diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/clocksource/timer-imx-gpt.c | 532 |
1 files changed, 532 insertions, 0 deletions
diff --git a/drivers/clocksource/timer-imx-gpt.c b/drivers/clocksource/timer-imx-gpt.c new file mode 100644 index 000000000..fabff69e5 --- /dev/null +++ b/drivers/clocksource/timer-imx-gpt.c @@ -0,0 +1,532 @@ +// SPDX-License-Identifier: GPL-2.0+ +// +// Copyright (C) 2000-2001 Deep Blue Solutions +// Copyright (C) 2002 Shane Nay (shane@minirl.com) +// Copyright (C) 2006-2007 Pavel Pisa (ppisa@pikron.com) +// Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de) + +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/clockchips.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/sched_clock.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <soc/imx/timer.h> + +/* + * There are 4 versions of the timer hardware on Freescale MXC hardware. + * - MX1/MXL + * - MX21, MX27. + * - MX25, MX31, MX35, MX37, MX51, MX6Q(rev1.0) + * - MX6DL, MX6SX, MX6Q(rev1.1+) + */ + +/* defines common for all i.MX */ +#define MXC_TCTL 0x00 +#define MXC_TCTL_TEN (1 << 0) /* Enable module */ +#define MXC_TPRER 0x04 + +/* MX1, MX21, MX27 */ +#define MX1_2_TCTL_CLK_PCLK1 (1 << 1) +#define MX1_2_TCTL_IRQEN (1 << 4) +#define MX1_2_TCTL_FRR (1 << 8) +#define MX1_2_TCMP 0x08 +#define MX1_2_TCN 0x10 +#define MX1_2_TSTAT 0x14 + +/* MX21, MX27 */ +#define MX2_TSTAT_CAPT (1 << 1) +#define MX2_TSTAT_COMP (1 << 0) + +/* MX31, MX35, MX25, MX5, MX6 */ +#define V2_TCTL_WAITEN (1 << 3) /* Wait enable mode */ +#define V2_TCTL_CLK_IPG (1 << 6) +#define V2_TCTL_CLK_PER (2 << 6) +#define V2_TCTL_CLK_OSC_DIV8 (5 << 6) +#define V2_TCTL_FRR (1 << 9) +#define V2_TCTL_24MEN (1 << 10) +#define V2_TPRER_PRE24M 12 +#define V2_IR 0x0c +#define V2_TSTAT 0x08 +#define V2_TSTAT_OF1 (1 << 0) +#define V2_TCN 0x24 +#define V2_TCMP 0x10 + +#define V2_TIMER_RATE_OSC_DIV8 3000000 + +struct imx_timer { + enum imx_gpt_type type; + void __iomem *base; + int irq; + struct clk *clk_per; + struct clk *clk_ipg; + const struct imx_gpt_data *gpt; + struct clock_event_device ced; +}; + +struct imx_gpt_data { + int reg_tstat; + int reg_tcn; + int reg_tcmp; + void (*gpt_setup_tctl)(struct imx_timer *imxtm); + void (*gpt_irq_enable)(struct imx_timer *imxtm); + void (*gpt_irq_disable)(struct imx_timer *imxtm); + void (*gpt_irq_acknowledge)(struct imx_timer *imxtm); + int (*set_next_event)(unsigned long evt, + struct clock_event_device *ced); +}; + +static inline struct imx_timer *to_imx_timer(struct clock_event_device *ced) +{ + return container_of(ced, struct imx_timer, ced); +} + +static void imx1_gpt_irq_disable(struct imx_timer *imxtm) +{ + unsigned int tmp; + + tmp = readl_relaxed(imxtm->base + MXC_TCTL); + writel_relaxed(tmp & ~MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL); +} +#define imx21_gpt_irq_disable imx1_gpt_irq_disable + +static void imx31_gpt_irq_disable(struct imx_timer *imxtm) +{ + writel_relaxed(0, imxtm->base + V2_IR); +} +#define imx6dl_gpt_irq_disable imx31_gpt_irq_disable + +static void imx1_gpt_irq_enable(struct imx_timer *imxtm) +{ + unsigned int tmp; + + tmp = readl_relaxed(imxtm->base + MXC_TCTL); + writel_relaxed(tmp | MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL); +} +#define imx21_gpt_irq_enable imx1_gpt_irq_enable + +static void imx31_gpt_irq_enable(struct imx_timer *imxtm) +{ + writel_relaxed(1<<0, imxtm->base + V2_IR); +} +#define imx6dl_gpt_irq_enable imx31_gpt_irq_enable + +static void imx1_gpt_irq_acknowledge(struct imx_timer *imxtm) +{ + writel_relaxed(0, imxtm->base + MX1_2_TSTAT); +} + +static void imx21_gpt_irq_acknowledge(struct imx_timer *imxtm) +{ + writel_relaxed(MX2_TSTAT_CAPT | MX2_TSTAT_COMP, + imxtm->base + MX1_2_TSTAT); +} + +static void imx31_gpt_irq_acknowledge(struct imx_timer *imxtm) +{ + writel_relaxed(V2_TSTAT_OF1, imxtm->base + V2_TSTAT); +} +#define imx6dl_gpt_irq_acknowledge imx31_gpt_irq_acknowledge + +static void __iomem *sched_clock_reg; + +static u64 notrace mxc_read_sched_clock(void) +{ + return sched_clock_reg ? readl_relaxed(sched_clock_reg) : 0; +} + +#if defined(CONFIG_ARM) +static struct delay_timer imx_delay_timer; + +static unsigned long imx_read_current_timer(void) +{ + return readl_relaxed(sched_clock_reg); +} +#endif + +static int __init mxc_clocksource_init(struct imx_timer *imxtm) +{ + unsigned int c = clk_get_rate(imxtm->clk_per); + void __iomem *reg = imxtm->base + imxtm->gpt->reg_tcn; + +#if defined(CONFIG_ARM) + imx_delay_timer.read_current_timer = &imx_read_current_timer; + imx_delay_timer.freq = c; + register_current_timer_delay(&imx_delay_timer); +#endif + + sched_clock_reg = reg; + + sched_clock_register(mxc_read_sched_clock, 32, c); + return clocksource_mmio_init(reg, "mxc_timer1", c, 200, 32, + clocksource_mmio_readl_up); +} + +/* clock event */ + +static int mx1_2_set_next_event(unsigned long evt, + struct clock_event_device *ced) +{ + struct imx_timer *imxtm = to_imx_timer(ced); + unsigned long tcmp; + + tcmp = readl_relaxed(imxtm->base + MX1_2_TCN) + evt; + + writel_relaxed(tcmp, imxtm->base + MX1_2_TCMP); + + return (int)(tcmp - readl_relaxed(imxtm->base + MX1_2_TCN)) < 0 ? + -ETIME : 0; +} + +static int v2_set_next_event(unsigned long evt, + struct clock_event_device *ced) +{ + struct imx_timer *imxtm = to_imx_timer(ced); + unsigned long tcmp; + + tcmp = readl_relaxed(imxtm->base + V2_TCN) + evt; + + writel_relaxed(tcmp, imxtm->base + V2_TCMP); + + return evt < 0x7fffffff && + (int)(tcmp - readl_relaxed(imxtm->base + V2_TCN)) < 0 ? + -ETIME : 0; +} + +static int mxc_shutdown(struct clock_event_device *ced) +{ + struct imx_timer *imxtm = to_imx_timer(ced); + u32 tcn; + + /* Disable interrupt in GPT module */ + imxtm->gpt->gpt_irq_disable(imxtm); + + tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn); + /* Set event time into far-far future */ + writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp); + + /* Clear pending interrupt */ + imxtm->gpt->gpt_irq_acknowledge(imxtm); + +#ifdef DEBUG + printk(KERN_INFO "%s: changing mode\n", __func__); +#endif /* DEBUG */ + + return 0; +} + +static int mxc_set_oneshot(struct clock_event_device *ced) +{ + struct imx_timer *imxtm = to_imx_timer(ced); + + /* Disable interrupt in GPT module */ + imxtm->gpt->gpt_irq_disable(imxtm); + + if (!clockevent_state_oneshot(ced)) { + u32 tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn); + /* Set event time into far-far future */ + writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp); + + /* Clear pending interrupt */ + imxtm->gpt->gpt_irq_acknowledge(imxtm); + } + +#ifdef DEBUG + printk(KERN_INFO "%s: changing mode\n", __func__); +#endif /* DEBUG */ + + /* + * Do not put overhead of interrupt enable/disable into + * mxc_set_next_event(), the core has about 4 minutes + * to call mxc_set_next_event() or shutdown clock after + * mode switching + */ + imxtm->gpt->gpt_irq_enable(imxtm); + + return 0; +} + +/* + * IRQ handler for the timer + */ +static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id) +{ + struct clock_event_device *ced = dev_id; + struct imx_timer *imxtm = to_imx_timer(ced); + uint32_t tstat; + + tstat = readl_relaxed(imxtm->base + imxtm->gpt->reg_tstat); + + imxtm->gpt->gpt_irq_acknowledge(imxtm); + + ced->event_handler(ced); + + return IRQ_HANDLED; +} + +static int __init mxc_clockevent_init(struct imx_timer *imxtm) +{ + struct clock_event_device *ced = &imxtm->ced; + + ced->name = "mxc_timer1"; + ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ; + ced->set_state_shutdown = mxc_shutdown; + ced->set_state_oneshot = mxc_set_oneshot; + ced->tick_resume = mxc_shutdown; + ced->set_next_event = imxtm->gpt->set_next_event; + ced->rating = 200; + ced->cpumask = cpumask_of(0); + ced->irq = imxtm->irq; + clockevents_config_and_register(ced, clk_get_rate(imxtm->clk_per), + 0xff, 0xfffffffe); + + return request_irq(imxtm->irq, mxc_timer_interrupt, + IRQF_TIMER | IRQF_IRQPOLL, "i.MX Timer Tick", ced); +} + +static void imx1_gpt_setup_tctl(struct imx_timer *imxtm) +{ + u32 tctl_val; + + tctl_val = MX1_2_TCTL_FRR | MX1_2_TCTL_CLK_PCLK1 | MXC_TCTL_TEN; + writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); +} +#define imx21_gpt_setup_tctl imx1_gpt_setup_tctl + +static void imx31_gpt_setup_tctl(struct imx_timer *imxtm) +{ + u32 tctl_val; + + tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN; + if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8) + tctl_val |= V2_TCTL_CLK_OSC_DIV8; + else + tctl_val |= V2_TCTL_CLK_PER; + + writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); +} + +static void imx6dl_gpt_setup_tctl(struct imx_timer *imxtm) +{ + u32 tctl_val; + + tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN; + if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8) { + tctl_val |= V2_TCTL_CLK_OSC_DIV8; + /* 24 / 8 = 3 MHz */ + writel_relaxed(7 << V2_TPRER_PRE24M, imxtm->base + MXC_TPRER); + tctl_val |= V2_TCTL_24MEN; + } else { + tctl_val |= V2_TCTL_CLK_PER; + } + + writel_relaxed(tctl_val, imxtm->base + MXC_TCTL); +} + +static const struct imx_gpt_data imx1_gpt_data = { + .reg_tstat = MX1_2_TSTAT, + .reg_tcn = MX1_2_TCN, + .reg_tcmp = MX1_2_TCMP, + .gpt_irq_enable = imx1_gpt_irq_enable, + .gpt_irq_disable = imx1_gpt_irq_disable, + .gpt_irq_acknowledge = imx1_gpt_irq_acknowledge, + .gpt_setup_tctl = imx1_gpt_setup_tctl, + .set_next_event = mx1_2_set_next_event, +}; + +static const struct imx_gpt_data imx21_gpt_data = { + .reg_tstat = MX1_2_TSTAT, + .reg_tcn = MX1_2_TCN, + .reg_tcmp = MX1_2_TCMP, + .gpt_irq_enable = imx21_gpt_irq_enable, + .gpt_irq_disable = imx21_gpt_irq_disable, + .gpt_irq_acknowledge = imx21_gpt_irq_acknowledge, + .gpt_setup_tctl = imx21_gpt_setup_tctl, + .set_next_event = mx1_2_set_next_event, +}; + +static const struct imx_gpt_data imx31_gpt_data = { + .reg_tstat = V2_TSTAT, + .reg_tcn = V2_TCN, + .reg_tcmp = V2_TCMP, + .gpt_irq_enable = imx31_gpt_irq_enable, + .gpt_irq_disable = imx31_gpt_irq_disable, + .gpt_irq_acknowledge = imx31_gpt_irq_acknowledge, + .gpt_setup_tctl = imx31_gpt_setup_tctl, + .set_next_event = v2_set_next_event, +}; + +static const struct imx_gpt_data imx6dl_gpt_data = { + .reg_tstat = V2_TSTAT, + .reg_tcn = V2_TCN, + .reg_tcmp = V2_TCMP, + .gpt_irq_enable = imx6dl_gpt_irq_enable, + .gpt_irq_disable = imx6dl_gpt_irq_disable, + .gpt_irq_acknowledge = imx6dl_gpt_irq_acknowledge, + .gpt_setup_tctl = imx6dl_gpt_setup_tctl, + .set_next_event = v2_set_next_event, +}; + +static int __init _mxc_timer_init(struct imx_timer *imxtm) +{ + int ret; + + switch (imxtm->type) { + case GPT_TYPE_IMX1: + imxtm->gpt = &imx1_gpt_data; + break; + case GPT_TYPE_IMX21: + imxtm->gpt = &imx21_gpt_data; + break; + case GPT_TYPE_IMX31: + imxtm->gpt = &imx31_gpt_data; + break; + case GPT_TYPE_IMX6DL: + imxtm->gpt = &imx6dl_gpt_data; + break; + default: + return -EINVAL; + } + + if (IS_ERR(imxtm->clk_per)) { + pr_err("i.MX timer: unable to get clk\n"); + return PTR_ERR(imxtm->clk_per); + } + + if (!IS_ERR(imxtm->clk_ipg)) + clk_prepare_enable(imxtm->clk_ipg); + + clk_prepare_enable(imxtm->clk_per); + + /* + * Initialise to a known state (all timers off, and timing reset) + */ + + writel_relaxed(0, imxtm->base + MXC_TCTL); + writel_relaxed(0, imxtm->base + MXC_TPRER); /* see datasheet note */ + + imxtm->gpt->gpt_setup_tctl(imxtm); + + /* init and register the timer to the framework */ + ret = mxc_clocksource_init(imxtm); + if (ret) + return ret; + + return mxc_clockevent_init(imxtm); +} + +void __init mxc_timer_init(unsigned long pbase, int irq, enum imx_gpt_type type) +{ + struct imx_timer *imxtm; + + imxtm = kzalloc(sizeof(*imxtm), GFP_KERNEL); + BUG_ON(!imxtm); + + imxtm->clk_per = clk_get_sys("imx-gpt.0", "per"); + imxtm->clk_ipg = clk_get_sys("imx-gpt.0", "ipg"); + + imxtm->base = ioremap(pbase, SZ_4K); + BUG_ON(!imxtm->base); + + imxtm->type = type; + imxtm->irq = irq; + + _mxc_timer_init(imxtm); +} + +static int __init mxc_timer_init_dt(struct device_node *np, enum imx_gpt_type type) +{ + struct imx_timer *imxtm; + static int initialized; + int ret; + + /* Support one instance only */ + if (initialized) + return 0; + + imxtm = kzalloc(sizeof(*imxtm), GFP_KERNEL); + if (!imxtm) + return -ENOMEM; + + imxtm->base = of_iomap(np, 0); + if (!imxtm->base) { + ret = -ENXIO; + goto err_kfree; + } + + imxtm->irq = irq_of_parse_and_map(np, 0); + if (imxtm->irq <= 0) { + ret = -EINVAL; + goto err_kfree; + } + + imxtm->clk_ipg = of_clk_get_by_name(np, "ipg"); + + /* Try osc_per first, and fall back to per otherwise */ + imxtm->clk_per = of_clk_get_by_name(np, "osc_per"); + if (IS_ERR(imxtm->clk_per)) + imxtm->clk_per = of_clk_get_by_name(np, "per"); + + imxtm->type = type; + + ret = _mxc_timer_init(imxtm); + if (ret) + goto err_kfree; + + initialized = 1; + + return 0; + +err_kfree: + kfree(imxtm); + return ret; +} + +static int __init imx1_timer_init_dt(struct device_node *np) +{ + return mxc_timer_init_dt(np, GPT_TYPE_IMX1); +} + +static int __init imx21_timer_init_dt(struct device_node *np) +{ + return mxc_timer_init_dt(np, GPT_TYPE_IMX21); +} + +static int __init imx31_timer_init_dt(struct device_node *np) +{ + enum imx_gpt_type type = GPT_TYPE_IMX31; + + /* + * We were using the same compatible string for i.MX6Q/D and i.MX6DL/S + * GPT device, while they actually have different programming model. + * This is a workaround to keep the existing i.MX6DL/S DTBs continue + * working with the new kernel. + */ + if (of_machine_is_compatible("fsl,imx6dl")) + type = GPT_TYPE_IMX6DL; + + return mxc_timer_init_dt(np, type); +} + +static int __init imx6dl_timer_init_dt(struct device_node *np) +{ + return mxc_timer_init_dt(np, GPT_TYPE_IMX6DL); +} + +TIMER_OF_DECLARE(imx1_timer, "fsl,imx1-gpt", imx1_timer_init_dt); +TIMER_OF_DECLARE(imx21_timer, "fsl,imx21-gpt", imx21_timer_init_dt); +TIMER_OF_DECLARE(imx27_timer, "fsl,imx27-gpt", imx21_timer_init_dt); +TIMER_OF_DECLARE(imx31_timer, "fsl,imx31-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx25_timer, "fsl,imx25-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx50_timer, "fsl,imx50-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx51_timer, "fsl,imx51-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx53_timer, "fsl,imx53-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx6q_timer, "fsl,imx6q-gpt", imx31_timer_init_dt); +TIMER_OF_DECLARE(imx6dl_timer, "fsl,imx6dl-gpt", imx6dl_timer_init_dt); +TIMER_OF_DECLARE(imx6sl_timer, "fsl,imx6sl-gpt", imx6dl_timer_init_dt); +TIMER_OF_DECLARE(imx6sx_timer, "fsl,imx6sx-gpt", imx6dl_timer_init_dt); |