Many System on Chip(SoC) solutions are complex with multiple processors
on the same die dedicated to either general purpose of specialized
functions. Many examples do exist in today's SoCs from various vendors.
Typical examples are micro controllers such as an ARM M3/M0 doing a
offload of specific function such as event integration or power
management or controlling camera etc.
Traditionally, the responsibility of loading up such a processor with a
firmware and communication has been with a High Level Operating
System(HLOS) such as Linux. However, there exists classes of products
where Linux would need to expect services from such a processor or the
delay of Linux and operating system being able to load up such a
firmware is unacceptable.
To address these needs, we need some minimal capability to load such a
system and ensure it is started prior to an Operating System(Linux or
any other) is started up.
NOTE: This is NOT meant to be a solve-all solution, instead, it tries to
address certain class of SoCs and products that need such a solution.
A very simple model is introduced here as part of the initial support
that supports microcontrollers with internal memory (no MMU, no
execution from external memory, or specific image format needs). This
basic framework can then (hopefully) be extensible to other complex SoC
processor support as need be.
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Nishanth Menon <nm@ti.com>
Acked-by: Simon Glass <sjg@chromium.org>
This creates a new framework for handling of pin control devices,
i.e. devices that control different aspects of package pins.
This uclass handles pinmuxing and pin configuration; pinmuxing
controls switching among silicon blocks that share certain physical
pins, pin configuration handles electronic properties such as pin-
biasing, load capacitance etc.
This framework can support the same device tree bindings, but if you
do not need full interface support, you can disable some features to
reduce memory foot print. Typically around 1.5KB is necessary to
include full-featured uclass support on ARM board (CONFIG_PINCTRL +
CONFIG_PINCTRL_FULL + CONFIG_PINCTRL_GENERIC + CONFIG_PINCTRL_PINMUX),
for example.
We are often limited on code size for SPL. Besides, we still have
many boards that do not support device tree configuration. The full
pinctrl, which requires OF_CONTROL, does not make sense for those
boards. So, this framework also has a Do-It-Yourself (let's say
simple pinctrl) interface. With CONFIG_PINCTRL_FULL disabled, the
uclass itself provides no systematic mechanism for identifying the
peripheral device, applying pinctrl settings, etc. They must be
done in each low-level driver. In return, you can save much memory
footprint and it might be useful especially for SPL.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
Make "Generic Driver Options" menu show on the top in the Kconfig.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
Clocks are an important feature of platforms and have become increasing
complex with time. Most modern SoCs have multiple PLLs and dozens of clock
dividers which distribute clocks to on-chip peripherals.
Some SoC implementations have a clock API which is private to that SoC family,
e.g. Tegra and Exynos. This is useful but it would be better to have a
common API that can be understood and used throughout U-Boot.
Add a simple clock API as a starting point. It supports querying and setting
the rate of a clock. Each clock is a device. To reduce memory and processing
overhead the concept of peripheral clocks is provided. These do not need to
be explicit devices - it is possible to write a driver that can adjust the
I2C clock (for example) without an explicit I2C clock device. This can
dramatically reduce the number of devices (and associated overhead) in a
complex SoC.
Clocks are referenced by a number, and it is expected that SoCs will define
that numbering themselves via an enum.
Signed-off-by: Simon Glass <sjg@chromium.org>
Add support for a driver which sets up DRAM and can return information about
the amount of RAM available. This is a first step towards moving RAM init
to driver model.
Signed-off-by: Simon Glass <sjg@chromium.org>
Add a simple uclass for LEDs, so that these can be controlled by the device
tree and activated when needed. LEDs are referred to by their label.
This implementation requires a driver for each type of LED (e.g GPIO, I2C).
Signed-off-by: Simon Glass <sjg@chromium.org>
Some archs/boards specify their own default by pre-defining the config
which causes the Kconfig system to mix up the order of the configs in
the defconfigs... This will cause merge pain if allowed to proliferate.
Remove the configs that behave this way from the archs.
A few configs still remain, but that is because they only exist as
defaults and do not have a proper Kconfig entry. Those appear to be:
SPIFLASH
DISPLAY_BOARDINFO
Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
[trini: rastaban, am43xx_evm_usbhost_boot, am43xx_evm_ethboot updates,
drop DM_USB from MSI_Primo81 as USB_MUSB_SUNXI isn't converted yet to DM]
Signed-off-by: Tom Rini <trini@konsulko.com>
It is useful to be able to keep track of the available CPUs in a multi-CPU
system. This uclass is mostly intended for use with SMP systems.
The uclass provides methods for getting basic information about each CPU.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
On some SoCs, DMA-capable peripherals see a different address space to
the CPU's physical address space. Create an API to allow platform-agnostic
drivers to convert between the two address spaces when programming DMA
operations.
This API will exist on all platforms, but will have a dummy implementation
when this feature is not required. Other platforms will enable
CONFIG_PHYS_TO_BUS and provide the required implementation.
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Expand the help messages for each driver. Add missing Kconfig for I2C,
SPI flash and thermal.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
This would be useful to start moving various config options.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
