Prepare v2026.01-rc3

The asserts in ut.h are often used. Provide online documentation.

Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

Let's introduce the Generic System Interconnect subsystem based on
the counterpart Linux framework which is used to vote for bandwidth
across multiple SoC busses.

Documentation for the Linux Generic System Interconnect Subsystem can
be found at [1].

Each bus endpoints are materialised as "nodes" which are linked together,
and the DT will specify a pair of nodes to enable and set a bandwidth
on the route between those endpoints.

The hardware resources that provide those nodes and provides the way
to vote for the bandwidth are called "providers".

The Interconnect uclass code is heavily based on the Linux one, with
some small differences:
- nodes are allocated as udevices instead of Linux idr_alloc()
- tag management is minimal, only normal xlate is supported
- getting nodes states at probe is not implemented
- providers are probed on demand while the nodes links are traversed
- nodes are populated on bind
- id management is simplified, static IDs and dynamics IDs can be used
- identical consume API as Linux, only implementation differs

Fully tested with associated DM test suite.

[1] https://docs.kernel.org/driver-api/interconnect.html

Link: https://patch.msgid.link/20251120-topic-interconnect-next-v5-1-e8a82720da5d@linaro.org
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>

Enable i3c general uclass driver. This uclass driver will have
genaral read and write api to call the specific i3c driver.

Signed-off-by: Dinesh Maniyam <dinesh.maniyam@altera.com>

The LMB module has undergone significant changes in the recent
past. Add a document which briefly describes what the LMB module does,
and the changes that have been made to it's design since the 2025.01
release.

Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Add a new internal API called uthread (Kconfig symbol: UTHREAD) which
provides cooperative multi-tasking. The goal is to be able to improve
the performance of some parts of U-Boot by overlapping lengthy
operations, and also implement background jobs in the U-Boot shell.
Each uthread has its own stack allocated on the heap. The default stack
size is defined by the UTHREAD_STACK_SIZE symbol and is used when
uthread_create() receives zero for the stack_sz argument.

The implementation is based on context-switching via initjmp()/setjmp()/
longjmp() and is inspired from barebox threads [1]. A notion of thread
group helps with dependencies, such as when a thread needs to block
until a number of other threads have returned.

The name "uthread" comes from "user-space threads" because the
scheduling happens with no help from a higher privileged mode, contrary
to more complex models where kernel threads are defined. But the 'u'
may as well stand for 'U-Boot' since the bootloader may actually be
running at any privilege level and the notion of user vs. kernel may
not make much sense in this context.

[1] https://github.com/barebox/barebox/blob/master/common/bthread.c

Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Add the HAVE_INIJMP symbol to be set by architectures that support
initjmp(), a non-standard extension to setjmp()/longjmp() allowing to
initialize a jump buffer with a function pointer and a stack pointer.
This will be useful to later introduce threads. With this new function
it becomes possible to longjmp() to a particular function pointer
(rather than to a point previously reached during program execution as
is the case with setjmp()), and with a custom stack. Both things are
needed to spin off a new thread. Then the usual setjmp()/longjmp() pair
is enough to save and restore a context, i.e., switch thread.

Add the initjmp() prototype to <include/setjmp.h> since it is common to
all architectures.

Add an entry to the API documentation: doc/api/setjmp.rst.

Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

Add include/fs.h to the API documentation.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

Introduce simple led.rst documentation to document all the additional
Kconfig and the current limitation of LED_BLINK and GPIO software blink.

Also add missing definition for sw_blink in led_uc_plat struct.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

Move to the new documentation style with rST formatting.

Signed-off-by: Vasileios Amoiridis <vasileios.amoiridis@cern.ch>