[1/9] ARM: imx: move timer resources into a structure

From: Shawn Guo <shawn.guo@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@linaro.org>
---
 arch/arm/mach-imx/time.c | 119 ++++++++++++++++++++++++-----------------------
 1 file changed, 61 insertions(+), 58 deletions(-)

On 05/15/2015 10:11 AM, shawnguo@kernel.org wrote:
> From: Shawn Guo <shawn.guo@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@linaro.org>

I would be nice to embed the clockevent_mxc variable in the structure as 
well and use container_of to retrieve the structure from the struct 
clockevent.

The struct clockevent can be the unified parameter across the different 
functions.

Refer to drivers/clocksource/rockchip_timer.c as an example.

> ---
>   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;
>
>   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);
>