Commit graph

34 commits

Author SHA1 Message Date
Bin Meng
1a6bd4717f dm: doc: Update description of pre-relocation support
Add some description about pre-relocation driver binding, including
usage of DM_FLAG_PRE_RELOC flag and caveats.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2018-11-14 09:16:28 -08:00
Simon Glass
06f94461a9 fdt: Allow indicating a node is for U-Boot proper only
At present it is not possible to specify that a node should be used before
relocation (in U-Boot proper) without it also ending up in SPL and TPL
device trees. Add a new "u-boot,dm-pre-proper" boolean property for this.

Signed-off-by: Simon Glass <sjg@chromium.org>
2018-10-09 04:40:27 -06:00
Simon Glass
a15a7aa47b doc: Update docs for device tree in SPL, TPL
Make a few small updates to indicate that device tree can be used in SPL
and TPL.

Signed-off-by: Simon Glass <sjg@chromium.org>
2018-10-09 04:40:27 -06:00
Tom Rini
15416c86b4 dm: Update README.txt to clarify device tree usage
In the section about Device Trees add a paragraph at the end that
clarifies how we decide of a tree is valid or not.  We say that all
bindings must either be in the specification (link provided) or in our
device-tree-bindings directory.  We say that most of these come from the
Linux Kernel and as such some design decisions are made for us already,
but that in most cases we wish to retain compatibility.

Cc: Simon Glass <sjg@chromium.org>
Cc: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2018-09-25 21:49:18 -04:00
Chris Packham
09b8d67f31 doc: driver-model: Fix typo
Signed-off-by: Chris Packham <judge.packham@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2018-07-26 14:18:38 -06:00
Heiko Stübner
27326c7ee2 dm: allow limiting pre-reloc markings to spl or tpl
Right now the u-boot,dm-pre-reloc flag will make each marked node
always appear in both spl and tpl. But systems needing an additional
tpl might have special constraints for each, like the spl needing to
be very tiny.

So introduce two additional flags to mark nodes for only spl or tpl
environments and introduce a function dm_fdt_pre_reloc to automate
the necessary checks in code instances checking for pre-relocation
flags.

The behaviour of the original flag stays untouched and still marks
a node for both spl and tpl.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Kever Yang <kever.yang@rock-chips.com>
2017-03-16 16:03:44 -06:00
Simon Glass
e160f7d430 dm: core: Replace of_offset with accessor
At present devices use a simple integer offset to record the device tree
node associated with the device. In preparation for supporting a live
device tree, which uses a node pointer instead, refactor existing code to
access this field through an inline function.

Signed-off-by: Simon Glass <sjg@chromium.org>
2017-02-08 06:12:14 -07:00
Stephen Warren
daac3bfee5 dm: allow setting driver_data before/during bind
This will allow a driver's bind function to use the driver data. One
example is the Tegra186 GPIO driver, which instantiates child devices
for each of its GPIO ports, yet supports two different HW instances each
with a different set of ports, and identified by the udevice_id .data
field.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
2016-05-26 20:48:31 -06:00
Jagan Teki
e57f9c8eef doc: driver-model: Update dm tests run using test.py
Since all the tests are implemented in pytest infrastructure,
So update the dm tests with the same instead of ./test/dm/test-dm.sh

Cc: Tom Rini <trini@konsulko.com>
Cc: Simon Glass <sjg@chromium.org>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Jagan Teki <jteki@openedev.com>
2016-04-14 11:51:39 -06:00
Simon Glass
97f3ee34b6 dm: Add platform data advice and admonishment
We should guide people more strongly towards device tree to avoid the
proliferation of platform data structures. Add documentation to the driver
model README, and also the platform data header file.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:30 -06:00
Simon Glass
98a1605309 dm: Update the README to reflect the current test output
There are a lot more tests now. To avoid confusion add the updated test
output to the driver model README.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
2015-04-22 11:15:02 -06:00
Simon Glass
2017aaef8c dm: Update documentation for new bus features
Now that we have new bus features, update README.txt and the SPI docs to
explain these.
Signed-off-by: Simon Glass <sjg@chromium.org>
2015-01-29 17:09:57 -07:00
Simon Glass
9cc36a2b89 dm: core: Add a flag to control sequence numbering
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>
2015-01-29 17:09:55 -07:00
Simon Glass
2f3b95dbc7 dm: core: Set device tree node for root device
The root device corresponds to the root device tree node, so set this up.
Also add a few notes to the documentation.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-01-29 17:09:54 -07:00
Masahiro Yamada
33fcd1bbd5 dm: README: recommend u-boot.dtb to try driver-model on sandbox
To enjoy driver-model on sandbox, using device tree is recommended.
While we are here, change sandbox_config to sandbox_defconfig too.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Simon Glass <sjg@chromium.org>
Acked-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2015-01-05 17:45:15 -07:00
Simon Glass
38687ae676 dm: Update documentation to include CONFIG_DM... options
Add documentation for the various driver model options that are now
available.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-11-21 08:14:27 +01:00
Simon Glass
4324174d03 test: dm: Add additional GPIO tests
Add tests for gpio_requestf() and for memory leaks.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-10-23 19:29:53 -06:00
Simon Glass
d44f597b12 dm: gpio: Add gpio_requestf() helper for printf() strings
Add a helper which permits a printf()-style format string for the requester
string.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-10-23 19:29:52 -06:00
Simon Glass
4b8f11c2cc test: dm: Update GPIO tests for new gpio_request() method
Now that gpio_request() is handled by the uclass, updates the tests
accordingly.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-10-23 19:29:52 -06:00
Simon Glass
547cea19b8 dm: core: Add a clarifying comment on struct udevice's seq member
The sequence number is unique within the uclass, so state this clearly.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
2014-10-22 10:36:46 -06:00
Simon Glass
a8981d4f80 dm: core: Add functions for iterating through device children
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>
2014-10-22 10:36:45 -06:00
Simon Glass
a327dee0f4 dm: Add child_pre_probe() and child_post_remove() methods
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>
2014-07-23 14:08:37 +01:00
Simon Glass
e59f458de6 dm: Introduce per-child data for devices
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>
2014-07-23 14:08:37 +01:00
Simon Glass
997c87bb0b dm: Add functions to access a device's children
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>
2014-07-23 14:08:37 +01:00
Simon Glass
1ca7e2062b dm: Provide a function to scan child FDT nodes
At present only root nodes in the device tree are scanned for devices.
But some devices can have children. For example a SPI bus may have
several children for each of its chip selects.

Add a function which scans subnodes and binds devices for each one. This
can be used for the root node scan also, so change it.

A device can call this function in its bind() or probe() methods to bind
its children.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-07-23 14:08:36 +01:00
Simon Glass
c910e2e2da dm: Avoid accessing uclasses before they are ready
Don't allow access to uclasses before they have been initialised.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-07-23 14:07:26 +01:00
Simon Glass
f4cdead24a dm: Allow a device to be found by its FDT offset
Each device that was bound from a device tree has an node that caused it to
be bound. Add functions that find and return a device based on a device tree
offset.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-07-23 14:07:25 +01:00
Simon Glass
5a66a8ff86 dm: Introduce device sequence numbering
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>
2014-07-23 14:07:25 +01:00
Simon Glass
00606d7e39 dm: Allow drivers to be marked 'before relocation'
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>
2014-07-23 14:07:24 +01:00
Simon Glass
22ec136325 dm: Expand and improve the device lifecycle docs
The lifecycle of a device is an important part of driver model. Add to the
existing documentation and clarify it.

Reported-by: Jon Loeliger <jdl@jdl.com>

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-06-20 11:56:53 -06:00
Simon Glass
ae7f451308 dm: Rename struct device_id to udevice_id
It is best to avoid having any occurence of 'struct device' in driver
model, so rename to achieve this.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-06-20 11:55:18 -06:00
Chris Packham
34e4a2ec0a docs: driver-model: Fix spelling
Signed-off-by: Chris Packham <judge.packham@gmail.com>
2014-06-11 16:27:05 -04:00
Heiko Schocher
54c5d08a09 dm: rename device struct to udevice
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>
2014-05-27 10:21:32 -04:00
Simon Glass
65c70539e5 dm: Add README for driver model
This adds a README to help with understanding of this series.

Signed-off-by: Simon Glass <sjg@chromium.org>
2014-03-04 12:15:29 -05:00