Commit Graph

267 Commits

Author SHA1 Message Date
Krzysztof Kozlowski
8602a80bb8 clocksource/drivers/exynosy: Depend on sub-architecture for Exynos MCT and Samsung PWM
The Exynos MCT and Samsung PWM Timer clocksource drivers are not usable
on anything else than Samsung Exynos, S3C or S5P SoC platforms.  These
are integral parts of a SoC.  Even though the drivers are not user
selectable, still document the hardware architecture explicitly with
depends on ARCH_EXYNOS and others.  This also serves a purpose of
documenting use-case, if someone ever wonders whether to select the
driver for his platform.  No functional change, because drivers are
already selected by the platform described in depends. We follow similar
approach also for other SoC-specific drivers.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20211021063500.39314-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2021-10-21 12:54:28 +02:00
Linus Torvalds
514798d365 This round has a diffstat dominated by Qualcomm clk drivers. Honestly though
that's just a bunch of data so the diffstat reflects that. Looking beyond that
 there's just a bunch of updates all around in various clk drivers. Renesas and
 NXP (for i.MX) are two SoC vendors that have a lot of patches in here. Overall
 the driver changes look to be mostly enabling more clks and non-critical fixes
 that we could hold until the next merge window.
 
 I'm especially excited about the series from Arnd that graduates clkdev to be
 the only implementation of clk_get() and clk_put(). That's a good step in the
 right direction to migreate eveerything over to the common clk framework. Now
 we don't have to worry about clkdev specific details, they're just part of the
 clk API now.
 
 Core:
  - clkdev is now the only option, i.e. clk_get()/clk_put() is implemented in
    only one place in the kernel instead of in drivers/clk/clkdev.c and in
    architectures that want their own implementation
 
 New Drivers:
  - Texas Instruments' LMK04832 Ultra Low-Noise JESD204B Compliant Clock
    Jitter Cleaner With Dual Loop PLLs
  - Qualcomm MDM9607 GCC
  - Qualcomm SC8180X display clks
  - Qualcomm SM6125 GCC
  - Qualcomm SM8250 CAMCC (camera)
  - Renesas RZ/G2L SoC
  - Hisilicon hi3559A SoC
 
 Updates:
  - Stop using clock-output-names in ST clk drivers (yay!)
  - Support secure mode of STM32MP1 SoCs
  - Improve clock support for Actions S500 SoC
  - duty cycle setting support on qcom clks
  - Add TI am33xx spread spectrum clock support
  - Use determine_rate() for the Amlogic pll ops instead of round_rate()
  - Restrict Amlogic gp0/1 and audio plls range on g12a/sm1
  - Improve Amlogic axg-audio controller error on deferral
  - Add NNA clocks on Amlogic g12a
  - Reduce memory footprint of Rockchip PLL rate tables
  - A fix for the newly added Rockchip rk3568 clk driver
  - Exported clock for the newly added Rockchip video decoder
  - Remove audio ipg clock from i.MX8MP
  - Remove deprecated legacy clock binding for i.MX SCU clock driver
  - Use common clk-imx8qxp for both i.MX8QXP and i.MX8QM
  - Add multiple clocks to clk-imx8qxp driver (enet, hdmi, lcdif, audio,
    parallel interface)
  - Add dedicated clock ops for i.MX paralel interface
  - Different fixes for clocks controlled by ATF on i.MX SoCs
  - Add A53/A72 frequency scaling support i.MX clk-scu driver
  - Add special case for DCSS clock on suspend for i.MX clk-scu driver
  - Add parent save/restore on suspend/resume to i.MX clk-scu driver
  - Skip runtime PM enablement for CPU clocks in i.MX clk-scu driver
  - Remove the sys1_pll/sys2_pll clock gates for i.MX8MQ and their
    bindings
  - Tegra clk driver no longer deasserts resets on clk_enable as it
    gets in the way of certain power-up sequences
  - Fix compile testing for Tegra clk driver
  - One patch to fix a divider on the Allwinner v3s Audio PLL
  - Add support for CPU core clock boost modes on Renesas R-Car Gen3
  - Add ISPCS (Image Signal Processor) clocks on Renesas R-Car V3U
  - Switch SH/R-Mobile and R-Car "DIV6" clocks to .determine_rate()
    and improve support for multiple parents
  - Switch Renesas RZ/N1 divider clocks to .determine_rate()
  - Add ZA2 (Audio Clock Generator) clock on Renesas R-Car D3
  - Convert ar7 to common clk framework
  - Convert ralink to common clk framework
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Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux

Pull clk updates from Stephen Boyd:
 "This round has a diffstat dominated by Qualcomm clk drivers. Honestly
  though that's just a bunch of data so the diffstat reflects that.
  Looking beyond that there's just a bunch of updates all around in
  various clk drivers. Renesas and NXP (for i.MX) are two SoC vendors
  that have a lot of patches in here.

  Overall the driver changes look to be mostly enabling more clks and
  non-critical fixes that we could hold until the next merge window.

  I'm especially excited about the series from Arnd that graduates
  clkdev to be the only implementation of clk_get() and clk_put().
  That's a good step in the right direction to migreate eveerything over
  to the common clk framework. Now we don't have to worry about clkdev
  specific details, they're just part of the clk API now.

  Core:
   - clkdev is now the only option, i.e. clk_get()/clk_put() is
     implemented in only one place in the kernel instead of in
     drivers/clk/clkdev.c and in architectures that want their own
     implementation

  New Drivers:
   - Texas Instruments' LMK04832 Ultra Low-Noise JESD204B Compliant
     Clock Jitter Cleaner With Dual Loop PLLs
   - Qualcomm MDM9607 GCC
   - Qualcomm SC8180X display clks
   - Qualcomm SM6125 GCC
   - Qualcomm SM8250 CAMCC (camera)
   - Renesas RZ/G2L SoC
   - Hisilicon hi3559A SoC

  Updates:
   - Stop using clock-output-names in ST clk drivers (yay!)
   - Support secure mode of STM32MP1 SoCs
   - Improve clock support for Actions S500 SoC
   - duty cycle setting support on qcom clks
   - Add TI am33xx spread spectrum clock support
   - Use determine_rate() for the Amlogic pll ops instead of
     round_rate()
   - Restrict Amlogic gp0/1 and audio plls range on g12a/sm1
   - Improve Amlogic axg-audio controller error on deferral
   - Add NNA clocks on Amlogic g12a
   - Reduce memory footprint of Rockchip PLL rate tables
   - A fix for the newly added Rockchip rk3568 clk driver
   - Exported clock for the newly added Rockchip video decoder
   - Remove audio ipg clock from i.MX8MP
   - Remove deprecated legacy clock binding for i.MX SCU clock driver
   - Use common clk-imx8qxp for both i.MX8QXP and i.MX8QM
   - Add multiple clocks to clk-imx8qxp driver (enet, hdmi, lcdif,
     audio, parallel interface)
   - Add dedicated clock ops for i.MX paralel interface
   - Different fixes for clocks controlled by ATF on i.MX SoCs
   - Add A53/A72 frequency scaling support i.MX clk-scu driver
   - Add special case for DCSS clock on suspend for i.MX clk-scu driver
   - Add parent save/restore on suspend/resume to i.MX clk-scu driver
   - Skip runtime PM enablement for CPU clocks in i.MX clk-scu driver
   - Remove the sys1_pll/sys2_pll clock gates for i.MX8MQ and their
     bindings
   - Tegra clk driver no longer deasserts resets on clk_enable as it
     gets in the way of certain power-up sequences
   - Fix compile testing for Tegra clk driver
   - One patch to fix a divider on the Allwinner v3s Audio PLL
   - Add support for CPU core clock boost modes on Renesas R-Car Gen3
   - Add ISPCS (Image Signal Processor) clocks on Renesas R-Car V3U
   - Switch SH/R-Mobile and R-Car "DIV6" clocks to .determine_rate() and
     improve support for multiple parents
   - Switch Renesas RZ/N1 divider clocks to .determine_rate()
   - Add ZA2 (Audio Clock Generator) clock on Renesas R-Car D3
   - Convert ar7 to common clk framework
   - Convert ralink to common clk framework"

* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (161 commits)
  clk: zynqmp: Handle divider specific read only flag
  clk: zynqmp: Use firmware specific mux clock flags
  clk: zynqmp: Use firmware specific divider clock flags
  clk: zynqmp: Use firmware specific common clock flags
  clk: lmk04832: Use of match table
  clk: lmk04832: Depend on SPI
  clk: stm32mp1: new compatible for secure RCC support
  dt-bindings: clock: stm32mp1 new compatible for secure rcc
  dt-bindings: reset: add MCU HOLD BOOT ID for SCMI reset domains on stm32mp15
  dt-bindings: reset: add IDs for SCMI reset domains on stm32mp15
  dt-bindings: clock: add IDs for SCMI clocks on stm32mp15
  reset: stm32mp1: remove stm32mp1 reset
  clk: hisilicon: Add clock driver for hi3559A SoC
  dt-bindings: Document the hi3559a clock bindings
  clk: si5341: Add sysfs properties to allow checking/resetting device faults
  clk: si5341: Add silabs,iovdd-33 property
  clk: si5341: Add silabs,xaxb-ext-clk property
  clk: si5341: Allow different output VDD_SEL values
  clk: si5341: Update initialization magic
  clk: si5341: Check for input clock presence and PLL lock on startup
  ...
2021-07-01 13:26:16 -07:00
Andrea Merello
68e2215e9d arm: zynq: don't disable CONFIG_ARM_GLOBAL_TIMER due to CONFIG_CPU_FREQ anymore
Now ARM global timer driver could work even if it's source clock rate
changes, so we don't need to disable that driver when cpu frequency scaling
is in use.

This cause Zynq arch to get support for timer delay and get_cycles().

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Sören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210406130045.15491-3-andrea.merello@gmail.com
2021-06-16 17:33:04 +02:00
Andrea Merello
171b45a4a7 clocksource/drivers/arm_global_timer: Implement rate compensation whenever source clock changes
This patch adds rate change notification support for the parent clock;
should that clock change, then we try to adjust the our prescaler in order
to compensate (i.e. we adjust to still get the same timer frequency).

This is loosely based on what it's done in timer-cadence-ttc. timer-sun51,
mips-gic-timer and smp_twd.c also seem to look at their parent clock rate
and to perform some kind of adjustment whenever needed.

In this particular case we have only one single counter and prescaler for
all clocksource, clockevent and timer_delay, and we just update it for all
(i.e. we don't let it go and call clockevents_update_freq() to notify to
the kernel that our rate has changed).

Note that, there is apparently no other way to fixup things, because once
we call register_current_timer_delay(), specifying the timer rate, it seems
that that rate is not supposed to change ever.

In order for this mechanism to work, we have to make assumptions about how
much the initial clock is supposed to eventually decrease from the initial
one, and set our initial prescaler to a value that we can eventually
decrease enough to compensate. We provide an option in KConfig for this.

In case we end up in a situation in which we are not able to compensate the
parent clock change, we fail returning NOTIFY_BAD.

This fixes a real-world problem with Zynq arch not being able to use this
driver and CPU_FREQ at the same time (because ARM global timer is fed by
the CPU clock, which may keep changing when CPU_FREQ is enabled).

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Sören Brinkmann <soren.brinkmann@xilinx.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210406130045.15491-2-andrea.merello@gmail.com
2021-06-16 17:33:04 +02:00
Arnd Bergmann
2f4574dd6d clkdev: remove CONFIG_CLKDEV_LOOKUP
This option is now synonymous with CONFIG_HAVE_CLK, so use
the latter globally. Any out-of-tree platform ports that
still use a private clk_get()/clk_put() implementation should
move to CONFIG_COMMON_CLK.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2021-06-08 17:00:09 +02:00
Linus Torvalds
4aa364443d A small set of clockevent fixes which fell through the cracks
before the 5.11 release:
 
    - Ensure a clock is enabled on sh_cmt
    - Trivial compile fail and compile warning fixes
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Merge tag 'timers-urgent-2021-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer fixes from Thomas Gleixner:
 "A small set of clockevent fixes which fell through the cracks before
  the 5.11 release:

   - Ensure a clock is enabled on sh_cmt

   - Trivial compile fail and compile warning fixes"

* tag 'timers-urgent-2021-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/drivers/mxs_timer: Add missing semicolon when DEBUG is defined
  clocksource/drivers/sh_cmt: Make sure channel clock supply is enabled
  clocksource/drivers/ixp4xx: Select TIMER_OF when needed
2021-02-22 14:11:36 -08:00
Thomas Gleixner
11db5710d4 - Drop dead code on efm32 (Uwe Kleine-König)
- Move pr_fmt() before the includes on davinci driver (Bartosz
   Golaszewski)
 
 - Clarified timer interrupt must be specified on nuvoton DT bindings
   (Jonathan Neuschäfer)
 
 - Remove tango, sirf, u300 and atlas timer drivers (Arnd Bergman)
 
 - Add suspend/resume on pit64b (Claudiu Beznea)
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Merge tag 'timers-v5.12-rc1' of https://git.linaro.org/people/daniel.lezcano/linux into timers/core

Pull clocksource/events updates from Daniel Lezcano:

 - Drop dead code on efm32 (Uwe Kleine-König)

 - Move pr_fmt() before the includes on davinci driver (Bartosz
   Golaszewski)

 - Clarified timer interrupt must be specified on nuvoton DT bindings
   (Jonathan Neuschäfer)

 - Remove tango, sirf, u300 and atlas timer drivers (Arnd Bergman)

 - Add suspend/resume on pit64b (Claudiu Beznea)

Link: https://lore.kernel.org/r/3747fbde-134f-5e1d-47d5-8776c1a52aa1@linaro.org
2021-02-10 11:02:20 +01:00
Arnd Bergmann
a8d8023580 clocksource/drivers/prima: Remove sirf prima driver
The CSR SiRF prima2/atlas platforms are getting removed, so this driver
is no longer needed.

Cc: Barry Song <baohua@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Barry Song <baohua@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210120131559.1971359-5-arnd@kernel.org
2021-02-03 09:13:46 +01:00
Arnd Bergmann
446262b272 clocksource/drivers/atlas: Remove sirf atlas driver
The CSR SiRF prima2/atlas platforms are getting removed, so this driver
is no longer needed.

Cc: Barry Song <baohua@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Barry Song <baohua@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210120131559.1971359-4-arnd@kernel.org
2021-02-03 09:12:28 +01:00
Arnd Bergmann
8fdb441769 clocksource/drivers/tango: Remove tango driver
The tango platform is getting removed, so the driver is no
longer needed.

Cc: Marc Gonzalez <marc.w.gonzalez@free.fr>
Cc: Mans Rullgard <mans@mansr.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mans Rullgard <mans@mansr.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210120131559.1971359-3-arnd@kernel.org
2021-02-03 09:11:35 +01:00
Arnd Bergmann
3310540676 clocksource/drivers/u300: Remove the u300 driver
The ST-Ericsson U300 platform is getting removed, so this driver is no
longer needed.

Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210120131559.1971359-2-arnd@kernel.org
2021-02-03 09:10:24 +01:00
Uwe Kleine-König
523d83ef09 clocksource/drivers/efm32: Drop unused timer code
Support for this machine was just removed, so drop the now unused timer
code, too.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210115155130.185010-4-u.kleine-koenig@pengutronix.de
2021-01-18 16:29:54 +01:00
Arnd Bergmann
7a3b8758bd clocksource/drivers/ixp4xx: Select TIMER_OF when needed
Compile-testing the ixp4xx timer with CONFIG_OF enabled but
CONFIG_TIMER_OF disabled leads to a harmless warning:

arm-linux-gnueabi-ld: warning: orphan section `__timer_of_table' from `drivers/clocksource/timer-ixp4xx.o' being placed in section `__timer_of_table'

Move the select statement from the platform code into the driver
so it always gets enabled in configurations that rely on it.

Fixes: 40df14cc5c ("clocksource/drivers/ixp4xx: Add OF initialization support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210103135955.3808976-1-arnd@kernel.org
2021-01-18 16:20:15 +01:00
Linus Torvalds
7a932e5702 asm-generic: cross-architecture timer cleanup
This cleans up two ancient timer features that were never completed in
 the past, CONFIG_GENERIC_CLOCKEVENTS and CONFIG_ARCH_USES_GETTIMEOFFSET.
 
 There was only one user left for the ARCH_USES_GETTIMEOFFSET variant
 of clocksource implementations, the ARM EBSA110 platform. Rather than
 changing to use modern timekeeping, we remove the platform entirely as
 Russell no longer uses his machine and nobody else seems to have one
 any more.
 
 The conditional code for using arch_gettimeoffset() is removed as
 a result.
 
 For CONFIG_GENERIC_CLOCKEVENTS, there are still a couple of platforms
 not using clockevent drivers: parisc, ia64, most of m68k, and one
 Arm platform. These all do timer ticks slighly differently, and this
 gets cleaned up to the point they at least all call the same helper
 function. Instead of most platforms using 'select GENERIC_CLOCKEVENTS'
 in Kconfig, the polarity is now reversed, with the few remaining ones
 selecting LEGACY_TIMER_TICK instead.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'asm-generic-timers-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic cross-architecture timer cleanup from Arnd Bergmann:
 "This cleans up two ancient timer features that were never completed in
  the past, CONFIG_GENERIC_CLOCKEVENTS and CONFIG_ARCH_USES_GETTIMEOFFSET.

  There was only one user left for the ARCH_USES_GETTIMEOFFSET variant
  of clocksource implementations, the ARM EBSA110 platform. Rather than
  changing to use modern timekeeping, we remove the platform entirely as
  Russell no longer uses his machine and nobody else seems to have one
  any more.

  The conditional code for using arch_gettimeoffset() is removed as a
  result.

  For CONFIG_GENERIC_CLOCKEVENTS, there are still a couple of platforms
  not using clockevent drivers: parisc, ia64, most of m68k, and one Arm
  platform. These all do timer ticks slighly differently, and this gets
  cleaned up to the point they at least all call the same helper
  function.

  Instead of most platforms using 'select GENERIC_CLOCKEVENTS' in
  Kconfig, the polarity is now reversed, with the few remaining ones
  selecting LEGACY_TIMER_TICK instead"

* tag 'asm-generic-timers-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  timekeeping: default GENERIC_CLOCKEVENTS to enabled
  timekeeping: remove xtime_update
  m68k: remove timer_interrupt() function
  m68k: change remaining timers to legacy_timer_tick
  m68k: m68328: use legacy_timer_tick()
  m68k: sun3/sun3c: use legacy_timer_tick
  m68k: split heartbeat out of timer function
  m68k: coldfire: use legacy_timer_tick()
  parisc: use legacy_timer_tick
  ARM: rpc: use legacy_timer_tick
  ia64: convert to legacy_timer_tick
  timekeeping: add CONFIG_LEGACY_TIMER_TICK
  timekeeping: remove arch_gettimeoffset
  net: remove am79c961a driver
  ARM: remove ebsa110 platform
2020-12-16 00:07:17 -08:00
Kefeng Wang
ab3105446f clocksource/drivers/riscv: Make RISCV_TIMER depends on RISCV_SBI
The riscv timer is set via SBI timer call, let's make RISCV_TIMER
depends on RISCV_SBI, and it also fixes some build issue.

Fixes: d5be89a8d1 ("RISC-V: Resurrect the MMIO timer implementation for M-mode systems")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20201028131230.72907-1-wangkefeng.wang@huawei.com
2020-12-03 19:16:26 +01:00
Vineet Gupta
b6ea209ef1 clocksource/drivers/nps: Remove EZChip NPS clocksource driver
NPS platform has been removed from ARC port and there are no in-tree
users of it now. So RIP !

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20201105212210.1891598-2-vgupta@synopsys.com
2020-12-03 19:16:18 +01:00
Arnd Bergmann
77f6c0b874 timekeeping: remove arch_gettimeoffset
With Arm EBSA110 gone, nothing uses it any more, so the corresponding
code and the Kconfig option can be removed.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2020-10-30 21:57:04 +01:00
Anup Patel
2bc3fc877a
RISC-V: Remove CLINT related code from timer and arch
Right now the RISC-V timer driver is convoluted to support:
1. Linux RISC-V S-mode (with MMU) where it will use TIME CSR for
   clocksource and SBI timer calls for clockevent device.
2. Linux RISC-V M-mode (without MMU) where it will use CLINT MMIO
   counter register for clocksource and CLINT MMIO compare register
   for clockevent device.

We now have a separate CLINT timer driver which also provide CLINT
based IPI operations so let's remove CLINT MMIO related code from
arch/riscv directory and RISC-V timer driver.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Emil Renner Berhing <kernel@esmil.dk>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-08-20 10:58:13 -07:00
Anup Patel
2ac6795fcc
clocksource/drivers: Add CLINT timer driver
We add a separate CLINT timer driver for Linux RISC-V M-mode (i.e.
RISC-V NoMMU kernel).

The CLINT MMIO device provides three things:
1. 64bit free running counter register
2. 64bit per-CPU time compare registers
3. 32bit per-CPU inter-processor interrupt registers

Unlike other timer devices, CLINT provides IPI registers along with
timer registers. To use CLINT IPI registers, the CLINT timer driver
provides IPI related callbacks to arch/riscv.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Emil Renner Berhing <kernel@esmil.dk>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-08-20 10:57:29 -07:00
Linus Torvalds
884e0d3dd5 - Core Frameworks
- Make better attempt at matching device with the correct OF node
    - Allow batch removal of hierarchical sub-devices
 
  - New Drivers
    - Add STM32 Clocksource driver
    - Add support for Khadas System Control Microcontroller
 
  - Driver Removal
    - Remove unused driver for TI's SMSC ECE1099
 
  - New Device Support
    - Add support for Intel Emmitsburg PCH to Intel LPSS PCI
    - Add support for Intel Tiger Lake PCH-H to Intel LPSS PCI
    - Add support for Dialog DA revision to Dialog DA9063
 
  - New Functionality
    - Add support for AXP803 to be probed by I2C
 
  - Fix-ups
    - Numerous W=1 warning fixes
    - Device Tree changes; stm32-lptimer, gateworks-gsc, khadas,mcu, stmfx, cros-ec, j721e-system-controller
    - Enabled Regmap 'fast I/O'; stm32-lptimer
    - Change BUG_ON to WARN_ON; arizona-core
    - Remove superfluous code/initialisation; madera, max14577
    - Trivial formatting/spelling issues; madera-core, madera-i2c, da9055, max77693-private
    - Switch to of_platform_populate(); sprd-sc27xx-spi
    - Expand out set/get brightness/pwm macros; lm3533-ctrlbank
    - Disable IRQs on suspend; motorola-cpcap
    - Clean-up error handling; intel_soc_pmic_mrfld
    - Ensure correct removal order of sub-devices; madera
    - Many s/HTTP/HTTPS/ link changes
    - Ensure name used with Regmap is unique; syscon
 
  - Bug Fixes
    - Properly 'put' clock on unbind and error; arizona-core
    - Fix revision handling; da9063
    - Fix 'assignment of read-only location' error; kempld-core
    - Avoid using the Regmap API when atomic; rn5t618
    - Redefine volatile register description; rn5t618
    - Use locking to protect event handler; dln2
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Merge tag 'mfd-next-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd

Pull MFD updates from Lee Jones:
 "Core Frameworks
   - Make better attempt at matching device with the correct OF node
   - Allow batch removal of hierarchical sub-devices

  New Drivers
   - Add STM32 Clocksource driver
   - Add support for Khadas System Control Microcontroller

  Driver Removal
   - Remove unused driver for TI's SMSC ECE1099

  New Device Support
   - Add support for Intel Emmitsburg PCH to Intel LPSS PCI
   - Add support for Intel Tiger Lake PCH-H to Intel LPSS PCI
   - Add support for Dialog DA revision to Dialog DA9063

  New Functionality
   - Add support for AXP803 to be probed by I2C

  Fix-ups
   - Numerous W=1 warning fixes
   - Device Tree changes (stm32-lptimer, gateworks-gsc, khadas,mcu, stmfx, cros-ec, j721e-system-controller)
   - Enabled Regmap 'fast I/O' in stm32-lptimer
   - Change BUG_ON to WARN_ON in arizona-core
   - Remove superfluous code/initialisation (madera, max14577)
   - Trivial formatting/spelling issues (madera-core, madera-i2c, da9055, max77693-private)
   - Switch to of_platform_populate() in sprd-sc27xx-spi
   - Expand out set/get brightness/pwm macros in lm3533-ctrlbank
   - Disable IRQs on suspend in motorola-cpcap
   - Clean-up error handling in intel_soc_pmic_mrfld
   - Ensure correct removal order of sub-devices in madera
   - Many s/HTTP/HTTPS/ link changes
   - Ensure name used with Regmap is unique in syscon

  Bug Fixes
   - Properly 'put' clock on unbind and error in arizona-core
   - Fix revision handling in da9063
   - Fix 'assignment of read-only location' error in kempld-core
   - Avoid using the Regmap API when atomic in rn5t618
   - Redefine volatile register description in rn5t618
   - Use locking to protect event handler in dln2"

* tag 'mfd-next-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd: (76 commits)
  mfd: syscon: Use a unique name with regmap_config
  mfd: Replace HTTP links with HTTPS ones
  mfd: dln2: Run event handler loop under spinlock
  mfd: madera: Improve handling of regulator unbinding
  mfd: mfd-core: Add mechanism for removal of a subset of children
  mfd: intel_soc_pmic_mrfld: Simplify the return expression of intel_scu_ipc_dev_iowrite8()
  mfd: max14577: Remove redundant initialization of variable current_bits
  mfd: rn5t618: Fix caching of battery related registers
  mfd: max77693-private: Drop a duplicated word
  mfd: da9055: pdata.h: Drop a duplicated word
  mfd: rn5t618: Make restart handler atomic safe
  mfd: kempld-core: Fix 'assignment of read-only location' error
  mfd: axp20x: Allow the AXP803 to be probed by I2C
  mfd: da9063: Add support for latest DA silicon revision
  mfd: da9063: Fix revision handling to correctly select reg tables
  dt-bindings: mfd: st,stmfx: Remove I2C unit name
  dt-bindings: mfd: ti,j721e-system-controller.yaml: Add J721e system controller
  mfd: motorola-cpcap: Disable interrupt for suspend
  mfd: smsc-ece1099: Remove driver
  mfd: core: Add OF_MFD_CELL_REG() helper
  ...
2020-08-15 08:09:38 -07:00
周琰杰 (Zhou Yanjie)
5ecafc120b clocksource/drivers/ingenic: Add support for the Ingenic X1000 OST.
X1000 and SoCs after X1000 (such as X1500 and X1830) had a separate
OST, it no longer belongs to TCU. This driver will register both a
clocksource and a sched_clock to the system.

Tested-by: 周正 (Zhou Zheng) <sernia.zhou@foxmail.com>
Co-developed-by: 漆鹏振 (Qi Pengzhen) <aric.pzqi@ingenic.com>
Signed-off-by: 漆鹏振 (Qi Pengzhen) <aric.pzqi@ingenic.com>
Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
Reviewed-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200722171804.97559-3-zhouyanjie@wanyeetech.com
2020-07-23 16:58:09 +02:00
Anson Huang
a6d0812a08 clocksource/drivers/imx: Add support for i.MX TPM driver with ARM64
Allows building and compile-testing the i.MX TPM driver for ARM64.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1594178168-13007-1-git-send-email-Anson.Huang@nxp.com
2020-07-23 16:57:34 +02:00
Benjamin Gaignard
48b41c5e2d clocksource: Add Low Power STM32 timers driver
Implement clock event driver using low power STM32 timers.
Low power timer counters running even when CPUs are stopped.
It could be used as clock event broadcaster to wake up CPUs but not like
a clocksource because each it rise an interrupt the counter restart from 0.

Low power timers have a 16 bits counter and a prescaler which allow to
divide the clock per power of 2 to up 128 to target a 32KHz rate.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Pascal Paillet <p.paillet@st.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2020-06-18 11:19:58 +01:00
Serge Semin
7d7de1a653 clocksource: mips-gic-timer: Mark GIC timer as unstable if ref clock changes
Currently clocksource framework doesn't support the clocks with variable
frequency. Since MIPS GIC timer ticks rate might be unstable on some
platforms, we must make sure that it justifies the clocksource
requirements. MIPS GIC timer is incremented with the CPU cluster reference
clocks rate. So in case if CPU frequency changes, the MIPS GIC tick rate
changes synchronously. Due to this the clocksource subsystem can't rely on
the timer to measure system clocks anymore. This commit marks the MIPS GIC
based clocksource as unstable if reference clock (normally it's a CPU
reference clocks) rate changes. The clocksource will execute a watchdog
thread, which lowers the MIPS GIC timer rating to zero and fallbacks to a
new stable one.

Note we don't need to set the CLOCK_SOURCE_MUST_VERIFY flag to the MIPS
GIC clocksource since normally the timer is stable. The only reason why
it gets unstable is due to the ref clock rate change, which event we
detect here in the driver by means of the clocks event notifier.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-rtc@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200521204818.25436-9-Sergey.Semin@baikalelectronics.ru
2020-05-23 00:03:16 +02:00
Johan Hovold
83cba95369 clocksource/drivers/rda: drop redundant Kconfig dependency
Since commit 2f8a26c166 ("clocksource: Improve GENERIC_CLOCKEVENTS
dependency") all clocksource drivers depend on GENERIC_CLOCKEVENTS so
drop the redundant attribute from the RDA-timer entry which was added
later.

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200513122548.16974-1-johan@kernel.org
2020-05-22 23:58:56 +02:00
Rob Herring
bfed0eded1 clocksource/drivers/versatile: Allow CONFIG_CLKSRC_VERSATILE to be disabled
The timer-versatile driver provides a sched_clock for certain Arm Ltd.
reference platforms. Specifically, it is used on Versatile and 32-bit
VExpress. It is not needed for those platforms with an arch timer (all
the 64-bit ones) yet CONFIG_MFD_VEXPRESS_SYSREG does still need to be
enabled. In that case, the timer-versatile can only be disabled when
COMPILE_TEST is enabled which is not desirable. Let's use the sub-arch
kconfig symbols instead.

Realview platforms don't have the sysregs that this driver uses so
correct the help text.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200417212045.16917-1-robh@kernel.org
2020-04-27 11:33:44 +02:00
Michael Ellerman
25259f7a5d clocksource/drivers/timer-microchip-pit64b: Select CONFIG_TIMER_OF
This driver is an OF driver, it depends on OF, and uses
TIMER_OF_DECLARE, so it should select CONFIG_TIMER_OF.

Without CONFIG_TIMER_OF enabled this can lead to warnings such as:

  powerpc-linux-ld: warning: orphan section `__timer_of_table' from
  `drivers/clocksource/timer-microchip-pit64b.o' being placed in
  section `__timer_of_table'.

Because TIMER_OF_TABLES in vmlinux.lds.h doesn't emit anything into
the linker script when CONFIG_TIMER_OF is not enabled.

Fixes: 625022a5f1 ("clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support")
Cc: stable@vger.kernel.org # v5.6+
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200426124356.3929682-1-mpe@ellerman.id.au
2020-04-27 08:59:50 +02:00
Maarten ter Huurne
ca7b72b5a5 clocksource: Add driver for the Ingenic JZ47xx OST
OST is the OS Timer, a 64-bit timer/counter with buffered reading.

SoCs before the JZ4770 had (if any) a 32-bit OST; the JZ4770 and
JZ4780 have a 64-bit OST.

This driver will register both a clocksource and a sched_clock to the
system.

Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200212180408.30872-1-paul@crapouillou.net
2020-02-27 09:37:29 +01:00
Claudiu Beznea
625022a5f1 clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support
Add driver for Microchip PIT64B timer. Timer could be used in continuous
mode or oneshot mode. The hardware has 2x32 bit registers for period
emulating a 64 bit timer. The LSB_PR and MSB_PR registers are used to
set the period value (compare value). TLSB and TMSB keeps the current
value of the counter. After a compare the TLSB and TMSB register resets.
The driver uses PIT64B timer for clocksource or clockevent. First
requested timer would be registered as clockevent, second one would be
registered as clocksource. Individual PIT64B hardware resources were
used for clocksource and clockevent to be able to support high resolution
timers with this hardware implementation.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1576235962-30123-3-git-send-email-claudiu.beznea@microchip.com
2020-01-16 19:06:57 +01:00
Randy Dunlap
062934634d clocksource: Fix Kconfig miscues
Fix lots of typo, spelling, punctuation, and grammar miscues in
drivers/clocksource/Kconfig.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/4deb42a9-82f2-72f9-891f-972a9a399f4f@infradead.org
2020-01-16 19:06:57 +01:00
Krzysztof Kozlowski
9ca9fe69ee clocksource: Fix Kconfig indentation
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
	$ sed -e 's/^        /\t/' -i */Kconfig

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20191120134236.15959-1-krzk@kernel.org
2020-01-16 19:06:57 +01:00
Geert Uytterhoeven
227314239a clocksource/drivers/renesas-ostm: Convert to timer_of
Convert the Renesas OSTM driver to use the timer_of framework.
This reduces the driver object size by 367 bytes (with gcc 7.4.0).

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20191016144747.29538-4-geert+renesas@glider.be
2019-11-04 10:38:46 +01:00
Linus Torvalds
5c6bd5de3c Main MIPS changes for v5.4:
- boot_mem_map is removed, providing a nice cleanup made possible by the
   recent removal of bootmem.
 
 - Some fixes to atomics, in general providing compiler barriers for
   smp_mb__{before,after}_atomic plus fixes specific to Loongson CPUs or
   MIPS32 systems using cmpxchg64().
 
 - Conversion to the new generic VDSO infrastructure courtesy of Vincenzo
   Frascino.
 
 - Removal of undefined behavior in set_io_port_base(), fixing the
   behavior of some MIPS kernel configurations when built with recent
   clang versions.
 
 - Initial MIPS32 huge page support, functional on at least Ingenic SoCs.
 
 - pte_special() is now supported for some configurations, allowing among
   other things generic fast GUP to be used.
 
 - Miscellaneous fixes & cleanups.
 
 And platform specific changes:
 
 - Major improvements to Ingenic SoC support from Paul Cercueil, mostly
   enabled by the inclusion of the new TCU (timer-counter unit) drivers
   he's spent a very patient year or so working on. Plus some fixes for
   X1000 SoCs from Zhou Yanjie.
 
 - Netgear R6200 v1 systems are now supported by the bcm47xx platform.
 
 - DT updates for BMIPS, Lantiq & Microsemi Ocelot systems.
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Merge tag 'mips_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

Pull MIPS updates from Paul Burton:
 "Main MIPS changes:

   - boot_mem_map is removed, providing a nice cleanup made possible by
     the recent removal of bootmem.

   - Some fixes to atomics, in general providing compiler barriers for
     smp_mb__{before,after}_atomic plus fixes specific to Loongson CPUs
     or MIPS32 systems using cmpxchg64().

   - Conversion to the new generic VDSO infrastructure courtesy of
     Vincenzo Frascino.

   - Removal of undefined behavior in set_io_port_base(), fixing the
     behavior of some MIPS kernel configurations when built with recent
     clang versions.

   - Initial MIPS32 huge page support, functional on at least Ingenic
     SoCs.

   - pte_special() is now supported for some configurations, allowing
     among other things generic fast GUP to be used.

   - Miscellaneous fixes & cleanups.

  And platform specific changes:

   - Major improvements to Ingenic SoC support from Paul Cercueil,
     mostly enabled by the inclusion of the new TCU (timer-counter unit)
     drivers he's spent a very patient year or so working on. Plus some
     fixes for X1000 SoCs from Zhou Yanjie.

   - Netgear R6200 v1 systems are now supported by the bcm47xx platform.

   - DT updates for BMIPS, Lantiq & Microsemi Ocelot systems"

* tag 'mips_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (89 commits)
  MIPS: Detect bad _PFN_SHIFT values
  MIPS: Disable pte_special() for MIPS32 with RiXi
  MIPS: ralink: deactivate PCI support for SOC_MT7621
  mips: compat: vdso: Use legacy syscalls as fallback
  MIPS: Drop Loongson _CACHE_* definitions
  MIPS: tlbex: Remove cpu_has_local_ebase
  MIPS: tlbex: Simplify r3k check
  MIPS: Select R3k-style TLB in Kconfig
  MIPS: PCI: refactor ioc3 special handling
  mips: remove ioremap_cachable
  mips/atomic: Fix smp_mb__{before,after}_atomic()
  mips/atomic: Fix loongson_llsc_mb() wreckage
  mips/atomic: Fix cmpxchg64 barriers
  MIPS: Octeon: remove duplicated include from dma-octeon.c
  firmware: bcm47xx_nvram: Allow COMPILE_TEST
  firmware: bcm47xx_nvram: Correct size_t printf format
  MIPS: Treat Loongson Extensions as ASEs
  MIPS: Remove dev_err() usage after platform_get_irq()
  MIPS: dts: mscc: describe the PTP ready interrupt
  MIPS: dts: mscc: describe the PTP register range
  ...
2019-09-22 09:30:30 -07:00
Alexandre Belloni
1ce861cec0 clocksource/drivers/tcb_clksrc: Register delay timer
Implement and register delay timer to allow get_cycles() to work properly.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-08-27 00:31:39 +02:00
Paul Cercueil
34e9368301
clocksource: Add a new timer-ingenic driver
This driver handles the TCU (Timer Counter Unit) present on the Ingenic
JZ47xx SoCs, and provides the kernel with a system timer, a clocksource
and a sched_clock.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Mathieu Malaterre <malat@debian.org>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-mips@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Cc: od@zcrc.me
2019-08-08 15:30:08 -07:00
Bartosz Golaszewski
721154f972 clocksource/drivers/davinci: Add support for clockevents
Currently the clocksource and clockevent support for davinci platforms
lives in mach-davinci. It hard-codes many things, uses global variables,
implements functionalities unused by any platform and has code fragments
scattered across many (often unrelated) files.

Implement a new, modern and simplified timer driver and put it into
drivers/clocksource. We still need to support legacy board files so
export a config structure and a function that allows machine code to
register the timer.

The timer we're using is 64-bit but can be programmed in dual 32-bit
mode (both chained and unchained).

On all davinci SoCs except for da830 we're using both halves. Lower half
for clockevents and upper half for clocksource. On da830 we're using the
lower half for both with the help of a compare register.

This patch contains the core code and support for clockevent. The
clocksource code will be included in a subsequent patch.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-06-25 20:46:14 +02:00
Bai Ping
7117a44bc0 clocksource/drivers/sysctr: Add nxp system counter timer driver support
The system counter (sys_ctr) is a programmable system counter
which provides a shared time base to the Cortex A15, A7, A53 etc cores.
It is intended for use in applications where the counter is always
powered on and supports multiple, unrelated clocks. The sys_ctr hardware
supports:
 - 56-bit counter width (roll-over time greater than 40 years)
 - compare frame(64-bit compare value) contains programmable interrupt
   generation when compare value <= counter value.

[dlezcano] Fixed over 80 chars length warning

Signed-off-by: Bai Ping <ping.bai@nxp.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-06-25 19:49:18 +02:00
Dmitry Osipenko
acb4bb3f37 clocksource/drivers/tegra: Support COMPILE_TEST universally
Remove build dependency on ARM for compile-testing to allow non-arch
specific build-bots (like Intel's test robot) to compile the driver and
report about problems.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Acked-By: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-06-25 19:49:18 +02:00
Thomas Gleixner
ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Linus Torvalds
a13f950ef1 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull clocksource updates from Ingo Molnar:
 "Misc clocksource/clockevent driver updates that came in a bit late but
  are ready for v5.2"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  misc: atmel_tclib: Do not probe already used TCBs
  clocksource/drivers/timer-atmel-tcb: Convert tc_clksrc_suspend|resume() to static
  clocksource/drivers/tcb_clksrc: Rename the file for consistency
  clocksource/drivers/timer-atmel-pit: Rework Kconfig option
  clocksource/drivers/tcb_clksrc: Move Kconfig option
  ARM: at91: Implement clocksource selection
  clocksource/drivers/tcb_clksrc: Use tcb as sched_clock
  clocksource/drivers/tcb_clksrc: Stop depending on atmel_tclib
  ARM: at91: move SoC specific definitions to SoC folder
  clocksource/drivers/timer-milbeaut: Cleanup common register accesses
  clocksource/drivers/timer-milbeaut: Add shutdown function
  clocksource/drivers/timer-milbeaut: Fix to enable one-shot timer
  clocksource/drivers/tegra: Rework for compensation of suspend time
  clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804
  clocksource/drivers/sun4i: Add a compatible for suniv
  dt-bindings: timer: Add Allwinner suniv timer
2019-05-19 11:11:20 -07:00
Olof Johansson
7a0c4c1708 Merge branch 'fixes' into arm/soc
Merge in a few pending fixes from pre-5.1 that didn't get sent in:

MAINTAINERS: update arch/arm/mach-davinci
ARM: dts: ls1021: Fix SGMII PCS link remaining down after PHY disconnect
ARM: dts: imx6q-logicpd: Reduce inrush current on USBH1
ARM: dts: imx6q-logicpd: Reduce inrush current on start
ARM: dts: imx: Fix the AR803X phy-mode
ARM: dts: sun8i: a33: Reintroduce default pinctrl muxing
arm64: dts: allwinner: a64: Rename hpvcc-supply to cpvdd-supply
ARM: sunxi: fix a leaked reference by adding missing of_node_put
ARM: sunxi: fix a leaked reference by adding missing of_node_put

Signed-off-by: Olof Johansson <olof@lixom.net>
2019-05-15 22:51:48 -07:00
Alexandre Belloni
2f982703bd clocksource/drivers/timer-atmel-pit: Rework Kconfig option
Allow building the PIT driver when COMPILE_TEST is enabled. Also remove its
default value so it can be disabled.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-05-02 21:55:58 +02:00
Alexandre Belloni
6275f4947e clocksource/drivers/tcb_clksrc: Move Kconfig option
Move the ATMEL_TCB_CLKSRC option to drivers/clocksource and make it silent
if COMPILE_TEST is not selected.

Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-05-02 21:55:58 +02:00
David Abdurachmanov
dfc82faad7 clocksource/drivers/sp804: Add COMPILE_TEST to CONFIG_ARM_TIMER_SP804
This is only used on arm and arm64 platforms. Add COMPILE_TEST option.

Tested with 5.1-rc3+ on Fedora/RISCV. CONFIG_ARM_TIMER_SP804 no more shows
up in riscv config.

Signed-off-by: David Abdurachmanov <david.abdurachmanov@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-05-02 21:55:58 +02:00
Linus Walleij
13e0b4059b clocksource/drivers/ixp4xx: Add driver
This adds a new slightly rewritten timer driver for the
Intel IXP4xx clocksource, clockevent and delay timer.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-23 16:02:13 +02:00
Arnd Bergmann
99834eead2 clocksource/drivers/npcm: select TIMER_OF
When this is disabled, we get a link failure:

drivers/clocksource/timer-npcm7xx.o: In function `npcm7xx_timer_init':
timer-npcm7xx.c:(.init.text+0xf): undefined reference to `timer_of_init'

Fixes: 1c00289ecd ("clocksource/drivers/npcm: Add NPCM7xx timer driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-04-11 22:13:43 +02:00
Linus Torvalds
64b1b217f1 ARM: New SoC family support
Two new SoC families are added this time.
 
 Sugaya Taichi submitted support for the Milbeaut SoC family from
 Socionext and explains:
 
  "SC2000 is a SoC of the Milbeaut series. equipped with a DSP optimized for
   computer vision. It also features advanced functionalities such as 360-degree,
   real-time spherical stitching with multi cameras, image stabilization for
   without mechanical gimbals, and rolling shutter correction. More detail is
   below:
   https://www.socionext.com/en/products/assp/milbeaut/SC2000.html"
 
 Interestingly, this one has a history dating back to older chips
 made by Socionext and previously Matsushita/Panasonic based on their
 own mn10300 CPU architecture that was removed from the kernel last year.
 
 Manivannan Sadhasivam adds support for another SoC family, this is the
 Bitmain BM1880 chip used in the Sophon Edge TPU developer board.
 The chip is intended for Deep Learning applications, and comes
 with dual-core Arm Cortex-A53 to run Linux as well as a RISC-V
 microcontroller core to control the tensor unit.
 For the moment, the TPU is not accessible in mainline Linux, so
 we treat it as a generic Arm SoC.
 More information is available at https://www.sophon.ai/
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'armsoc-newsoc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARM new SoC family support from Arnd Bergmann:
 "Two new SoC families are added this time.

  Sugaya Taichi submitted support for the Milbeaut SoC family from
  Socionext and explains:

    "SC2000 is a SoC of the Milbeaut series. equipped with a DSP
     optimized for computer vision. It also features advanced
     functionalities such as 360-degree, real-time spherical stitching
     with multi cameras, image stabilization for without mechanical
     gimbals, and rolling shutter correction. More detail is below:

       https://www.socionext.com/en/products/assp/milbeaut/SC2000.html"

  Interestingly, this one has a history dating back to older chips made
  by Socionext and previously Matsushita/Panasonic based on their own
  mn10300 CPU architecture that was removed from the kernel last year.

  Manivannan Sadhasivam adds support for another SoC family, this is the
  Bitmain BM1880 chip used in the Sophon Edge TPU developer board.

  The chip is intended for Deep Learning applications, and comes with
  dual-core Arm Cortex-A53 to run Linux as well as a RISC-V
  microcontroller core to control the tensor unit. For the moment, the
  TPU is not accessible in mainline Linux, so we treat it as a generic
  Arm SoC.

  More information is available at

       https://www.sophon.ai/"

* tag 'armsoc-newsoc' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc:
  ARM: multi_v7_defconfig: add ARCH_MILBEAUT and ARCH_MILBEAUT_M10V
  ARM: configs: Add Milbeaut M10V defconfig
  ARM: dts: milbeaut: Add device tree set for the Milbeaut M10V board
  clocksource/drivers/timer-milbeaut: Introduce timer for Milbeaut SoCs
  dt-bindings: timer: Add Milbeaut M10V timer description
  ARM: milbeaut: Add basic support for Milbeaut m10v SoC
  dt-bindings: Add documentation for Milbeaut SoCs
  dt-bindings: arm: Add SMP enable-method for Milbeaut
  dt-bindings: sram: milbeaut: Add binding for Milbeaut smp-sram
  MAINTAINERS: Add entry for Bitmain SoC platform
  arm64: dts: bitmain: Add Sophon Egde board support
  arm64: dts: bitmain: Add BM1880 SoC support
  arm64: Add ARCH_BITMAIN platform
  dt-bindings: arm: Document Bitmain BM1880 SoC
2019-03-06 10:15:42 -08:00
Sugaya Taichi
b58f28f306 clocksource/drivers/timer-milbeaut: Introduce timer for Milbeaut SoCs
Add timer driver for Milbeaut SoCs series.

The timer has two 32-bit width down counters, one of which is configured
as a clockevent device and the other is configured as a clock source.

Signed-off-by: Sugaya Taichi <sugaya.taichi@socionext.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2019-03-01 15:18:27 +01:00
Joseph Lo
b4822dc756 clocksource/drivers/tegra: Add Tegra210 timer support
Add support for the Tegra210 timer that runs at oscillator clock
(TMR10-TMR13). We need these timers to work as clock event device and to
replace the ARMv8 architected timer due to it can't survive across the
power cycle of the CPU core or CPUPORESET signal. So it can't be a wake-up
source when CPU suspends in power down state.

Also convert the original driver to use timer-of API.

Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-02-23 12:13:45 +01:00
Samuel Holland
c950ca8c35 clocksource/drivers/arch_timer: Workaround for Allwinner A64 timer instability
The Allwinner A64 SoC is known[1] to have an unstable architectural
timer, which manifests itself most obviously in the time jumping forward
a multiple of 95 years[2][3]. This coincides with 2^56 cycles at a
timer frequency of 24 MHz, implying that the time went slightly backward
(and this was interpreted by the kernel as it jumping forward and
wrapping around past the epoch).

Investigation revealed instability in the low bits of CNTVCT at the
point a high bit rolls over. This leads to power-of-two cycle forward
and backward jumps. (Testing shows that forward jumps are about twice as
likely as backward jumps.) Since the counter value returns to normal
after an indeterminate read, each "jump" really consists of both a
forward and backward jump from the software perspective.

Unless the kernel is trapping CNTVCT reads, a userspace program is able
to read the register in a loop faster than it changes. A test program
running on all 4 CPU cores that reported jumps larger than 100 ms was
run for 13.6 hours and reported the following:

 Count | Event
-------+---------------------------
  9940 | jumped backward      699ms
   268 | jumped backward     1398ms
     1 | jumped backward     2097ms
 16020 | jumped forward       175ms
  6443 | jumped forward       699ms
  2976 | jumped forward      1398ms
     9 | jumped forward    356516ms
     9 | jumped forward    357215ms
     4 | jumped forward    714430ms
     1 | jumped forward   3578440ms

This works out to a jump larger than 100 ms about every 5.5 seconds on
each CPU core.

The largest jump (almost an hour!) was the following sequence of reads:
    0x0000007fffffffff → 0x00000093feffffff → 0x0000008000000000

Note that the middle bits don't necessarily all read as all zeroes or
all ones during the anomalous behavior; however the low 10 bits checked
by the function in this patch have never been observed with any other
value.

Also note that smaller jumps are much more common, with backward jumps
of 2048 (2^11) cycles observed over 400 times per second on each core.
(Of course, this is partially explained by lower bits rolling over more
frequently.) Any one of these could have caused the 95 year time skip.

Similar anomalies were observed while reading CNTPCT (after patching the
kernel to allow reads from userspace). However, the CNTPCT jumps are
much less frequent, and only small jumps were observed. The same program
as before (except now reading CNTPCT) observed after 72 hours:

 Count | Event
-------+---------------------------
    17 | jumped backward      699ms
    52 | jumped forward       175ms
  2831 | jumped forward       699ms
     5 | jumped forward      1398ms

Further investigation showed that the instability in CNTPCT/CNTVCT also
affected the respective timer's TVAL register. The following values were
observed immediately after writing CNVT_TVAL to 0x10000000:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL          | CNTV_TVAL Error
--------------------+------------+--------------------+-----------------
 0x000000d4a2d8bfff | 0x10003fff | 0x000000d4b2d8bfff | +0x00004000
 0x000000d4a2d94000 | 0x0fffffff | 0x000000d4b2d97fff | -0x00004000
 0x000000d4a2d97fff | 0x10003fff | 0x000000d4b2d97fff | +0x00004000
 0x000000d4a2d9c000 | 0x0fffffff | 0x000000d4b2d9ffff | -0x00004000

The pattern of errors in CNTV_TVAL seemed to depend on exactly which
value was written to it. For example, after writing 0x10101010:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL          | CNTV_TVAL Error
--------------------+------------+--------------------+-----------------
 0x000001ac3effffff | 0x1110100f | 0x000001ac4f10100f | +0x1000000
 0x000001ac40000000 | 0x1010100f | 0x000001ac5110100f | -0x1000000
 0x000001ac58ffffff | 0x1110100f | 0x000001ac6910100f | +0x1000000
 0x000001ac66000000 | 0x1010100f | 0x000001ac7710100f | -0x1000000
 0x000001ac6affffff | 0x1110100f | 0x000001ac7b10100f | +0x1000000
 0x000001ac6e000000 | 0x1010100f | 0x000001ac7f10100f | -0x1000000

I was also twice able to reproduce the issue covered by Allwinner's
workaround[4], that writing to TVAL sometimes fails, and both CVAL and
TVAL are left with entirely bogus values. One was the following values:

 CNTVCT             | CNTV_TVAL  | CNTV_CVAL
--------------------+------------+--------------------------------------
 0x000000d4a2d6014c | 0x8fbd5721 | 0x000000d132935fff (615s in the past)
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>

========================================================================

Because the CPU can read the CNTPCT/CNTVCT registers faster than they
change, performing two reads of the register and comparing the high bits
(like other workarounds) is not a workable solution. And because the
timer can jump both forward and backward, no pair of reads can
distinguish a good value from a bad one. The only way to guarantee a
good value from consecutive reads would be to read _three_ times, and
take the middle value only if the three values are 1) each unique and
2) increasing. This takes at minimum 3 counter cycles (125 ns), or more
if an anomaly is detected.

However, since there is a distinct pattern to the bad values, we can
optimize the common case (1022/1024 of the time) to a single read by
simply ignoring values that match the error pattern. This still takes no
more than 3 cycles in the worst case, and requires much less code. As an
additional safety check, we still limit the loop iteration to the number
of max-frequency (1.2 GHz) CPU cycles in three 24 MHz counter periods.

For the TVAL registers, the simple solution is to not use them. Instead,
read or write the CVAL and calculate the TVAL value in software.

Although the manufacturer is aware of at least part of the erratum[4],
there is no official name for it. For now, use the kernel-internal name
"UNKNOWN1".

[1]: https://github.com/armbian/build/commit/a08cd6fe7ae9
[2]: https://forum.armbian.com/topic/3458-a64-datetime-clock-issue/
[3]: https://irclog.whitequark.org/linux-sunxi/2018-01-26
[4]: https://github.com/Allwinner-Homlet/H6-BSP4.9-linux/blob/master/drivers/clocksource/arm_arch_timer.c#L272

Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Tested-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-02-23 12:13:45 +01:00