Re: [PATCH v2 06/15] clocksource/drivers/timer-milbeaut: Introduce timer for Milbeaut SoCs

From: Daniel Lezcano
Date: Thu Feb 14 2019 - 10:23:04 EST


On 08/02/2019 13:26, Sugaya Taichi wrote:
> 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@xxxxxxxxxxxxx>

Acked-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>

> ---
> drivers/clocksource/Kconfig | 9 ++
> drivers/clocksource/Makefile | 1 +
> drivers/clocksource/timer-milbeaut.c | 161 +++++++++++++++++++++++++++++++++++
> 3 files changed, 171 insertions(+)
> create mode 100644 drivers/clocksource/timer-milbeaut.c
>
> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
> index a9e26f6..9101b8f 100644
> --- a/drivers/clocksource/Kconfig
> +++ b/drivers/clocksource/Kconfig
> @@ -634,4 +634,13 @@ config GX6605S_TIMER
> help
> This option enables support for gx6605s SOC's timer.
>
> +config MILBEAUT_TIMER
> + bool "Milbeaut timer driver" if COMPILE_TEST
> + depends on OF
> + depends on ARM
> + select TIMER_OF
> + select CLKSRC_MMIO
> + help
> + Enables the support for Milbeaut timer driver.
> +
> endmenu
> diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
> index cdd210f..6f2543b 100644
> --- a/drivers/clocksource/Makefile
> +++ b/drivers/clocksource/Makefile
> @@ -55,6 +55,7 @@ obj-$(CONFIG_CLKSRC_TI_32K) += timer-ti-32k.o
> obj-$(CONFIG_CLKSRC_NPS) += timer-nps.o
> obj-$(CONFIG_OXNAS_RPS_TIMER) += timer-oxnas-rps.o
> obj-$(CONFIG_OWL_TIMER) += timer-owl.o
> +obj-$(CONFIG_MILBEAUT_TIMER) += timer-milbeaut.o
> obj-$(CONFIG_SPRD_TIMER) += timer-sprd.o
> obj-$(CONFIG_NPCM7XX_TIMER) += timer-npcm7xx.o
> obj-$(CONFIG_RDA_TIMER) += timer-rda.o
> diff --git a/drivers/clocksource/timer-milbeaut.c b/drivers/clocksource/timer-milbeaut.c
> new file mode 100644
> index 0000000..f2019a8
> --- /dev/null
> +++ b/drivers/clocksource/timer-milbeaut.c
> @@ -0,0 +1,161 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2018 Socionext Inc.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/irqreturn.h>
> +#include <linux/sched_clock.h>
> +#include "timer-of.h"
> +
> +#define MLB_TMR_TMCSR_OFS 0x0
> +#define MLB_TMR_TMR_OFS 0x4
> +#define MLB_TMR_TMRLR1_OFS 0x8
> +#define MLB_TMR_TMRLR2_OFS 0xc
> +#define MLB_TMR_REGSZPCH 0x10
> +
> +#define MLB_TMR_TMCSR_OUTL BIT(5)
> +#define MLB_TMR_TMCSR_RELD BIT(4)
> +#define MLB_TMR_TMCSR_INTE BIT(3)
> +#define MLB_TMR_TMCSR_UF BIT(2)
> +#define MLB_TMR_TMCSR_CNTE BIT(1)
> +#define MLB_TMR_TMCSR_TRG BIT(0)
> +
> +#define MLB_TMR_TMCSR_CSL_DIV2 0
> +#define MLB_TMR_DIV_CNT 2
> +
> +#define MLB_TMR_SRC_CH (1)
> +#define MLB_TMR_EVT_CH (0)
> +
> +#define MLB_TMR_SRC_CH_OFS (MLB_TMR_REGSZPCH * MLB_TMR_SRC_CH)
> +#define MLB_TMR_EVT_CH_OFS (MLB_TMR_REGSZPCH * MLB_TMR_EVT_CH)
> +
> +#define MLB_TMR_SRC_TMCSR_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMCSR_OFS)
> +#define MLB_TMR_SRC_TMR_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMR_OFS)
> +#define MLB_TMR_SRC_TMRLR1_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMRLR1_OFS)
> +#define MLB_TMR_SRC_TMRLR2_OFS (MLB_TMR_SRC_CH_OFS + MLB_TMR_TMRLR2_OFS)
> +
> +#define MLB_TMR_EVT_TMCSR_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMCSR_OFS)
> +#define MLB_TMR_EVT_TMR_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMR_OFS)
> +#define MLB_TMR_EVT_TMRLR1_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR1_OFS)
> +#define MLB_TMR_EVT_TMRLR2_OFS (MLB_TMR_EVT_CH_OFS + MLB_TMR_TMRLR2_OFS)
> +
> +#define MLB_TIMER_RATING 500
> +
> +static irqreturn_t mlb_timer_interrupt(int irq, void *dev_id)
> +{
> + struct clock_event_device *clk = dev_id;
> + struct timer_of *to = to_timer_of(clk);
> + u32 val;
> +
> + val = readl_relaxed(timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
> + val &= ~MLB_TMR_TMCSR_UF;
> + writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
> +
> + clk->event_handler(clk);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int mlb_set_state_periodic(struct clock_event_device *clk)
> +{
> + struct timer_of *to = to_timer_of(clk);
> + u32 val = MLB_TMR_TMCSR_CSL_DIV2;
> +
> + writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
> +
> + writel_relaxed(to->of_clk.period, timer_of_base(to) +
> + MLB_TMR_EVT_TMRLR1_OFS);
> + val |= MLB_TMR_TMCSR_RELD | MLB_TMR_TMCSR_CNTE |
> + MLB_TMR_TMCSR_TRG | MLB_TMR_TMCSR_INTE;
> + writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
> + return 0;
> +}
> +
> +static int mlb_set_state_oneshot(struct clock_event_device *clk)
> +{
> + struct timer_of *to = to_timer_of(clk);
> + u32 val = MLB_TMR_TMCSR_CSL_DIV2;
> +
> + writel_relaxed(val, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
> + return 0;
> +}
> +
> +static int mlb_clkevt_next_event(unsigned long event,
> + struct clock_event_device *clk)
> +{
> + struct timer_of *to = to_timer_of(clk);
> +
> + writel_relaxed(event, timer_of_base(to) + MLB_TMR_EVT_TMRLR1_OFS);
> + writel_relaxed(MLB_TMR_TMCSR_CSL_DIV2 |
> + MLB_TMR_TMCSR_CNTE | MLB_TMR_TMCSR_INTE |
> + MLB_TMR_TMCSR_TRG, timer_of_base(to) +
> + MLB_TMR_EVT_TMCSR_OFS);
> + return 0;
> +}
> +
> +static int mlb_config_clock_source(struct timer_of *to)
> +{
> + writel_relaxed(0, timer_of_base(to) + MLB_TMR_SRC_TMCSR_OFS);
> + writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMR_OFS);
> + writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR1_OFS);
> + writel_relaxed(~0, timer_of_base(to) + MLB_TMR_SRC_TMRLR2_OFS);
> + writel_relaxed(BIT(4) | BIT(1) | BIT(0), timer_of_base(to) +
> + MLB_TMR_SRC_TMCSR_OFS);
> + return 0;
> +}
> +
> +static int mlb_config_clock_event(struct timer_of *to)
> +{
> + writel_relaxed(0, timer_of_base(to) + MLB_TMR_EVT_TMCSR_OFS);
> + return 0;
> +}
> +
> +static struct timer_of to = {
> + .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
> +
> + .clkevt = {
> + .name = "mlb-clkevt",
> + .rating = MLB_TIMER_RATING,
> + .cpumask = cpu_possible_mask,
> + .features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_ONESHOT,
> + .set_state_oneshot = mlb_set_state_oneshot,
> + .set_state_periodic = mlb_set_state_periodic,
> + .set_next_event = mlb_clkevt_next_event,
> + },
> +
> + .of_irq = {
> + .flags = IRQF_TIMER | IRQF_IRQPOLL,
> + .handler = mlb_timer_interrupt,
> + },
> +};
> +
> +static u64 notrace mlb_timer_sched_read(void)
> +{
> + return ~readl_relaxed(timer_of_base(&to) + MLB_TMR_SRC_TMR_OFS);
> +}
> +
> +static int __init mlb_timer_init(struct device_node *node)
> +{
> + int ret;
> + unsigned long rate;
> +
> + ret = timer_of_init(node, &to);
> + if (ret)
> + return ret;
> +
> + rate = timer_of_rate(&to) / MLB_TMR_DIV_CNT;
> + mlb_config_clock_source(&to);
> + clocksource_mmio_init(timer_of_base(&to) + MLB_TMR_SRC_TMR_OFS,
> + node->name, rate, MLB_TIMER_RATING, 32,
> + clocksource_mmio_readl_down);
> + sched_clock_register(mlb_timer_sched_read, 32, rate);
> + mlb_config_clock_event(&to);
> + clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), 15,
> + 0xffffffff);
> + return 0;
> +}
> +TIMER_OF_DECLARE(mlb_peritimer, "socionext,milbeaut-timer",
> + mlb_timer_init);
>


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