Similar to the existing reg_downshift mechanism, that is used to
translate register addresses on busses that have a smaller address
stride, it's also possible to want to upshift register addresses.
Such a case was encountered when network PHYs and PCS that usually sit
on a MDIO bus (16-bits register with a stride of 1) are integrated
directly as memory-mapped devices. Here, the same register layout
defined in 802.3 is used, but the register now have a larger stride.
Introduce a mechanism to also allow upshifting register addresses.
Re-purpose reg_downshift into a more generic, signed reg_shift, whose
sign indicates the direction of the shift. To avoid confusion, also
introduce macros to explicitly indicate if we want to downshift or
upshift.
For bisectability, change any use of reg_downshift to use reg_shift.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Tested-by: Colin Foster <colin.foster@in-advantage.com>
Link: https://lore.kernel.org/r/20230407152604.105467-1-maxime.chevallier@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Merge series from William Breathitt Gray <william.gray@linaro.org>:
The regmap API supports IO port accessors so we can take advantage of
regmap abstractions rather than handling access to the device registers
directly in the driver.
A patch to pass irq_drv_data as a parameter for struct regmap_irq_chip
set_type_config() is included. This is needed by the
idio_24_set_type_config() and ws16c48_set_type_config() callbacks in
order to update the type configuration on their respective devices.
The current state of the art for sparse register maps is the
rbtree cache. This works well for most applications but isn't
always ideal for sparser register maps since the rbtree can get
deep, requiring a lot of walking. Fortunately the kernel has a
data structure intended to address this very problem, the maple
tree. Provide an initial implementation of a register cache
based on the maple tree to start taking advantage of it.
The entries stored in the maple tree are arrays of register
values, with the maple tree keys holding the register addresses.
We store data in host native format rather than device native
format as we do for rbtree, this will be a benefit for devices
where we don't marshal data within regmap and simplifies the code
but will result in additional CPU overhead when syncing the cache
on devices where we do marshal data in regmap.
This should work well for a lot of devices, though there's some
additional areas that could be looked at such as caching the
last accessed entry like we do for rbtree and trying to minimise
the maple tree level locking. We should also use bulk writes
rather than single register writes when resyncing the cache where
possible, even if we don't store in device native format.
Very small register maps may continue to to better with rbtree
longer term.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230325-regcache-maple-v3-2-23e271f93dc7@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>
The compressed register cache support has assumptions that make it hard to
cover in testing, mainly that it requires raw registers defaults be
provided. Rather than either address these assumptions or leave it untested
by the forthcoming KUnit tests let's remove it, the use case is quite thin
and there are no current users.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230324-regcache-lzo-v1-1-08c5d63e2a5e@kernel.org
Merge series from William Breathitt Gray <william.gray@linaro.org>:
There are devices which have interrupt support with mask and ack
registers but no status register. Add a flag which lets us support
them, we just assume that all the interrupts fired.
The MDIO subsystem is getting rid of MII_ADDR_C45 and thus also
encoding associated encoding of the C45 device address and register
address into one value. regmap-mdio also uses this encoding for the
C45 bus.
Move to the new C45 helpers for MDIO access and provide regmap-mdio
helper macros.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20230116111509.4086236-1-michael@walle.cc
Signed-off-by: Mark Brown <broonie@kernel.org>
Merge series from Eddie James <eajames@linux.ibm.com>:
The SBEFIFO hardware can now be attached over a new I2C endpoint interface
called the I2C Responder (I2CR). In order to use the existing SBEFIFO
driver, add a regmap driver for the FSI bus and an endpoint driver for the
I2CR. Then, refactor the SBEFIFO and OCC drivers to clean up and use the
new regmap driver or the I2CR interface.
This branch just has the regmap change so it can be shared with the FSI
code.
Several architectures have accelerated operations for MMIO
operations writing to a single register, such as writesb, writesw,
writesl, writesq, readsb, readsw, readsl and readsq but regmap
currently cannot use them because we have no hooks for providing
an accelerated noinc back-end for MMIO.
Solve this by providing reg_[read/write]_noinc callbacks for
the bus abstraction, so that the regmap-mmio bus can use this.
Currently I do not see a need to support this for custom regmaps
so it is only added to the bus.
Callbacks are passed a void * with the array of values and a
count which is the number of items of the byte chunk size for
the specific register width.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220816204832.265837-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>
