This implements support for ioremapping of register windows that
encapsulate clock control registers used by a struct clk, with
transparent sibling inheritance.
Root clocks at the top of a given topology often encapsulate the entire
register space of all of their sibling clocks, so this mapping can be
done once and handed down. A given clock enable/disable case maps out to
a single bit in a shared register, so this prevents creating multiple
overlapping mappings.
The mapping case breaks down in to a couple of different situations:
- Sibling clocks without a specific mapping.
- Root clocks without a specific mapping.
- Any of sibling/root clocks with a specific mapping.
Sibling clocks with no specified mapping will grovel up the clock chain
and install the root clock mapping unconditionally at registration time.
Root clocks without their own mappings have a dummy BSS-initialized
mapping inserted that is handed down the chain just like any other
mapping. This permits all of the sibling clock ops to read/write using
the mapping offsets without any special configuration, enabling them to
not care whether access ultimately goes through translatable or
untranslatable memory.
Any clock with its own mapping will have the window initialized at
registration time and be ready for use by its clock ops. Failure to
establish the mapping will prevent registration, so no additional sanity
checks are needed. Sibling clocks that double as parents for the moment
will not propagate their mapping down, but this is easily tunable if the
need arises.
All clock mappings are kref refcounted, with each instance of mapping
inheritance incrementing the refcount.
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Remove "name" and "id" from drivers/sh/ struct clk.
The struct clk members "name" and "id" are not used
now when matching is done through clkdev.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add support for reparenting of div6 clocks on SuperH and SH-Mobile SoCs.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Many system clocks can select a parent by writing a value to a specific field
in the configuration register. Add a list of parents and location and width of
the source selection field in the clock configuration register to struct clk to
assist in clk_set_parent() implementation.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Now that the definitions have been consolidated in an alternate header,
update the template accordingly.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch is V2 of the SH clock framework move from
arch/sh/kernel/cpu/clock.c to drivers/sh/clk.c. All
code except the following functions are moved:
clk_init(), clk_get() and clk_put().
The init function is still kept in clock.c since it
depends on the SH-specific machvec implementation.
The symbols clk_get() and clk_put() already exist in
the common ARM clkdev code, those symbols are left in
the SH tree to avoid duplicating them for SH-Mobile ARM.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch is V2 of the clock framework move from
arch/sh/include/asm/clock.h to include/linux/sh_clk.h
and updates the include paths for files that will be
shared between SH and SH-Mobile ARM.
The file asm/clock.h is still kept in this version,
this to depend on as few files as possible at this
point. We keep SH specific stuff in there.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Paul Mundt