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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/clocksource/timer-gx6605s.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/clocksource/timer-gx6605s.c')
-rw-r--r-- | drivers/clocksource/timer-gx6605s.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-gx6605s.c b/drivers/clocksource/timer-gx6605s.c new file mode 100644 index 000000000..8d386adbe --- /dev/null +++ b/drivers/clocksource/timer-gx6605s.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/sched_clock.h> + +#include "timer-of.h" + +#define CLKSRC_OFFSET 0x40 + +#define TIMER_STATUS 0x00 +#define TIMER_VALUE 0x04 +#define TIMER_CONTRL 0x10 +#define TIMER_CONFIG 0x20 +#define TIMER_DIV 0x24 +#define TIMER_INI 0x28 + +#define GX6605S_STATUS_CLR BIT(0) +#define GX6605S_CONTRL_RST BIT(0) +#define GX6605S_CONTRL_START BIT(1) +#define GX6605S_CONFIG_EN BIT(0) +#define GX6605S_CONFIG_IRQ_EN BIT(1) + +static irqreturn_t gx6605s_timer_interrupt(int irq, void *dev) +{ + struct clock_event_device *ce = dev; + void __iomem *base = timer_of_base(to_timer_of(ce)); + + writel_relaxed(GX6605S_STATUS_CLR, base + TIMER_STATUS); + writel_relaxed(0, base + TIMER_INI); + + ce->event_handler(ce); + + return IRQ_HANDLED; +} + +static int gx6605s_timer_set_oneshot(struct clock_event_device *ce) +{ + void __iomem *base = timer_of_base(to_timer_of(ce)); + + /* reset and stop counter */ + writel_relaxed(GX6605S_CONTRL_RST, base + TIMER_CONTRL); + + /* enable with irq and start */ + writel_relaxed(GX6605S_CONFIG_EN | GX6605S_CONFIG_IRQ_EN, + base + TIMER_CONFIG); + + return 0; +} + +static int gx6605s_timer_set_next_event(unsigned long delta, + struct clock_event_device *ce) +{ + void __iomem *base = timer_of_base(to_timer_of(ce)); + + /* use reset to pause timer */ + writel_relaxed(GX6605S_CONTRL_RST, base + TIMER_CONTRL); + + /* config next timeout value */ + writel_relaxed(ULONG_MAX - delta, base + TIMER_INI); + writel_relaxed(GX6605S_CONTRL_START, base + TIMER_CONTRL); + + return 0; +} + +static int gx6605s_timer_shutdown(struct clock_event_device *ce) +{ + void __iomem *base = timer_of_base(to_timer_of(ce)); + + writel_relaxed(0, base + TIMER_CONTRL); + writel_relaxed(0, base + TIMER_CONFIG); + + return 0; +} + +static struct timer_of to = { + .flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK, + .clkevt = { + .rating = 300, + .features = CLOCK_EVT_FEAT_DYNIRQ | + CLOCK_EVT_FEAT_ONESHOT, + .set_state_shutdown = gx6605s_timer_shutdown, + .set_state_oneshot = gx6605s_timer_set_oneshot, + .set_next_event = gx6605s_timer_set_next_event, + .cpumask = cpu_possible_mask, + }, + .of_irq = { + .handler = gx6605s_timer_interrupt, + .flags = IRQF_TIMER | IRQF_IRQPOLL, + }, +}; + +static u64 notrace gx6605s_sched_clock_read(void) +{ + void __iomem *base; + + base = timer_of_base(&to) + CLKSRC_OFFSET; + + return (u64)readl_relaxed(base + TIMER_VALUE); +} + +static void gx6605s_clkevt_init(void __iomem *base) +{ + writel_relaxed(0, base + TIMER_DIV); + writel_relaxed(0, base + TIMER_CONFIG); + + clockevents_config_and_register(&to.clkevt, timer_of_rate(&to), 2, + ULONG_MAX); +} + +static int gx6605s_clksrc_init(void __iomem *base) +{ + writel_relaxed(0, base + TIMER_DIV); + writel_relaxed(0, base + TIMER_INI); + + writel_relaxed(GX6605S_CONTRL_RST, base + TIMER_CONTRL); + + writel_relaxed(GX6605S_CONFIG_EN, base + TIMER_CONFIG); + + writel_relaxed(GX6605S_CONTRL_START, base + TIMER_CONTRL); + + sched_clock_register(gx6605s_sched_clock_read, 32, timer_of_rate(&to)); + + return clocksource_mmio_init(base + TIMER_VALUE, "gx6605s", + timer_of_rate(&to), 200, 32, clocksource_mmio_readl_up); +} + +static int __init gx6605s_timer_init(struct device_node *np) +{ + int ret; + + /* + * The timer driver is for nationalchip gx6605s SOC and there are two + * same timer in gx6605s. We use one for clkevt and another for clksrc. + * + * The timer is mmio map to access, so we need give mmio address in dts. + * + * It provides a 32bit countup timer and interrupt will be caused by + * count-overflow. + * So we need set-next-event by ULONG_MAX - delta in TIMER_INI reg. + * + * The counter at 0x0 offset is clock event. + * The counter at 0x40 offset is clock source. + * They are the same in hardware, just different used by driver. + */ + ret = timer_of_init(np, &to); + if (ret) + return ret; + + gx6605s_clkevt_init(timer_of_base(&to)); + + return gx6605s_clksrc_init(timer_of_base(&to) + CLKSRC_OFFSET); +} +TIMER_OF_DECLARE(csky_gx6605s_timer, "csky,gx6605s-timer", gx6605s_timer_init); |