB_ETHER_ASIX enabled and a LevelOne
USB-0301 ASIX AX88772 dongle.
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Acked-by: Simon Glass <sjg@chromium.org>
Document the development flow on figuring out PIRQ information
during the U-Boot porting.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
The code in question polls an USB port status via USB_REQ_GET_STATUS
to determine whether there is a device on the port or not. The way to
figure that out is to check two bits. Those are wPortChange[0] and
wPortStatus[0].
The wPortChange[0] indicates whether some kind of a connection status
change happened on a port (a device was plugged or unplugged). The
wPortStatus[0] bit indicates the status of the connection (plugged or
unplugged).
The current code tests whether wPortChange[0] == wPortStatus[0] and
if that's the case, considers the loop polling for the presence of a
USB device on port finished.
This works for most USB sticks, since they come up really quickly and
trigger the USB port change detection before the first iteration of the
detection loop happens. Thus, both wPortChange[0] and wPortStatus[0]
are set to 1 and thus equal. The loop is existed in it's first iteration
and the stick is detected correctly.
The problem is with some obscure USB sticks, which take some time before
they pop up on the bus after the port was enabled. In this case, both
the wPortChange[0] and wPortStatus[0] are 0. They are equal again, so
the loop again exits in the first iteration, but this is incorrect, as
such USB stick didn't have the opportunity to get detected on the bus.
Rework the code such, that it checks for wPortChange[0] first to test
if any connection change happened at all. If no change occured, keep
polling. If a change did occur, test the wPortStatus[0] to see there is
some device present on the port and only if this is the case, break out
of the polling loop.
This patch also trims down the duration of the polling loop from 10s
per port to 1s per port. This is still annoyingly long, but there is
no better option in case of U-Boot unfortunatelly. This change will
most likely increase the duration of 'usb start' on some platforms,
but this is needed to fix a bug.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Hans de Goede <hdegoede@redhat.com>
This patch fixes operation of our on-board AX88772B chip without EEPROM
but with a ethaddr coming from the regular U-Boot environment. This is
a forward port of some remaining parts initially implemented by
Antmicro.
Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Acked-by: Marek Vasut <marex@denx.de>
usb_stor_reset is only defined when USB storage support is enabled, thus the
function is not declared when such support is missing.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
This adds some config options to the sunxi-common config to enable the USB
download gadget and the fastboot and USB mass storage functions.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Currently, the second use of a gadget will fail, while the first one works.
Forcing the EP0 at every enable fix this issue.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Now that some things were updated in Kconfig, they should be reflected on the
sunxi-common config too.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Now that the musb-new driver has a Kconfig, we can move Kconfig options to
enable controllers to it, so that it's easier in e.g. menuconfig.
In addition, this allows declaring support for USB_MUSB_HOST/GADGET in
defconfigs instead of the USB_MUSB_SUNXI controller, that will get selected
automatically when needed.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Having MUSB_HOST and MUSB_GADGET in Kconfig allows more flexibility with regard
to what Kconfig options to enable, such as USB_STORAGE or USB_KEYBOARD.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
USB-related options are usually prefixed with CONFIG_USB and platform-specific
adaptation for the MUSB controller already have a CONFIG_USB_MUSB prefix, so
this switches all MUSB-related options to a CONFIG_USB_MUSB prefix, for
consistency.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
There is no particular reason why the USB Kconfig option should be specific to
host mode. In prevision of adding MUSB host and gadget to Kconfig, this moves
the title and help message of the USB Kconfig option to a more generic format.
Adding comments to the usb Kconfig allows for a better separation and more
readability in generated configs and in menuconfig.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
The USB_ARCH_HAS_HCD currently serves no purpose and adds some confusion to the
required Kconfig options that are required to have USB support.
Dropping it makes things easier and doesn't break anything, since it was unused
anyways.
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
This patch makes the dwc2 controller like ehci / ohci / xhci controllers
by calling the board_usb_init() function from usb_lowlevel_init.
This can then be implemented by specific platforms to initialise
their USB hardware (phys / clocks etc).
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Add some documentation on the EFI implementation in U-Boot.
Signed-off-by: Ben Stoltz <stoltz@google.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
We cannot use this driver when running from EFI as we have no direct hardware
access. In fact coreboot uses a different driver which uses tables provided
by coreboot. So far it does not seem possible to use a normal video driver
when booting from EFI.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Disable a few things which interfere with the EFI init. This allows QEMU to
to boot into EFI, load a U-Boot payload then boot to the U-Boot prompt.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Disable a few things which interfere with the EFI init. This allows the
Minnowboard MAX to boot into EFI, load a U-Boot payload then boot to the
U-Boot prompt.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
When U-Boot is running from EFI some of the x86 init is replaced with
EFI-specific init. For example, since DRAM has already been set up, we only
need to find it, not init it. Add these functions so that boards can easily
allow booting from EFI if required.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
When U-Boot runs as an EFI payload it needs to avoid setting up the CPU
again. Also U-Boot currently does not handle interrupts for many devices, so
run with interrupts disabled.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
The EFI memory map is passed from the stub to U-Boot in a table. Add a
command to display it in a vaguely readable fashion.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested on QEMU
Tested-by: Bin Meng <bmeng.cn@gmail.com>
The EFI stub can pass a table to U-Boot with information about the memory map
Potentially other things will follow. Add a way to access this table.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
The EFI stub provides information to U-Boot in a table. This includes the
memory map which is needed to decide where to relocate U-Boot. Collect this
information in the early init code and store it in global_data.
Fix up the BIST code at the same time since we don't have it when booting
from EFI and can assume it is 0.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Most EFI implementations use 64-bit. Add a way to build U-Boot as a 64-bit
EFI payload. The payload unpacks a (32-bit) U-Boot and starts it. This can
be enabled for x86 boards at present.
Signed-off-by: Simon Glass <sjg@chromium.org>
Improvements to how the payload is built:
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
The procedure to drop from 64-bit mode to 32-bit is a bit messy. Add a
function to take care of it. It requires identity-mapped pages and that
the calling code is running below 4GB.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Rather than add these as open-coded values, create an enum with the commonly
used flags.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Add support for building a 32/64-bit EFI stub for x86. This involves
building the startup and relocation code for either i386 or x86_64.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
It is useful to be able to load U-Boot onto a board even if is it already
running EFI. This can allow access to the U-Boot command interface, flexible
booting options and easier development.
The easiest way to do this is to build U-Boot as a binary blob and have an
EFI stub copy it into RAM. Add support for this feature, targeting 32-bit
initially.
Also add a way to detect when U-Boot has been loaded via a stub. This goes
in common.h since it needs to be widely available so that we avoid redoing
initialisation that should be skipped.
Signed-off-by: Simon Glass <sjg@chromium.org>
Improvements to how the payload is built:
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Add a linker script and relocation code for building 64-bit EFI
applications. This can be used for the EFI stub.
Signed-off-by: Simon Glass <sjg@chromium.org>
Improvements to how the payload is built:
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Add configuration and Kconfig changes for this board.
Signed-off-by: Ben Stoltz <stoltz@google.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
This code currently requires CONFIG_SYS_TEXT_BASE but this should be
unnecessary. As a first step, remove the build-time limitation and report an
error instead.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
This contains just enough to bring up the serial UART.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Add support for the efi-x86 board, which supports running U-Boot as an
EFI 32-bit application.
Signed-off-by: Ben Stoltz <stoltz@google.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Add the required x86 glue code. This includes the initial start-up,
relocation and jumping to efi_main(). We also need to avoid fiddling with
interrupts.
Signed-off-by: Ben Stoltz <stoltz@google.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Bring in this file from Linux 4.1. It supports relocation features specific
to x86.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
When running as an EFI application we must skip relocation. Add support for
this in the x86 relocation code.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Add support for building U-Boot as an EFI application with a .efi suffix.
This can be loaded by EFI provided that EFI has the same bit width (32-
or 64-bit) as U-Boot. This unfortunate limitation is imposed by EFI.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Adjust the toolchain flags to build U-Boot as a relocatable shared library,
as required by EFI.
Signed-off-by: Ben Stoltz <stoltz@google.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
When U-Boot runs as an EFI application is does not have a definition of
CONFIG_SYS_TEXT_BASE. U-Boot is a relocatable application and the relocation
is done by EFI. U-Boot can be loaded at any address.
Ensure that this CONFIG option is not set in this case.
Signed-off-by: Ben Stoltz <stoltz@google.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Simon Glass
Marcel Ziswiler
Stephen Warren
Tom Rini
Bin Meng
Marek Vasut
Hans de Goede
Paul Kocialkowski
Maxime Ripard
Peter Griffin
Ben Stoltz