Use this new Kconfig to simplify the compilation conditions where
appropriate.

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

At present it is possible to call uclass_get() before driver model is
inited. In fact this happens on x86 boards which use Intel FSPv1, since
mrccache_get_region() tries to get the SPI flash device very early
during init.

This has always been undefined behaviour. Previously it generally worked,
i.e. returned an error code without crashing, because gd->uclass_root_s
is zeroed and the uclass can be added despite driver model not being
ready, due to the way lists are implemented. With the change to use a
gd->uclass_root pointer, this no-longer works. For example, it causes a
hang on minnowmax.

Fix this by adding a check that driver model is ready when uclass_get() is
called. This function is called in the process of locating any device, so
it is a good place to add the check.

This fixes booting on minnowmax.

Signed-off-by: Simon Glass <sjg@chromium.org>
Fixes: 8a715530bb1 ("dm: core: Allow the uclass list to move")

At present this function is included in the build but with of-platdata it
only services to produce a confusing link error complaining about a call
to dev_read_u32_default().

Drop it so that any call to uclass_find_device_by_phandle() is flagged as
an error, making it easier to see what is going on.

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

There is no need to ever add new uclasses since these are set up at build
time. Update the code to return an error if this is attempted.

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

Move this out of the common header and include it only where needed.  In
a number of cases this requires adding "struct udevice;" to avoid adding
another large header or in other cases replacing / adding missing header
files that had been pulled in, very indirectly.   Finally, we have a few
cases where we did not need to include <asm/global_data.h> at all, so
remove that include.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Rini <trini@konsulko.com>

Support a common method to probe all devices associated with uclass.

This includes data structures and code for finding the first device and
looping for remaining devices associated with uclasses (groups of devices
with the same purpose, e.g. all SERIAL ports will be in the same uclass).

An example is SBSA compliant PL011 UART IP, where firmware does the serial
port initialization and prepare uart device to let the kernel use it for
sending and reveiving the characters.SERIAL uclass will use this function
to initialize PL011 UART ports.

The feature is enabled with CONFIG_DM.

Signed-off-by: Vabhav Sharma <vabhav.sharma@nxp.com>
Reviewed-by: Stefan Roese <sr@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Sean Anderson <seanga2@gmail.com>

At present the uclass list head is in global_data. This is convenient
but with the new of-platdata we need the list head to be declared by
the generated code.

Change this over to be a pointer. Provide a 'static' version in
global_data to retain the current behaviour.

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

Now that the sequence-numbering migration is complete, rename this member
back to seq_, adding an underscore to indicate it is internal to driver
model.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

These are supposed to be private to driver model, not accessed by any code
outside. Add a trailing underscore to indicate this.

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

Use these functions in the core code as much as possible. With this, there
are only two places where each priv/plat pointer is accessed, one for read
and one for write.

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