There is sort-of race condition when a pinctrl device is probed. The pinctrl
function is called which may end up using the same device as is being
probed. This results in operations being used before the device is actually
probed.
For now, disallow pinctrl operations on pinctrl devices while probing. An
alternative solution would be to move the operation to later in the
device_probe() function (for pinctrl devices only) but this needs more
thought.
Signed-off-by: Simon Glass <sjg@chromium.org>
At present the uclass's post_bind() method is called before the driver's
bind() method. This means that the uclass cannot use any of the information
set up by the driver. Move it later in the sequence to permit this.
This is an ordering change which is always fairly major in nature. The main
impact is that devices which have children will not see them appear in their
bind() method. From what I can see, existing drivers do not look at their
children in the bind() method, so this should be safe.
Conceptually this change seems to result in a 'more correct' ordering, since
the uclass (which is broader than the device) gets the last word.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
Add new api to get device address based on index.
Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Acked-by: Jagan Teki <jteki@openedev.com>
[Rebased on master]
Signed-off-by: Jagan Teki <jteki@openedev.com>
The Device Model sequence alias feature is required by some Uclasses.
Instead of disabling the feature for all SPL targets allow it to be
configured.
The config option is disabled by default to reduce code size for targets
that are not interested or do not require this feature.
Signed-off-by: Nathan Rossi <nathan@nathanrossi.com>
Acked-by: Simon Glass <sjg@chromium.org>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Marek Vasut <marex@denx.de>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Stefan Roese <sr@denx.de>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Some platforms need to ability to configure an offset to the standard
addresses extracted from the device-tree. This patch allows this by
adding a function to DM to configure this offset (if needed).
Signed-off-by: Stefan Roese <sr@denx.de>
Acked-by: Simon Glass <sjg@chromium.org>
Cc: Simon Glass <sjg@chromium.org>
Fixed space before tab:
Signed-off-by: Simon Glass <sjg@chromium.org>
The current name is inconsistent with other driver model data access
functions. Rename it and fix up all users.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
The current "simple" address translation simple_bus_translate() is not
working on some platforms (e.g. MVEBU). As here more complex "ranges"
properties are used in many nodes (multiple tuples etc). This patch
enables the optional use of the common fdt_translate_address() function
which handles this translation correctly.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Currently when driver model starts up it finds the root uclass and the
pinctrl uclass. This is because even the root node handles pinctrl
processing.
But this is not useful. The root node is not a real hardware device so
cannot require any particular pinmux settings. Also it means that the
memory leak tests fails, since they end up freeing more memory than
they allocate: the marker it set after the root device and pinctrl
uclass are allocated, and later once the pinctrl uclass is freed the memory
used by driver model is less than when the marker was set.
If a platform needs 'core' pin mulitplex settings it can do this with
a driver that is probed on start-up. It would be an abuse of the root node
to use this for pinctrl.
To avoid this problem, only process pinctrl settings for non-root nodes.
Signed-off-by: Simon Glass <sjg@chromium.org>
fdtdec_get_addr_size() hard-codes the number of cells used to represent
an address or size in DT. This is incorrect in many cases depending on
the DT binding for a particular node or property (e.g. it is incorrect
for the "reg" property). In most cases, DT parsing code must use the
properties #address-cells and #size-cells to parse addres properties.
This change splits up the implementation of fdtdec_get_addr_size() so
that the core logic can be used for both hard-coded and non-hard-coded
cases. Various wrapper functions are implemented that support cases
where hard-coded cell counts should or should not be used, and where
the client does and doesn't know the parent node ID that contains the
properties #address-cells and #size-cells.
dev_get_addr() is updated to use the new functions.
Core functionality in fdtdec_get_addr_size_fixed() is widely tested via
fdtdec_get_addr_size(). I tested fdtdec_get_addr_size_auto_noparent() and
dev_get_addr() by manually modifying the Tegra I2C driver to invoke them.
Much of the core implementation of fdtdec_get_addr_size_fixed(),
fdtdec_get_addr_size_auto_parent(), and
fdtdec_get_addr_size_auto_noparent() comes from Thierry Reding's
previous commit "fdt: Fix fdtdec_get_addr_size() for 64-bit".
Based-on-work-by: Thierry Reding <treding@nvidia.com>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Michal Suchanek <hramrach@gmail.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
Dropped #define DEBUG at the top of fdtdec.c:
Signed-off-by: Simon Glass <sjg@chromium.org>
When a uclass definition is missing, no drivers in that uclass can operate.
This can happen if a board has a strange collection of options (e.g. the
driver is enabled but the uclass is not).
Unfortunately this is very confusing at present. Starting up driver model
results in a -ENOENT error, which is pretty generic. Quite a big of digging
is needed to get to the root cause.
To help with this, change the error to a very strange one with no other
users in U-Boot. Also add a debug message.
Signed-off-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>
This is useful when we want to bind a device, but do not need the
pointer to the device.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
Add Kconfig entries for the simple-bus driver, both for U-Boot
and for SPL. The simple-bus is enabled by default in U-Boot and
disabled by default in SPL to preserve the original behavior.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
Modified to fit on top of Masahiro's $(SPL) setup:
Signed-off-by: Simon Glass <sjg@chromium.org>
This is a convenient way for a driver to get the hardware address of a
device, when regmap or syscon are not being used. Change existing callers
to use it as an example to others.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
The device might have already been probed during the call to
device_probe() on its parent device (e.g. PCI bridge devices).
In its parent device's probe routine, it might probe all of
its child devices via device_probe() thus the codes reenter
device_probe_child(). To support code reentrancy, test these
allocated memory against NULL to avoid memory leak, and return
to the caller if dev->flags has DM_FLAG_ACTIVATED set after
device_probe() returns, so that we don't mess up the device.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
We have flipped CONFIG_SPL_DISABLE_OF_CONTROL. We have cleansing
devices, $(SPL_) and CONFIG_IS_ENABLED(), so we are ready to clear
away the ugly logic in include/fdtdec.h:
#ifdef CONFIG_OF_CONTROL
# if defined(CONFIG_SPL_BUILD) && !defined(SPL_OF_CONTROL)
# define OF_CONTROL 0
# else
# define OF_CONTROL 1
# endif
#else
# define OF_CONTROL 0
#endif
Now CONFIG_IS_ENABLED(OF_CONTROL) is the substitute. It refers to
CONFIG_OF_CONTROL for U-boot proper and CONFIG_SPL_OF_CONTROL for
SPL.
Also, we no longer have to cancel CONFIG_OF_CONTROL in
include/config_uncmd_spl.h and scripts/Makefile.spl.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
We do not want to compile the DM remove code for SPL. Currently,
we undef it in include/config_uncmd_spl.h (for C files) and in
scripts/Makefile.uncmd_spl (for Makefiles). This is really ugly.
This commit demonstrates how we can deprecate those two files.
Use $(SPL_) for the entry in the Makfile and CONFIG_IS_ENABLED()
in C files.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Some devices are bound entirely by probing and do not have the benefit of
a device tree to give them a name. This is very common with PCI and USB. In
most cases this is fine, but we should add an official way to set a device
name. This should be called in the device's bind() method.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Currently, Devres requires additional 16 byte for each allocation,
which is not so insignificant in some cases.
Add CONFIG_DEVRES to make this framework optional.
If the option is disabled, devres functions fall back to
non-managed variants. For example, devres_alloc() to kzalloc(),
devm_kmalloc() to kmalloc(), etc.
Because devres_head is also surrounded by an ifdef conditional,
there is no memory overhead when CONFIG_DEVRES is disabled.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
In U-Boot's driver model, memory is basically allocated and freed
in the core framework. So, low level drivers generally only have
to specify the size of needed memory with .priv_auto_alloc_size,
.platdata_auto_alloc_size, etc. Nevertheless, some drivers still
need to allocate/free memory on their own in case they cannot
statically know the necessary memory size. So, I believe it is
reasonable enough to port Devres into U-boot.
Devres, which originates in Linux, manages device resources for each
device and automatically releases them on driver detach. With devres,
device resources are guaranteed to be freed whether initialization
fails half-way or the device gets detached.
The basic idea is totally the same to that of Linux, but I tweaked
it a bit so that it fits in U-Boot's driver model.
In U-Boot, drivers are activated in two steps: binding and probing.
Binding puts a driver and a device together. It is just data
manipulation on the system memory, so nothing has happened on the
hardware device at this moment. When the device is really used, it
is probed. Probing initializes the real hardware device to make it
really ready for use.
So, the resources acquired during the probing process must be freed
when the device is removed. Likewise, what has been allocated in
binding should be released when the device is unbound. The struct
devres has a member "probe" to remember when the resource was
allocated.
CONFIG_DEBUG_DEVRES is also supported for easier debugging.
If enabled, debug messages are printed each time a resource is
allocated/freed.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
Currently, we only have DM_FLAG_ACTIVATED to indicate the device
status, but we still cannot know in which stage is in progress,
binding or probing.
This commit introduces a new flag, DM_FLAG_BOUND, which is set when
the device is really bound, and cleared when it is unbound.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
The 'ranges' property can be used to specify a translation from the system
address to the bus address. Add support for this using the dev_get_addr()
function, which devices should use to find their address.
Signed-off-by: Simon Glass <sjg@chromium.org>
Currently, DM_FLAG_ACTIVATED is set twice; before calling
uclass_pre_probe_device() and again before calling drv->probe().
It looks like Simon's intention is the first one.
The DM_FLAG_ACTIVATED was moved twice, by commit 02eeb1bbb1
(dm: core: Mark device as active before calling its probe()
method), and then by commit 206d4d2b4b (dm: core: Mark device
as active before calling uclass probe() methods).
The first marking was added by the last move.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
In some rare cases it is useful to be able to locate a device given a device
tree node offset. An example is when you have an alias that points to a node
and you want to find the associated device. The device may be SPI, MMC or
something else, but you don't need to know the uclass to find it.
Add a function to do a global search for a device, given its device tree
offset.
Signed-off-by: Simon Glass <sjg@chromium.org>
Trivial bug fix for commit 5a87c4174d (dm: core: Drop device
removal error path when not supported).
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
When CONFIG_DM_DEVICE_REMOVE is not enabled, such as in SPL, we cannot
remove or unbind devices and do not expect to get errors when binding
and probing devices. So drop the error path to reduce code size.
Signed-off-by: Simon Glass <sjg@chromium.org>
In many cases SPL only uses a single serial port and there is no need for
alias sequence support. We will just use the serial port pointed to by
stdout-path in the /chosen node.
Signed-off-by: Simon Glass <sjg@chromium.org>
This commit extends the driver model device's API by function:
- dev_get_uclass_name()
And this function returns the device's uclass driver name if:
- given dev pointer, is non_NULL
otherwise, the NULL pointer is returned.
Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
This commit extends the driver model device's API by function:
- dev_get_driver_ops()
And this function returns the device's driver's operations if given:
- dev pointer, is non-NULL
- dev->driver->ops pointer, is non-NULL
in other case the, the NULL pointer is returned.
Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
This commit adds 'uclass_platdata' field to 'struct udevice', which
can be automatically allocated at bind. The allocation size is defined
in 'struct uclass_driver' as 'per_device_platdata_auto_alloc_size'.
New device's flag is added: DM_FLAG_ALLOC_UCLASS_PDATA, which is used
for memory freeing at device unbind method.
As for other udevice's fields, a complementary function is added:
- dev_get_uclass_platdata()
Signed-off-by: Przemyslaw Marczak <p.marczak@samsung.com>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Simon Glass <sjg@chromium.org>
Add some utility functions to check for children and for the last sibling in
a device's parent.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
The uclass pre-probe functions may end up calling back into the device in
some circumstances. This can fail if recursion takes place. Adjust the
ordering so that we mark the device as active early, then retract this
later if needed.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
The existing get_get_of_data() function provides access to both the driver's
compatible string and its driver data. However only the latter is actually
useful. Update the interface to reflect this and fix up existing users.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
The driver is not modified by driver model, so update driver_bind() to
recognise that.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Some driver want to put DMA buffers in their private data. Add a flag
to tell driver model to align driver-private data to a cache boundary so
that DMA will work correctly in this case.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Some uclasses want to set up a device before it is probed. Add a method
for this.
An example is with PCI, where a PCI uclass wants to set up its private
data for later use. This allows the device's uclass() method to make calls
whcih use that data (for example, read PCI memory regions from device
tree, set up bus numbers).
Signed-off-by: Simon Glass <sjg@chromium.org>
At present the device is not active when the probe() method is called. But
some probe() methods want to set up the device and this can involve
accessing it through normal methods. For example a PCI bus may wish to
set up its PCI parameters using calls to pci_hose_write_config_dword() and
similar.
At present this does not work because every such call within the probe()
method sees that the device is not active and attempts to probe it.
Already we mark the device as probed before calling the uclass post_probe()
method. This is a subtle change but I believe the new approach is better.
Since the scope of the change is only the probe() method and all its callees
it should still be within the control of the board author.
Signed-off-by: Simon Glass <sjg@chromium.org>
Add a convenience function to access the private data that a uclass stores
for each of its devices. Convert over most existing uses for consistency
and to provide an example for others.
Signed-off-by: Simon Glass <sjg@chromium.org>
Abstracting dev_get_addr can improve drivers that want to
get device's address.
Signed-off-by: Peng Fan <Peng.Fan@freescale.com>
Acked-by: Igor Grinberg <grinberg@compulab.co.il>
Acked-by: Simon Glass <sjg@chromium.org>
Some buses need to set up their devices before they can be used. This setup
may well be common to all buses in a particular uclass. Support a common
pre-probe method for the uclass, called before any bus devices are probed.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
In many cases the per-child private data for a device's children is defined
by the uclass rather than the individual driver. For example, a SPI bus
needs to store information about each of its children, but all SPI drivers
store the same information. It makes sense to allow the uclass to define
this data.
If the driver provides a size value for its per-child private data, then use
it. Failng that, fall back to that provided by the uclass.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
At present we try to use the 'reg' property and device tree aliases to give
devices a sequence number. The 'reg' property is often actually a memory
address, so the sequence numbers thus-obtained are not useful. It would be
better if the devices were just sequentially numbered in that case. In fact
neither I2C nor SPI use this feature, so drop it.
Some devices need us to look up an alias to number them within the uclass.
Add a flag to control this, so it is not done unless it is needed.
Adjust the tests to test this new behaviour.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
This is useful to check which uclass a device is in.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Allow parent drivers to be called when a new child is bound to them. This
allows a bus to set up information it needs for that child.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
In many cases the child platform data for a device's children is defined by
the uclass rather than the individual devices. For example, a SPI bus needs
to know the chip select and speed for each of its children. It makes sense
to allow this information to be defined the SPI uclass rather than each
individual driver.
If the device provides a size value for its child platdata, then use it.
Failng that, fall back to that provided by the uclass.
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
For buses it is common for parents to need to know the address of the child
on the bus, the bus speed to use for that child, and other information. This
can be provided in platform data attached to each child.
Add driver model support for this, including auto-allocation which can be
requested using a new property to specify the size of the data.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
When using allocated platform data, allocate it when we bind the device.
This makes it possible to fill in this information before the device is
probed.
This fits with the platform data model (when not using device tree),
since platform data exists at bind-time.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Make the error handling more standard to make it easier to build on top of
it. Also correct a bug in the error path where there is no parent.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Add dev_get_parent() as a convenience to obtain the parent of a device.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@ti.com>
Acked-by: Heiko Schocher <hs@denx.de>
When the device is created from a device tree node, it matches a compatible
string. Allow access to that string and the associated data.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@ti.com>
Acked-by: Heiko Schocher <hs@denx.de>
For SPL we don't expect to need to remove a device. Save some code space
by dropping this feature. The board config can define
CONFIG_DM_DEVICE_REMOVE if this is in fact needed.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@ti.com>
Buses sometimes want to pass data to their children when they are probed.
For example, a SPI bus may want to tell the slave device about the chip
select it is connected to.
Add a new function to permit the parent data to be supplied to the child.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
Buses need to iterate through their children in some situations. Add a few
functions to make this easy.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
Since dev->req_seq value is initialized from "reg" property of fdt node,
there is posibility, that address value contained in fdt is greater than
INT_MAX, and then value in dev->req_seq is negative which led to probe()
fail.
This patch fix this problem by ensuring that req_seq is positive, unless
it's one of errno codes.
Signed-off-by: Robert Baldyga <r.baldyga@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
The sequence number support in driver model requires device tree control.
It should be skipped if CONFIG_OF_CONTROL is not defined, and should not
require functions from fdtdec.
Signed-off-by: Simon Glass <sjg@chromium.org>
Some devices (particularly bus devices) must track their children, knowing
when a new child is added so that it can be set up for communication on the
bus.
Add a child_pre_probe() method to provide this feature, and a corresponding
child_post_remove() method.
Signed-off-by: Simon Glass <sjg@chromium.org>
Some device types can have child devices and want to store information
about them. For example a USB flash stick attached to a USB host
controller would likely use this space. The controller can hold
information about the USB state of each of its children.
The data is stored attached to the child device in the 'parent_priv'
member. It can be auto-allocated by dm when the child is probed. To
do this, add a per_child_auto_alloc_size value to the parent driver.
Signed-off-by: Simon Glass <sjg@chromium.org>
Devices can have childen that can be addressed by a simple index, the
sequence number or a device tree offset. Add functions to access a child
in each of these ways.
The index is typically used as a fallback when the sequence number is not
available. For example we may use a serial UART with sequence number 0 as
the console, but if no UART has sequence number 0, then we can fall back
to just using the first UART (index 0).
The device tree offset function is useful for buses, where they want to
locate one of their children. The device tree can be scanned to find the
offset of each child, and that offset can then find the device.
Signed-off-by: Simon Glass <sjg@chromium.org>
In U-Boot it is pretty common to number devices from 0 and access them
on the command line using this numbering. While it may come to pass that
we will move away from this numbering, the possibility seems remote at
present.
Given that devices within a uclass will have an implied numbering, it
makes sense to build this into driver model as a core feature. The cost
is fairly small in terms of code and data space.
With each uclass having numbered devices we can ask for SPI port 0 or
serial port 1 and receive a single device.
Devices typically request a sequence number using aliases in the device
tree. These are resolved when the device is probed, to deal with conflicts.
Sequence numbers need not be sequential and holes are permitted.
At present there is no support for sequence numbers using static platform
data. It could easily be added to 'struct driver_info' if needed, but it
seems better to add features as we find a use for them, and the use of -1
to mean 'no sequence' makes the default value somewhat painful.
Signed-off-by: Simon Glass <sjg@chromium.org>
Driver model currently only operates after relocation is complete. In this
state U-Boot typically has a small amount of memory available. In adding
support for driver model prior to relocation we must try to use as little
memory as possible.
In addition, on some machines the memory has not be inited and/or the CPU
is not running at full speed or the data cache is off. These can reduce
execution performance, so the less initialisation that is done before
relocation the better.
An immediately-obvious improvement is to only initialise drivers which are
actually going to be used before relocation. On many boards the only such
driver is a serial UART, so this provides a very large potential benefit.
Allow drivers to mark themselves as 'pre-reloc' which means that they will
be initialised prior to relocation. This can be done either with a driver
flag or with a 'dm,pre-reloc' device tree property.
To support this, the various dm scanning function now take a 'pre_reloc_only'
parameter which indicates that only drivers marked pre-reloc should be
bound.
Signed-off-by: Simon Glass <sjg@chromium.org>
using UBI and DM together leads in compiler error, as
both define a "struct device", so rename "struct device"
in include/dm/device.h to "struct udevice", as we use
linux code (MTD/UBI/UBIFS some USB code,...) and cannot
change the linux "struct device"
Signed-off-by: Heiko Schocher <hs@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Marek Vasut <marex@denx.de>
Add driver model functionality for generic board.
This includes data structures and base code for registering devices and
uclasses (groups of devices with the same purpose, e.g. all I2C ports will
be in the same uclass).
The feature is enabled with CONFIG_DM.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Marek Vasut <marex@denx.de>
Signed-off-by: Pavel Herrmann <morpheus.ibis@gmail.com>
Signed-off-by: Viktor Křivák <viktor.krivak@gmail.com>
Signed-off-by: Tomas Hlavacek <tmshlvck@gmail.com>
