[PATCH 1/9] ARM: imx: move timer resources into a structure
Shenwei Wang
Shenwei.Wang at freescale.com
Fri May 15 09:36:18 PDT 2015
> -----Original Message-----
> From: shawnguo at kernel.org [mailto:shawnguo at kernel.org]
> Sent: 2015年5月15日 3:12
> To: linux-arm-kernel at lists.infradead.org
> Cc: kernel at pengutronix.de; Daniel Lezcano; Wang Shenwei-B38339; Shawn Guo
> Subject: [PATCH 1/9] ARM: imx: move timer resources into a structure
>
> From: Shawn Guo <shawn.guo at linaro.org>
>
> Instead of passing around as argument, let's move timer resources like irq and
> clocks together with base address into a data structure, and reference the
> resources from the struct variable directly to simplify the function call interface.
>
> Signed-off-by: Shawn Guo <shawn.guo at linaro.org>
> ---
> arch/arm/mach-imx/time.c | 119 ++++++++++++++++++++++++-----------------------
> 1 file changed, 61 insertions(+), 58 deletions(-)
>
> diff --git a/arch/arm/mach-imx/time.c b/arch/arm/mach-imx/time.c index
> ab5ee1c445f3..8ad7cb2a7f08 100644
> --- a/arch/arm/mach-imx/time.c
> +++ b/arch/arm/mach-imx/time.c
> @@ -84,27 +84,34 @@
> static struct clock_event_device clockevent_mxc; static enum
> clock_event_mode clockevent_mode = CLOCK_EVT_MODE_UNUSED;
>
> -static void __iomem *timer_base;
> +struct imx_timer {
> + void __iomem *base;
> + int irq;
> + struct clk *clk_per;
> + struct clk *clk_ipg;
> +};
> +
> +static struct imx_timer imxtm;
>
Since the changes still used a global variable to hold the information, it doesn't take advantage of what the clocksource framework provides, and make the driver unable to support multi-instances.
Regards,
Shenwei
> static inline void gpt_irq_disable(void) {
> unsigned int tmp;
>
> if (timer_is_v2())
> - __raw_writel(0, timer_base + V2_IR);
> + __raw_writel(0, imxtm.base + V2_IR);
> else {
> - tmp = __raw_readl(timer_base + MXC_TCTL);
> - __raw_writel(tmp & ~MX1_2_TCTL_IRQEN, timer_base + MXC_TCTL);
> + tmp = __raw_readl(imxtm.base + MXC_TCTL);
> + __raw_writel(tmp & ~MX1_2_TCTL_IRQEN, imxtm.base + MXC_TCTL);
> }
> }
>
> static inline void gpt_irq_enable(void) {
> if (timer_is_v2())
> - __raw_writel(1<<0, timer_base + V2_IR);
> + __raw_writel(1<<0, imxtm.base + V2_IR);
> else {
> - __raw_writel(__raw_readl(timer_base + MXC_TCTL) |
> MX1_2_TCTL_IRQEN,
> - timer_base + MXC_TCTL);
> + __raw_writel(__raw_readl(imxtm.base + MXC_TCTL) |
> MX1_2_TCTL_IRQEN,
> + imxtm.base + MXC_TCTL);
> }
> }
>
> @@ -112,12 +119,12 @@ static void gpt_irq_acknowledge(void) {
> if (timer_is_v1()) {
> if (cpu_is_mx1())
> - __raw_writel(0, timer_base + MX1_2_TSTAT);
> + __raw_writel(0, imxtm.base + MX1_2_TSTAT);
> else
> __raw_writel(MX2_TSTAT_CAPT | MX2_TSTAT_COMP,
> - timer_base + MX1_2_TSTAT);
> + imxtm.base + MX1_2_TSTAT);
> } else if (timer_is_v2())
> - __raw_writel(V2_TSTAT_OF1, timer_base + V2_TSTAT);
> + __raw_writel(V2_TSTAT_OF1, imxtm.base + V2_TSTAT);
> }
>
> static void __iomem *sched_clock_reg;
> @@ -134,10 +141,10 @@ static unsigned long imx_read_current_timer(void)
> return __raw_readl(sched_clock_reg);
> }
>
> -static int __init mxc_clocksource_init(struct clk *timer_clk)
> +static int __init mxc_clocksource_init(void)
> {
> - unsigned int c = clk_get_rate(timer_clk);
> - void __iomem *reg = timer_base + (timer_is_v2() ? V2_TCN : MX1_2_TCN);
> + unsigned int c = clk_get_rate(imxtm.clk_per);
> + void __iomem *reg = imxtm.base + (timer_is_v2() ? V2_TCN : MX1_2_TCN);
>
> imx_delay_timer.read_current_timer = &imx_read_current_timer;
> imx_delay_timer.freq = c;
> @@ -157,11 +164,11 @@ static int mx1_2_set_next_event(unsigned long evt,
> {
> unsigned long tcmp;
>
> - tcmp = __raw_readl(timer_base + MX1_2_TCN) + evt;
> + tcmp = __raw_readl(imxtm.base + MX1_2_TCN) + evt;
>
> - __raw_writel(tcmp, timer_base + MX1_2_TCMP);
> + __raw_writel(tcmp, imxtm.base + MX1_2_TCMP);
>
> - return (int)(tcmp - __raw_readl(timer_base + MX1_2_TCN)) < 0 ?
> + return (int)(tcmp - __raw_readl(imxtm.base + MX1_2_TCN)) < 0 ?
> -ETIME : 0;
> }
>
> @@ -170,12 +177,12 @@ static int v2_set_next_event(unsigned long evt, {
> unsigned long tcmp;
>
> - tcmp = __raw_readl(timer_base + V2_TCN) + evt;
> + tcmp = __raw_readl(imxtm.base + V2_TCN) + evt;
>
> - __raw_writel(tcmp, timer_base + V2_TCMP);
> + __raw_writel(tcmp, imxtm.base + V2_TCMP);
>
> return evt < 0x7fffffff &&
> - (int)(tcmp - __raw_readl(timer_base + V2_TCN)) < 0 ?
> + (int)(tcmp - __raw_readl(imxtm.base + V2_TCN)) < 0 ?
> -ETIME : 0;
> }
>
> @@ -206,11 +213,11 @@ static void mxc_set_mode(enum clock_event_mode
> mode,
> if (mode != clockevent_mode) {
> /* Set event time into far-far future */
> if (timer_is_v2())
> - __raw_writel(__raw_readl(timer_base + V2_TCN) - 3,
> - timer_base + V2_TCMP);
> + __raw_writel(__raw_readl(imxtm.base + V2_TCN) - 3,
> + imxtm.base + V2_TCMP);
> else
> - __raw_writel(__raw_readl(timer_base + MX1_2_TCN) - 3,
> - timer_base + MX1_2_TCMP);
> + __raw_writel(__raw_readl(imxtm.base + MX1_2_TCN) - 3,
> + imxtm.base + MX1_2_TCMP);
>
> /* Clear pending interrupt */
> gpt_irq_acknowledge();
> @@ -259,9 +266,9 @@ static irqreturn_t mxc_timer_interrupt(int irq, void
> *dev_id)
> uint32_t tstat;
>
> if (timer_is_v2())
> - tstat = __raw_readl(timer_base + V2_TSTAT);
> + tstat = __raw_readl(imxtm.base + V2_TSTAT);
> else
> - tstat = __raw_readl(timer_base + MX1_2_TSTAT);
> + tstat = __raw_readl(imxtm.base + MX1_2_TSTAT);
>
> gpt_irq_acknowledge();
>
> @@ -284,49 +291,48 @@ static struct clock_event_device clockevent_mxc = {
> .rating = 200,
> };
>
> -static int __init mxc_clockevent_init(struct clk *timer_clk)
> +static int __init mxc_clockevent_init(void)
> {
> if (timer_is_v2())
> clockevent_mxc.set_next_event = v2_set_next_event;
>
> clockevent_mxc.cpumask = cpumask_of(0);
> clockevents_config_and_register(&clockevent_mxc,
> - clk_get_rate(timer_clk),
> + clk_get_rate(imxtm.clk_per),
> 0xff, 0xfffffffe);
>
> return 0;
> }
>
> -static void __init _mxc_timer_init(int irq,
> - struct clk *clk_per, struct clk *clk_ipg)
> +static void __init _mxc_timer_init(void)
> {
> uint32_t tctl_val;
>
> - if (IS_ERR(clk_per)) {
> + if (IS_ERR(imxtm.clk_per)) {
> pr_err("i.MX timer: unable to get clk\n");
> return;
> }
>
> - if (!IS_ERR(clk_ipg))
> - clk_prepare_enable(clk_ipg);
> + if (!IS_ERR(imxtm.clk_ipg))
> + clk_prepare_enable(imxtm.clk_ipg);
>
> - clk_prepare_enable(clk_per);
> + clk_prepare_enable(imxtm.clk_per);
>
> /*
> * Initialise to a known state (all timers off, and timing reset)
> */
>
> - __raw_writel(0, timer_base + MXC_TCTL);
> - __raw_writel(0, timer_base + MXC_TPRER); /* see datasheet note */
> + __raw_writel(0, imxtm.base + MXC_TCTL);
> + __raw_writel(0, imxtm.base + MXC_TPRER); /* see datasheet note */
>
> if (timer_is_v2()) {
> tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN;
> - if (clk_get_rate(clk_per) == V2_TIMER_RATE_OSC_DIV8) {
> + if (clk_get_rate(imxtm.clk_per) == V2_TIMER_RATE_OSC_DIV8) {
> tctl_val |= V2_TCTL_CLK_OSC_DIV8;
> if (cpu_is_imx6dl() || cpu_is_imx6sx()) {
> /* 24 / 8 = 3 MHz */
> __raw_writel(7 << V2_TPRER_PRE24M,
> - timer_base + MXC_TPRER);
> + imxtm.base + MXC_TPRER);
> tctl_val |= V2_TCTL_24MEN;
> }
> } else {
> @@ -336,47 +342,44 @@ static void __init _mxc_timer_init(int irq,
> tctl_val = MX1_2_TCTL_FRR | MX1_2_TCTL_CLK_PCLK1 |
> MXC_TCTL_TEN;
> }
>
> - __raw_writel(tctl_val, timer_base + MXC_TCTL);
> + __raw_writel(tctl_val, imxtm.base + MXC_TCTL);
>
> /* init and register the timer to the framework */
> - mxc_clocksource_init(clk_per);
> - mxc_clockevent_init(clk_per);
> + mxc_clocksource_init();
> + mxc_clockevent_init();
>
> /* Make irqs happen */
> - setup_irq(irq, &mxc_timer_irq);
> + setup_irq(imxtm.irq, &mxc_timer_irq);
> }
>
> void __init mxc_timer_init(unsigned long pbase, int irq) {
> - struct clk *clk_per = clk_get_sys("imx-gpt.0", "per");
> - struct clk *clk_ipg = clk_get_sys("imx-gpt.0", "ipg");
> + imxtm.clk_per = clk_get_sys("imx-gpt.0", "per");
> + imxtm.clk_ipg = clk_get_sys("imx-gpt.0", "ipg");
>
> - timer_base = ioremap(pbase, SZ_4K);
> - BUG_ON(!timer_base);
> + imxtm.base = ioremap(pbase, SZ_4K);
> + BUG_ON(!imxtm.base);
>
> - _mxc_timer_init(irq, clk_per, clk_ipg);
> + _mxc_timer_init();
> }
>
> static void __init mxc_timer_init_dt(struct device_node *np) {
> - struct clk *clk_per, *clk_ipg;
> - int irq;
> -
> - if (timer_base)
> + if (imxtm.base)
> return;
>
> - timer_base = of_iomap(np, 0);
> - WARN_ON(!timer_base);
> - irq = irq_of_parse_and_map(np, 0);
> + imxtm.base = of_iomap(np, 0);
> + WARN_ON(!imxtm.base);
> + imxtm.irq = irq_of_parse_and_map(np, 0);
>
> - clk_ipg = of_clk_get_by_name(np, "ipg");
> + imxtm.clk_ipg = of_clk_get_by_name(np, "ipg");
>
> /* Try osc_per first, and fall back to per otherwise */
> - clk_per = of_clk_get_by_name(np, "osc_per");
> - if (IS_ERR(clk_per))
> - clk_per = of_clk_get_by_name(np, "per");
> + 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");
>
> - _mxc_timer_init(irq, clk_per, clk_ipg);
> + _mxc_timer_init();
> }
> CLOCKSOURCE_OF_DECLARE(mx1_timer, "fsl,imx1-gpt", mxc_timer_init_dt);
> CLOCKSOURCE_OF_DECLARE(mx25_timer, "fsl,imx25-gpt", mxc_timer_init_dt);
> --
> 1.9.1
More information about the linux-arm-kernel
mailing list