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ec3372f28f
shutdown and oneshot are already protected against irq interruptions Signed-off-by: Clément Péron <peron.clem@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
531 lines
14 KiB
C
531 lines
14 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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//
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// Copyright (C) 2000-2001 Deep Blue Solutions
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// Copyright (C) 2002 Shane Nay (shane@minirl.com)
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// Copyright (C) 2006-2007 Pavel Pisa (ppisa@pikron.com)
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// Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de)
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <linux/clockchips.h>
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/err.h>
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#include <linux/sched_clock.h>
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#include <linux/slab.h>
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#include <linux/of.h>
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#include <linux/of_address.h>
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#include <linux/of_irq.h>
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#include <soc/imx/timer.h>
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/*
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* There are 4 versions of the timer hardware on Freescale MXC hardware.
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* - MX1/MXL
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* - MX21, MX27.
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* - MX25, MX31, MX35, MX37, MX51, MX6Q(rev1.0)
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* - MX6DL, MX6SX, MX6Q(rev1.1+)
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*/
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/* defines common for all i.MX */
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#define MXC_TCTL 0x00
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#define MXC_TCTL_TEN (1 << 0) /* Enable module */
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#define MXC_TPRER 0x04
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/* MX1, MX21, MX27 */
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#define MX1_2_TCTL_CLK_PCLK1 (1 << 1)
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#define MX1_2_TCTL_IRQEN (1 << 4)
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#define MX1_2_TCTL_FRR (1 << 8)
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#define MX1_2_TCMP 0x08
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#define MX1_2_TCN 0x10
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#define MX1_2_TSTAT 0x14
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/* MX21, MX27 */
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#define MX2_TSTAT_CAPT (1 << 1)
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#define MX2_TSTAT_COMP (1 << 0)
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/* MX31, MX35, MX25, MX5, MX6 */
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#define V2_TCTL_WAITEN (1 << 3) /* Wait enable mode */
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#define V2_TCTL_CLK_IPG (1 << 6)
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#define V2_TCTL_CLK_PER (2 << 6)
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#define V2_TCTL_CLK_OSC_DIV8 (5 << 6)
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#define V2_TCTL_FRR (1 << 9)
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#define V2_TCTL_24MEN (1 << 10)
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#define V2_TPRER_PRE24M 12
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#define V2_IR 0x0c
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#define V2_TSTAT 0x08
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#define V2_TSTAT_OF1 (1 << 0)
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#define V2_TCN 0x24
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#define V2_TCMP 0x10
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#define V2_TIMER_RATE_OSC_DIV8 3000000
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struct imx_timer {
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enum imx_gpt_type type;
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void __iomem *base;
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int irq;
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struct clk *clk_per;
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struct clk *clk_ipg;
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const struct imx_gpt_data *gpt;
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struct clock_event_device ced;
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struct irqaction act;
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};
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struct imx_gpt_data {
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int reg_tstat;
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int reg_tcn;
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int reg_tcmp;
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void (*gpt_setup_tctl)(struct imx_timer *imxtm);
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void (*gpt_irq_enable)(struct imx_timer *imxtm);
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void (*gpt_irq_disable)(struct imx_timer *imxtm);
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void (*gpt_irq_acknowledge)(struct imx_timer *imxtm);
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int (*set_next_event)(unsigned long evt,
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struct clock_event_device *ced);
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};
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static inline struct imx_timer *to_imx_timer(struct clock_event_device *ced)
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{
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return container_of(ced, struct imx_timer, ced);
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}
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static void imx1_gpt_irq_disable(struct imx_timer *imxtm)
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{
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unsigned int tmp;
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tmp = readl_relaxed(imxtm->base + MXC_TCTL);
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writel_relaxed(tmp & ~MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL);
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}
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#define imx21_gpt_irq_disable imx1_gpt_irq_disable
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static void imx31_gpt_irq_disable(struct imx_timer *imxtm)
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{
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writel_relaxed(0, imxtm->base + V2_IR);
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}
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#define imx6dl_gpt_irq_disable imx31_gpt_irq_disable
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static void imx1_gpt_irq_enable(struct imx_timer *imxtm)
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{
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unsigned int tmp;
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tmp = readl_relaxed(imxtm->base + MXC_TCTL);
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writel_relaxed(tmp | MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL);
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}
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#define imx21_gpt_irq_enable imx1_gpt_irq_enable
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static void imx31_gpt_irq_enable(struct imx_timer *imxtm)
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{
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writel_relaxed(1<<0, imxtm->base + V2_IR);
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}
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#define imx6dl_gpt_irq_enable imx31_gpt_irq_enable
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static void imx1_gpt_irq_acknowledge(struct imx_timer *imxtm)
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{
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writel_relaxed(0, imxtm->base + MX1_2_TSTAT);
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}
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static void imx21_gpt_irq_acknowledge(struct imx_timer *imxtm)
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{
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writel_relaxed(MX2_TSTAT_CAPT | MX2_TSTAT_COMP,
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imxtm->base + MX1_2_TSTAT);
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}
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static void imx31_gpt_irq_acknowledge(struct imx_timer *imxtm)
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{
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writel_relaxed(V2_TSTAT_OF1, imxtm->base + V2_TSTAT);
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}
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#define imx6dl_gpt_irq_acknowledge imx31_gpt_irq_acknowledge
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static void __iomem *sched_clock_reg;
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static u64 notrace mxc_read_sched_clock(void)
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{
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return sched_clock_reg ? readl_relaxed(sched_clock_reg) : 0;
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}
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#if defined(CONFIG_ARM)
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static struct delay_timer imx_delay_timer;
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static unsigned long imx_read_current_timer(void)
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{
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return readl_relaxed(sched_clock_reg);
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}
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#endif
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static int __init mxc_clocksource_init(struct imx_timer *imxtm)
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{
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unsigned int c = clk_get_rate(imxtm->clk_per);
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void __iomem *reg = imxtm->base + imxtm->gpt->reg_tcn;
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#if defined(CONFIG_ARM)
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imx_delay_timer.read_current_timer = &imx_read_current_timer;
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imx_delay_timer.freq = c;
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register_current_timer_delay(&imx_delay_timer);
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#endif
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sched_clock_reg = reg;
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sched_clock_register(mxc_read_sched_clock, 32, c);
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return clocksource_mmio_init(reg, "mxc_timer1", c, 200, 32,
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clocksource_mmio_readl_up);
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}
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/* clock event */
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static int mx1_2_set_next_event(unsigned long evt,
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struct clock_event_device *ced)
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{
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struct imx_timer *imxtm = to_imx_timer(ced);
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unsigned long tcmp;
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tcmp = readl_relaxed(imxtm->base + MX1_2_TCN) + evt;
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writel_relaxed(tcmp, imxtm->base + MX1_2_TCMP);
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return (int)(tcmp - readl_relaxed(imxtm->base + MX1_2_TCN)) < 0 ?
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-ETIME : 0;
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}
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static int v2_set_next_event(unsigned long evt,
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struct clock_event_device *ced)
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{
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struct imx_timer *imxtm = to_imx_timer(ced);
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unsigned long tcmp;
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tcmp = readl_relaxed(imxtm->base + V2_TCN) + evt;
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writel_relaxed(tcmp, imxtm->base + V2_TCMP);
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return evt < 0x7fffffff &&
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(int)(tcmp - readl_relaxed(imxtm->base + V2_TCN)) < 0 ?
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-ETIME : 0;
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}
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static int mxc_shutdown(struct clock_event_device *ced)
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{
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struct imx_timer *imxtm = to_imx_timer(ced);
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u32 tcn;
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/* Disable interrupt in GPT module */
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imxtm->gpt->gpt_irq_disable(imxtm);
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tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn);
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/* Set event time into far-far future */
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writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp);
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/* Clear pending interrupt */
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imxtm->gpt->gpt_irq_acknowledge(imxtm);
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#ifdef DEBUG
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printk(KERN_INFO "%s: changing mode\n", __func__);
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#endif /* DEBUG */
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return 0;
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}
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static int mxc_set_oneshot(struct clock_event_device *ced)
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{
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struct imx_timer *imxtm = to_imx_timer(ced);
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/* Disable interrupt in GPT module */
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imxtm->gpt->gpt_irq_disable(imxtm);
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if (!clockevent_state_oneshot(ced)) {
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u32 tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn);
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/* Set event time into far-far future */
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writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp);
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/* Clear pending interrupt */
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imxtm->gpt->gpt_irq_acknowledge(imxtm);
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}
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#ifdef DEBUG
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printk(KERN_INFO "%s: changing mode\n", __func__);
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#endif /* DEBUG */
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/*
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* Do not put overhead of interrupt enable/disable into
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* mxc_set_next_event(), the core has about 4 minutes
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* to call mxc_set_next_event() or shutdown clock after
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* mode switching
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*/
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imxtm->gpt->gpt_irq_enable(imxtm);
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return 0;
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}
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/*
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* IRQ handler for the timer
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*/
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static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id)
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{
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struct clock_event_device *ced = dev_id;
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struct imx_timer *imxtm = to_imx_timer(ced);
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uint32_t tstat;
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tstat = readl_relaxed(imxtm->base + imxtm->gpt->reg_tstat);
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imxtm->gpt->gpt_irq_acknowledge(imxtm);
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ced->event_handler(ced);
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return IRQ_HANDLED;
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}
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static int __init mxc_clockevent_init(struct imx_timer *imxtm)
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{
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struct clock_event_device *ced = &imxtm->ced;
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struct irqaction *act = &imxtm->act;
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ced->name = "mxc_timer1";
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ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ;
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ced->set_state_shutdown = mxc_shutdown;
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ced->set_state_oneshot = mxc_set_oneshot;
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ced->tick_resume = mxc_shutdown;
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ced->set_next_event = imxtm->gpt->set_next_event;
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ced->rating = 200;
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ced->cpumask = cpumask_of(0);
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ced->irq = imxtm->irq;
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clockevents_config_and_register(ced, clk_get_rate(imxtm->clk_per),
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0xff, 0xfffffffe);
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act->name = "i.MX Timer Tick";
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act->flags = IRQF_TIMER | IRQF_IRQPOLL;
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act->handler = mxc_timer_interrupt;
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act->dev_id = ced;
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return setup_irq(imxtm->irq, act);
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}
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static void imx1_gpt_setup_tctl(struct imx_timer *imxtm)
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{
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u32 tctl_val;
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tctl_val = MX1_2_TCTL_FRR | MX1_2_TCTL_CLK_PCLK1 | MXC_TCTL_TEN;
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writel_relaxed(tctl_val, imxtm->base + MXC_TCTL);
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}
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#define imx21_gpt_setup_tctl imx1_gpt_setup_tctl
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static void imx31_gpt_setup_tctl(struct imx_timer *imxtm)
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{
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u32 tctl_val;
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tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN;
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if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8)
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tctl_val |= V2_TCTL_CLK_OSC_DIV8;
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else
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tctl_val |= V2_TCTL_CLK_PER;
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writel_relaxed(tctl_val, imxtm->base + MXC_TCTL);
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}
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static void imx6dl_gpt_setup_tctl(struct imx_timer *imxtm)
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{
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u32 tctl_val;
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tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN;
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if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8) {
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tctl_val |= V2_TCTL_CLK_OSC_DIV8;
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/* 24 / 8 = 3 MHz */
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writel_relaxed(7 << V2_TPRER_PRE24M, imxtm->base + MXC_TPRER);
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tctl_val |= V2_TCTL_24MEN;
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} else {
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tctl_val |= V2_TCTL_CLK_PER;
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}
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writel_relaxed(tctl_val, imxtm->base + MXC_TCTL);
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}
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static const struct imx_gpt_data imx1_gpt_data = {
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.reg_tstat = MX1_2_TSTAT,
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.reg_tcn = MX1_2_TCN,
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.reg_tcmp = MX1_2_TCMP,
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.gpt_irq_enable = imx1_gpt_irq_enable,
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.gpt_irq_disable = imx1_gpt_irq_disable,
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.gpt_irq_acknowledge = imx1_gpt_irq_acknowledge,
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.gpt_setup_tctl = imx1_gpt_setup_tctl,
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.set_next_event = mx1_2_set_next_event,
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};
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static const struct imx_gpt_data imx21_gpt_data = {
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.reg_tstat = MX1_2_TSTAT,
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.reg_tcn = MX1_2_TCN,
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.reg_tcmp = MX1_2_TCMP,
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.gpt_irq_enable = imx21_gpt_irq_enable,
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.gpt_irq_disable = imx21_gpt_irq_disable,
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.gpt_irq_acknowledge = imx21_gpt_irq_acknowledge,
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.gpt_setup_tctl = imx21_gpt_setup_tctl,
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.set_next_event = mx1_2_set_next_event,
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};
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static const struct imx_gpt_data imx31_gpt_data = {
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.reg_tstat = V2_TSTAT,
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.reg_tcn = V2_TCN,
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.reg_tcmp = V2_TCMP,
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.gpt_irq_enable = imx31_gpt_irq_enable,
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.gpt_irq_disable = imx31_gpt_irq_disable,
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.gpt_irq_acknowledge = imx31_gpt_irq_acknowledge,
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.gpt_setup_tctl = imx31_gpt_setup_tctl,
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.set_next_event = v2_set_next_event,
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};
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static const struct imx_gpt_data imx6dl_gpt_data = {
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.reg_tstat = V2_TSTAT,
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.reg_tcn = V2_TCN,
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.reg_tcmp = V2_TCMP,
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.gpt_irq_enable = imx6dl_gpt_irq_enable,
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.gpt_irq_disable = imx6dl_gpt_irq_disable,
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.gpt_irq_acknowledge = imx6dl_gpt_irq_acknowledge,
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.gpt_setup_tctl = imx6dl_gpt_setup_tctl,
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.set_next_event = v2_set_next_event,
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};
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static int __init _mxc_timer_init(struct imx_timer *imxtm)
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{
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int ret;
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switch (imxtm->type) {
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case GPT_TYPE_IMX1:
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imxtm->gpt = &imx1_gpt_data;
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break;
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case GPT_TYPE_IMX21:
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imxtm->gpt = &imx21_gpt_data;
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break;
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case GPT_TYPE_IMX31:
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imxtm->gpt = &imx31_gpt_data;
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break;
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case GPT_TYPE_IMX6DL:
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imxtm->gpt = &imx6dl_gpt_data;
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break;
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default:
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return -EINVAL;
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}
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if (IS_ERR(imxtm->clk_per)) {
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pr_err("i.MX timer: unable to get clk\n");
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return PTR_ERR(imxtm->clk_per);
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}
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if (!IS_ERR(imxtm->clk_ipg))
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clk_prepare_enable(imxtm->clk_ipg);
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clk_prepare_enable(imxtm->clk_per);
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/*
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* Initialise to a known state (all timers off, and timing reset)
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*/
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writel_relaxed(0, imxtm->base + MXC_TCTL);
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writel_relaxed(0, imxtm->base + MXC_TPRER); /* see datasheet note */
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imxtm->gpt->gpt_setup_tctl(imxtm);
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/* init and register the timer to the framework */
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ret = mxc_clocksource_init(imxtm);
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if (ret)
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return ret;
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return mxc_clockevent_init(imxtm);
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}
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void __init mxc_timer_init(unsigned long pbase, int irq, enum imx_gpt_type type)
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{
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struct imx_timer *imxtm;
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imxtm = kzalloc(sizeof(*imxtm), GFP_KERNEL);
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BUG_ON(!imxtm);
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imxtm->clk_per = clk_get_sys("imx-gpt.0", "per");
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imxtm->clk_ipg = clk_get_sys("imx-gpt.0", "ipg");
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imxtm->base = ioremap(pbase, SZ_4K);
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BUG_ON(!imxtm->base);
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imxtm->type = type;
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imxtm->irq = irq;
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_mxc_timer_init(imxtm);
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}
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static int __init mxc_timer_init_dt(struct device_node *np, enum imx_gpt_type type)
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{
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struct imx_timer *imxtm;
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|
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)
|
|
return -ENXIO;
|
|
|
|
imxtm->irq = irq_of_parse_and_map(np, 0);
|
|
if (imxtm->irq <= 0)
|
|
return -EINVAL;
|
|
|
|
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)
|
|
return ret;
|
|
|
|
initialized = 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
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);
|