coresight: Add a helper for getting csdev->mode

Now that mode is in struct coresight_device accesses can be wrapped.

Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20240129154050.569566-12-james.clark@arm.com
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>

coresight: Move mode to struct coresight_device

Most devices use mode, so move the mode definition out of the individual
devices and up to the Coresight device. This will allow the core code to
also know the mode which will be useful in a later commit.

This also fixes the inconsistency of the documentation of the mode field
on the individual device types. For example ETB10 had "this ETB is being
used".

Two devices didn't require an atomic mode type, so these usages have
been converted to atomic_get() and atomic_set() only to make it compile,
but the documentation of the field in struct coresight_device explains
this type of usage.

In the future, manipulation of the mode could be completely moved out of
the individual devices and into the core code because it's almost all
duplicate code, and this change is a step towards that.

Signed-off-by: James Clark <james.clark@arm.com>
Link: https://lore.kernel.org/r/20240129154050.569566-5-james.clark@arm.com
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>

coresight: Fix uninitialized struct warnings

These warnings would be hit with the following W=1 build change so
initialize all structs properly.

Signed-off-by: James Clark <james.clark@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20231123120459.287578-2-james.clark@arm.com

coresight: tmc: Make etr buffer mode user configurable from sysfs

Currently TMC-ETR automatically selects the buffer mode from all available
methods in the following sequentially fallback manner - also in that order.

1. FLAT mode with or without IOMMU
2. TMC-ETR-SG (scatter gather) mode when available
3. CATU mode when available

But this order might not be ideal for all situations. For example if there
is a CATU connected to ETR, it may be better to use TMC-ETR scatter gather
method, rather than CATU. But hard coding such order changes will prevent
us from testing or using a particular mode. This change provides following
new sysfs tunables for the user to control TMC-ETR buffer mode explicitly,
if required. This adds following new sysfs files for buffer mode selection
purpose explicitly in the user space.

/sys/bus/coresight/devices/tmc_etr<N>/buf_modes_available
/sys/bus/coresight/devices/tmc_etr<N>/buf_mode_preferred

$ cat buf_modes_available
auto flat tmc-sg catu ------------------> Supported TMC-ETR buffer modes

$ echo catu > buf_mode_preferred -------> Explicit buffer mode request

But explicit user request has to be within supported ETR buffer modes only.
These sysfs interface files are exclussive to ETR, and hence these are not
available for other TMC devices such as ETB or ETF etc.

A new auto' mode (i.e ETR_MODE_AUTO) has been added to help fallback to the
existing default behaviour, when user provided preferred buffer mode fails.
ETR_MODE_FLAT and ETR_MODE_AUTO are always available as preferred modes.

Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: James Clark <james.clark@arm.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
[Fixup year in sysfs ABI documentation]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230818082112.554638-1-anshuman.khandual@arm.com

coresight: tmc: Don't enable TMC when it's not ready.

If TMC ETR is enabled without being ready, in later use we may
see AXI bus errors caused by accessing invalid addresses.

Signed-off-by: Yabin Cui <yabinc@google.com>
[ Tweak error message ]
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20230127231001.1920947-1-yabinc@google.com

coresight: Re-use same function for similar sysfs register accessors

Currently each accessor macro creates an identical function which wastes
space in the text area and pollutes the ftrace function names. Change it
so that the same function is used, but the register to access is passed
in as parameter rather than baked into each function.

Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220830172614.340962-4-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

coresight: Simplify sysfs accessors by using csdev_access abstraction

The coresight_device struct is available in the sysfs accessor, and this
contains a csdev_access struct which can be used to access registers.
Use this instead of passing in the type of each drvdata so that a common
function can be shared between all the cs drivers.

No functional changes.

Signed-off-by: James Clark <james.clark@arm.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20220830172614.340962-3-james.clark@arm.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

coresight: tmc: Configure AXI write burst size

The current driver sets the write burst size initiated by TMC-ETR on
AXI bus to a fixed value of 16. Make this configurable by reading the
value specified in fwnode. If not specified, then default to 16.

Introduced a "max_burst_size" variable in tmc_drvdata structure to
facilitate this change.

Signed-off-by: Tanmay Jagdale <tanmay@marvell.com>
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Link: https://lore.kernel.org/r/20210901131049.1365367-3-tanmay@marvell.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

coresight: Convert coresight_timeout to use access abstraction

Convert the generic routines to use the new access abstraction layer
gradually, starting with coresigth_timeout.

Link: https://lore.kernel.org/r/20210110224850.1880240-6-suzuki.poulose@arm.com
Cc: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210201181351.1475223-8-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: Introduce device access abstraction

We are about to introduce support for sysreg access to ETMv4.4+
component. Since there are generic routines that access the
registers (e.g, CS_LOCK/UNLOCK , claim/disclaim operations, timeout)
and in order to preserve the logic of these operations at a
single place we introduce an abstraction layer for the accesses
to a given device.

Link: https://lore.kernel.org/r/20210110224850.1880240-4-suzuki.poulose@arm.com
Cc: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210201181351.1475223-6-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

amba: Make the remove callback return void

All amba drivers return 0 in their remove callback. Together with the
driver core ignoring the return value anyhow, it doesn't make sense to
return a value here.

Change the remove prototype to return void, which makes it explicit that
returning an error value doesn't work as expected. This simplifies changing
the core remove callback to return void, too.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org> # for drivers/memory
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com> # for hwtracing/coresight
Acked-By: Vinod Koul <vkoul@kernel.org> # for dmaengine
Acked-by: Guenter Roeck <linux@roeck-us.net> # for watchdog
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Takashi Iwai <tiwai@suse.de> # for sound
Acked-by: Vladimir Zapolskiy <vz@mleia.com> # for memory/pl172
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210126165835.687514-5-u.kleine-koenig@pengutronix.de
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

coresight: remove broken __exit annotations

Functions that are annotated __exit are discarded for built-in drivers,
but the .remove callback in a device driver must still be kept around
to allow bind/unbind operations.

There is now a linker warning for the discarded symbol references:

`tmc_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-tmc-core.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-tmc-core.o
`tpiu_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-tpiu.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-tpiu.o
`etb_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-etb10.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-etb10.o
`static_funnel_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-funnel.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-funnel.o
`dynamic_funnel_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-funnel.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-funnel.o
`static_replicator_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-replicator.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-replicator.o
`dynamic_replicator_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-replicator.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-replicator.o
`catu_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-catu.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-catu.o

Remove all those annotations.

Fixes: 8b0cf82677d1 ("coresight: stm: Allow to build coresight-stm as a module")
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20201208182651.1597945-3-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

coresight: tmc: Allow tmc to be built as a module

Allow to build coresight-tmc as a module, for ease of development.

- Kconfig becomes a tristate, to allow =m
- append -core to source file name to allow module to
be called coresight-tmc by the Makefile
- add an tmc_remove function, for module unload
- add a MODULE_DEVICE_TABLE for autoloading on boot

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@armlinux.org.uk>
Tested-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200928163513.70169-14-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>