Commit Graph

6 Commits

Author SHA1 Message Date
Masahiro Yamada
e151a1c288 syscon: add Linux-compatible syscon API
The syscon implementation in U-Boot is different from that in Linux.
Thus, DT files imported from Linux do not work for U-Boot.

In U-Boot driver model, each node is bound to a dedicated driver
that is the most compatible to it.  This design gets along with the
concept of DT, and the syscon in Linux originally worked like that.

However, Linux commit bdb0066df96e ("mfd: syscon: Decouple syscon
interface from platform devices") changed the behavior because it is
useful to let a device bind to another driver, but still work as a
syscon provider.

That change had happened before U-Boot initially supported the syscon
driver by commit 6f98b7504f ("dm: Add support for generic system
controllers (syscon)").  So, the U-Boot's syscon works differently
from the beginning.  I'd say this is mis-implementation given that
DT is not oriented to a particular project, but Linux is the canon
of DT in practice.

The problem typically arises in the combination of "syscon" and
"simple-mfd" compatibles.

In Linux, they are orthogonal, i.e., the order between "syscon" and
"simple-mfd" does not matter at all.

Assume the following compatible.

   compatible = "foo,bar-syscon", "syscon", "simple-mfd";

In U-Boot, this device node is bound to the syscon driver
(driver/core/syscon-uclass.c) since the "syscon" is found to be the
most compatible.  Then, syscon_get_regmap() succeeds.

However,

   compatible = "foo,bar-syscon", "simple-mfd", "syscon";

does not work because this node is bound to the simple-bus driver
(drivers/core/simple-bus.c) in favor of "simple-mfd" compatible.
The compatible string "syscon" is just dismissed.

Moreover,

   compatible = "foo,bar-syscon", "syscon";

works like the first case because the syscon driver populates the
child devices.  This is wrong because populating children is the job
of "simple-mfd" (or "simple-bus").

This commit ports syscon_node_to_regmap() from Linux.  This API
does not require the given node to be bound to a driver in any way.

Reported-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-07 15:49:52 -04:00
Tom Rini
83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00
Simon Glass
c20ee0ed07 dtoc: Add support for 32 or 64-bit addresses
When using 32-bit addresses dtoc works correctly. For 64-bit addresses it
does not since it ignores the #address-cells and #size-cells properties.

Update the tool to use fdt64_t as the element type for reg properties when
either the address or size is larger than one cell. Use the correct value
so that C code can obtain the information from the device tree easily.

Alos create a new type, fdt_val_t, which is defined to either fdt32_t or
fdt64_t depending on the word size of the machine. This type corresponds
to fdt_addr_t and fdt_size_t. Unfortunately we cannot just use those types
since they are defined to phys_addr_t and phys_size_t which use
'unsigned long' in the 32-bit case, rather than 'unsigned int'.

Add tests for the four combinations of address and size values (32/32,
64/64, 32/64, 64/32). Also update existing uses for rk3399 and rk3368
which now need to use the new fdt_val_t type.

Signed-off-by: Simon Glass <sjg@chromium.org>

Suggested-by: Heiko Stuebner <heiko@sntech.de>
Reported-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Tested-by: Kever Yang <kever.yang@rock-chips.com>
2017-09-15 05:27:38 -06:00
Simon Glass
04ecf36ba6 dm: syscon: Add support for of-platdata
Provide a new function which can cope with obtaining information from
of-platdata instead of the device tree.

Signed-off-by: Simon Glass <sjg@chromium.org>
2016-07-14 20:40:24 -06:00
Simon Glass
ac94b7bcbe dm: syscon: Allow finding devices by driver data
We have a way to find a regmap by its syscon driver data value. Add the same
for syscon itself.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
2016-01-24 12:07:19 +08:00
Simon Glass
5725128507 dm: Add support for generic system controllers (syscon)
Many SoCs have a number of system controllers which are dealt with as a
group by a single driver. It is a pain to have to add lots of compatible
strings and/or separate drivers for each. Instead we can identify the
controllers by a number and request the address of the one we want.

Add a simple implementation of this which can be used by SoC driver code.

Signed-off-by: Simon Glass <sjg@chromium.org>
2015-07-21 17:39:24 -06:00