[PATCH v7 2/3] clocksource: Add JH7110 timer driver
Xingyu Wu
xingyu.wu at starfivetech.com
Wed Oct 25 02:04:42 PDT 2023
On 2023/10/24 22:56, Daniel Lezcano wrote:
>
> Hi Xingyu,
>
>
> On 19/10/2023 07:35, Xingyu Wu wrote:
>> Add timer driver for the StarFive JH7110 SoC.
>
> As it is a new timer, please add a proper nice description explaining the timer hardware, thanks.
OK. Will add the description in next version.
>
>> Signed-off-by: Xingyu Wu <xingyu.wu at starfivetech.com>
>> ---
>> MAINTAINERS | 7 +
>> drivers/clocksource/Kconfig | 11 +
>> drivers/clocksource/Makefile | 1 +
>> drivers/clocksource/timer-jh7110.c | 380 +++++++++++++++++++++++++++++
>> 4 files changed, 399 insertions(+)
>> create mode 100644 drivers/clocksource/timer-jh7110.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index 7a7bd8bd80e9..91c09b399131 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -20473,6 +20473,13 @@ S: Maintained
>> F: Documentation/devicetree/bindings/sound/starfive,jh7110-tdm.yaml
>> F: sound/soc/starfive/jh7110_tdm.c
>> +STARFIVE JH7110 TIMER DRIVER
>> +M: Samin Guo <samin.guo at starfivetech.com>
>> +M: Xingyu Wu <xingyu.wu at starfivetech.com>
>> +S: Supported
>> +F: Documentation/devicetree/bindings/timer/starfive,jh7110-timer.yaml
>> +F: drivers/clocksource/timer-jh7110.c
>> +
>> STARFIVE JH71X0 CLOCK DRIVERS
>> M: Emil Renner Berthing <kernel at esmil.dk>
>> M: Hal Feng <hal.feng at starfivetech.com>
>> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
>> index 0ba0dc4ecf06..821abcc1e517 100644
>> --- a/drivers/clocksource/Kconfig
>> +++ b/drivers/clocksource/Kconfig
>> @@ -641,6 +641,17 @@ config RISCV_TIMER
>> is accessed via both the SBI and the rdcycle instruction. This is
>> required for all RISC-V systems.
>> +config STARFIVE_JH7110_TIMER
>> + bool "Timer for the STARFIVE JH7110 SoC"
>> + depends on ARCH_STARFIVE || COMPILE_TEST
>
> You may want to use ARCH_STARFIVE only if the platform can make this timer optional. Otherwise, set the option from the platform Kconfig and put the bool "bla bla" if COMPILE_TEST
Yes, this timer only be used on the StarFive SoC. So I intend to modify to this:
bool "Timer for the STARFIVE JH7110 SoC" if COMPILE_TEST
depends on ARCH_STARFIVE
>
>> + select TIMER_OF
>> + select CLKSRC_MMIO
>> + default ARCH_STARFIVE
>
> no "default"
Will drop it.
>
>> + help
>> + This enables the timer for StarFive JH7110 SoC. On RISC-V platform,
>> + the system has started RISCV_TIMER, but you can also use this timer
>> + which can provide four channels to do a lot more things on JH7110 SoC.
>> +
>> config CLINT_TIMER
>> bool "CLINT Timer for the RISC-V platform" if COMPILE_TEST
>> depends on GENERIC_SCHED_CLOCK && RISCV
>> diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
>> index 368c3461dab8..b66ac05ec086 100644
>> --- a/drivers/clocksource/Makefile
>> +++ b/drivers/clocksource/Makefile
>> @@ -80,6 +80,7 @@ obj-$(CONFIG_INGENIC_TIMER) += ingenic-timer.o
>> obj-$(CONFIG_CLKSRC_ST_LPC) += clksrc_st_lpc.o
>> obj-$(CONFIG_X86_NUMACHIP) += numachip.o
>> obj-$(CONFIG_RISCV_TIMER) += timer-riscv.o
>> +obj-$(CONFIG_STARFIVE_JH7110_TIMER) += timer-jh7110.o
>> obj-$(CONFIG_CLINT_TIMER) += timer-clint.o
>> obj-$(CONFIG_CSKY_MP_TIMER) += timer-mp-csky.o
>> obj-$(CONFIG_GX6605S_TIMER) += timer-gx6605s.o
>> diff --git a/drivers/clocksource/timer-jh7110.c b/drivers/clocksource/timer-jh7110.c
>> new file mode 100644
>> index 000000000000..71de29a3ec91
>> --- /dev/null
>> +++ b/drivers/clocksource/timer-jh7110.c
>> @@ -0,0 +1,380 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Starfive JH7110 Timer driver
>> + *
>> + * Copyright (C) 2022-2023 StarFive Technology Co., Ltd.
>> + *
>> + * Author:
>> + * Xingyu Wu <xingyu.wu at starfivetech.com>
>> + * Samin Guo <samin.guo at starfivetech.com>
>> + */
>> +
>> +#include <linux/clk.h>
>> +#include <linux/clockchips.h>
>> +#include <linux/clocksource.h>
>> +#include <linux/err.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/io.h>
>> +#include <linux/iopoll.h>
>> +#include <linux/irq.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/reset.h>
>> +#include <linux/sched_clock.h>
>
> Please double check the headers and remove the pointless ones.
Will fix.
>
>
>> +/* Bias: Ch0-0x0, Ch1-0x40, Ch2-0x80, and so on. */
>> +#define JH7110_TIMER_CH_LEN 0x40
>> +#define JH7110_TIMER_CH_BASE(x) ((x) * JH7110_TIMER_CH_LEN)
>> +#define JH7110_TIMER_CH_MAX 4
>> +
>> +#define JH7110_CLOCK_SOURCE_RATING 200
>> +#define JH7110_VALID_BITS 32
>> +#define JH7110_DELAY_US 0
>> +#define JH7110_TIMEOUT_US 10000
>> +#define JH7110_CLOCKEVENT_RATING 300
>> +#define JH7110_TIMER_MAX_TICKS 0xffffffff
>> +#define JH7110_TIMER_MIN_TICKS 0xf
>> +#define JH7110_TIMER_RELOAD_VALUE 0
>> +
>> +#define JH7110_TIMER_INT_STATUS 0x00 /* RO[0:4]: Interrupt Status for channel0~4 */
>> +#define JH7110_TIMER_CTL 0x04 /* RW[0]: 0-continuous run, 1-single run */
>> +#define JH7110_TIMER_LOAD 0x08 /* RW: load value to counter */
>> +#define JH7110_TIMER_ENABLE 0x10 /* RW[0]: timer enable register */
>> +#define JH7110_TIMER_RELOAD 0x14 /* RW: write 1 or 0 both reload counter */
>> +#define JH7110_TIMER_VALUE 0x18 /* RO: timer value register */
>> +#define JH7110_TIMER_INT_CLR 0x20 /* RW: timer interrupt clear register */
>> +#define JH7110_TIMER_INT_MASK 0x24 /* RW[0]: timer interrupt mask register */
>> +
>> +#define JH7110_TIMER_INT_CLR_ENA BIT(0)
>> +#define JH7110_TIMER_INT_CLR_AVA_MASK BIT(1)
>> +
>> +struct jh7110_clkevt {
>> + struct clock_event_device evt;
>> + struct clocksource cs;
>> + bool cs_is_valid;
>> + struct clk *clk;
>> + struct reset_control *rst;
>> + u32 rate;
>> + u32 reload_val;
>> + void __iomem *base;
>> + char name[sizeof("jh7110-timer.chX")];
>> +};
>> +
>> +struct jh7110_timer_priv {
>> + struct clk *pclk;
>> + struct reset_control *prst;
>> + struct jh7110_clkevt clkevt[JH7110_TIMER_CH_MAX];
>
> Why do you need several clock events and clock sources ?
This timer has four counters (channels) which run independently. So each counter can have its own clock event and clock source to configure different settings.
>
> [ ... ]
>
>
Thanks,
Xingyu Wu
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