linux-toradex.git/drivers/clocksource/exynos_mct.c, branch v6.0-rc4

clocksource/drivers/exynos_mct: Increase the size of name array

2022-03-07T17:27:22+00:00

Variable _name_ hold mct_tick number per cpu and it is currently
limited to 10. Which restrict the scalability of the MCT driver for
the SoC which has more local timers interrupts (>= 12).
Increase the length of it to make mct_tick printed correctly for
each local timer interrupts per CPU.

Signed-off-by: Alim Akhtar 
Reviewed-by: Krzysztof Kozlowski 
Link: https://lore.kernel.org/r/20220221174547.26176-3-alim.akhtar@samsung.com
Signed-off-by: Daniel Lezcano

clocksource/drivers/exynos_mct: Bump up mct max irq number

2022-03-07T17:27:22+00:00

Bump-up maximum number of MCT IRQ to match the binding
documentation. This make driver scalable for SoC which
has more than 12 timer irqs, like recently added FSD SoC.

Reviewed-by: Krzysztof Kozlowski 
Signed-off-by: Alim Akhtar 
Link: https://lore.kernel.org/r/20220221174547.26176-2-alim.akhtar@samsung.com
Signed-off-by: Daniel Lezcano

clocksource/drivers/exynos_mct: Remove mct interrupt index enum

2022-03-07T17:27:22+00:00

MCT driver define an enum which list global and local timer's
irq index. Most of them are not used but MCT_G0_IRQ and
MCT_L0_IRQ and these two are at a fixed offset/index.
Get rid of this enum and use a #define for the used irq index.

No functional changes expected.

Reviewed-by: Krzysztof Kozlowski 
Signed-off-by: Alim Akhtar 
Link: https://lore.kernel.org/r/20220221174547.26176-1-alim.akhtar@samsung.com
Signed-off-by: Daniel Lezcano

clocksource/drivers/exynos_mct: Handle DTS with higher number of interrupts

2022-03-07T17:27:22+00:00

The driver statically defines maximum number of interrupts it can
handle, however it does not respect that limit when configuring them.
When provided with a DTS with more interrupts than assumed, the driver
will overwrite static array mct_irqs leading to silent memory
corruption.

Validate the interrupts coming from DTS to avoid this.  This does not
change the fact that such DTS might not boot at all, because it is
simply incompatible, however at least some warning will be printed.

Fixes: 36ba5d527e95 ("ARM: EXYNOS: add device tree support for MCT controller driver")
Signed-off-by: Krzysztof Kozlowski 
Reviewed-by: Alim Akhtar 
Link: https://lore.kernel.org/r/20220220103815.135380-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Daniel Lezcano

clocksource/drivers/exynos_mct: Fix silly typo resulting in checkpatch warning

2021-12-09T11:29:52+00:00

Commit ae460fd9164b ("clocksource/drivers/exynos_mct: Prioritise Arm
arch timer on arm64") changed the rating of the MCT clockevents device
to be lower than the Arm architected timer and, in the process, replaced
a semicolon with a comma thanks to a silly copy-paste error.

Put the semicolon back so that the code looks more idiomatic and resolve
the SUSPECT_COMMA_SEMICOLON warning from checkpatch at the same time.

Cc: Krzysztof Kozlowski 
Cc: Daniel Lezcano 
Signed-off-by: Will Deacon 
Reviewed-by: Krzysztof Kozlowski 
Link: https://lore.kernel.org/r/20211103164804.30182-1-will@kernel.org
Signed-off-by: Daniel Lezcano

clocksource/drivers/exynos_mct: Refactor resources allocation

2021-11-16T15:12:00+00:00

Move interrupts allocation from exynos4_timer_resources() into separate
function together with the interrupt number parsing code from
mct_init_dt(), so the code for managing interrupts is kept together.
While touching exynos4_timer_resources() function, move of_iomap() to it.
No functional changes.

Signed-off-by: Marek Szyprowski 
Reviewed-by: Chanwoo Choi 
Tested-by: Chanwoo Choi 
Reviewed-by: Krzysztof Kozlowski 
Signed-off-by: Sam Protsenko 
Link: https://lore.kernel.org/r/20211101193531.15078-2-semen.protsenko@linaro.org
Signed-off-by: Daniel Lezcano

clocksource/drivers/exynos_mct: Mark MCT device as CLOCK_EVT_FEAT_PERCPU

2021-08-13T07:24:22+00:00

The "mct_tick" is a per-cpu clockevents device. Set the
CLOCK_EVT_FEAT_PERCPU feature to prevent e.g. mct_tick0 being unsafely
designated as the global broadcast timer and instead treat the device as
a per-cpu wakeup timer.

Cc: Daniel Lezcano 
Cc: Thomas Gleixner 
Cc: Krzysztof Kozlowski 
Signed-off-by: Will Deacon 
Acked-by: Krzysztof Kozlowski 
Reviewed-by: Chanwoo Choi 
Signed-off-by: Daniel Lezcano 
Link: https://lore.kernel.org/r/20210608154341.10794-3-will@kernel.org

clocksource/drivers/exynos_mct: Prioritise Arm arch timer on arm64

2021-08-13T07:24:22+00:00

All arm64 CPUs feature an architected timer, which offers a relatively
low-latency interface to a per-cpu clocksource and timer. For the most
part, using this interface is a no-brainer, with the exception of SoCs
where it cannot be used to wake up from deep idle state (i.e.
CLOCK_EVT_FEAT_C3STOP is set).

On the contrary, the Exynos MCT is extremely slow to access yet can be
used as a wakeup source. In preparation for using the Exynos MCT as a
potential wakeup timer for the Arm architected timer, reduce its ratings
so that the architected timer is preferred.

This effectively reverts the decision made in 6282edb72bed
("clocksource/drivers/exynos_mct: Increase priority over ARM arch timer")
for arm64, as the reasoning for the original change was to work around
a 32-bit SoC design.

Cc: Marek Szyprowski 
Cc: Krzysztof Kozlowski 
Cc: Chanwoo Choi 
Cc: Thomas Gleixner 
Signed-off-by: Will Deacon 
Tested-by: Krzysztof Kozlowski  # exynos-5422
Signed-off-by: Daniel Lezcano 
Link: https://lore.kernel.org/r/20210608154341.10794-2-will@kernel.org

clocksource: Replace setup_irq() by request_irq()

2020-02-27T11:15:24+00:00

request_irq() is preferred over setup_irq(). The early boot setup_irq()
invocations happen either via 'init_IRQ()' or 'time_init()', while
memory allocators are ready by 'mm_init()'.

Per tglx[1], setup_irq() existed in olden days when allocators were not
ready by the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

Seldom remove_irq() usage has been observed coupled with setup_irq(),
wherever that has been found, it too has been replaced by free_irq().

A build error that was reported by kbuild test robot 
in the previous version of the patch also has been fixed.

[1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos

Signed-off-by: afzal mohammed 
Signed-off-by: Daniel Lezcano 
Link: https://lore.kernel.org/r/91961c77c1cf93d41523f5e1ac52043f32f97077.1582799709.git.afzal.mohd.ma@gmail.com

clocksource/drivers/exynos_mct: Rename Exynos to lowercase

2020-01-16T18:09:02+00:00

Fix up inconsistent usage of upper and lowercase letters in "Exynos"
name.

"EXYNOS" is not an abbreviation but a regular trademarked name.
Therefore it should be written with lowercase letters starting with
capital letter.

The lowercase "Exynos" name is promoted by its manufacturer Samsung
Electronics Co., Ltd., in advertisement materials and on website.

Signed-off-by: Krzysztof Kozlowski 
Signed-off-by: Daniel Lezcano 
Link: https://lore.kernel.org/r/20200104152107.11407-12-krzk@kernel.org