[RFC][PATCH 03/10] arm: mxc: changes to common plat-mxc code to add support for i.MX5

Amit Kucheria amit.kucheria at canonical.com
Fri Dec 4 05:31:02 EST 2009


Some comments below:

On 09 Dec 04, Sascha Hauer wrote:
> On Thu, Dec 03, 2009 at 08:12:58PM -0700, Herring Robert-RA7055 wrote:
> > Amit,
> > 
> > I would suggest you refactor the timer code into version 1 and version 2
> > either as 2 separate files or with a timer_is_v2() function rather than
> > the mess of cpu_is_X macros it currently has. Essentially there are 2
> > versions of the timer hardware. Version 1 is found on MX1/MXL and MX21.
> > Version 2 is found on MX25, MX27, MX31, MX35, MX37, MX51, and future
> > parts. I will send you what we have done in our tree.
> Like this:
> 
> 
> commit ed6bbc59e3f6b33b48a0d5ac053220cd318ceee7
> Author: Sascha Hauer <s.hauer at pengutronix.de>
> Date:   Tue Nov 17 16:31:13 2009 +0100
> 
>     mxc timer: Add mx51 support
>     
>     Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> 
> diff --git a/arch/arm/plat-mxc/time.c b/arch/arm/plat-mxc/time.c
> index 844567e..0c45509 100644
> --- a/arch/arm/plat-mxc/time.c
> +++ b/arch/arm/plat-mxc/time.c
> @@ -57,6 +57,9 @@
>  #define MX3_TCN			0x24
>  #define MX3_TCMP		0x10
>  
> +#define timer_is_v1()	(cpu_is_mx1() || cpu_is_mx27())
                                                        ^^^^
                                      Shouldn't this be mx21 according to
				      Rob's comment?

> +#define timer_is_v2()	(cpu_is_mx3() || cpu_is_mx25() || cpu_is_mx51())

And add a cpu_is_mx27() here?

>  static struct clock_event_device clockevent_mxc;
>  static enum clock_event_mode clockevent_mode = CLOCK_EVT_MODE_UNUSED;
>  
> @@ -66,7 +69,7 @@ static inline void gpt_irq_disable(void)
>  {
>  	unsigned int tmp;
>  
> -	if (cpu_is_mx3() || cpu_is_mx25())
> +	if (timer_is_v2())
>  		__raw_writel(0, timer_base + MX3_IR);
>  	else {
>  		tmp = __raw_readl(timer_base + MXC_TCTL);
> @@ -76,7 +79,7 @@ static inline void gpt_irq_disable(void)
>  
>  static inline void gpt_irq_enable(void)
>  {
> -	if (cpu_is_mx3() || cpu_is_mx25())
> +	if (timer_is_v2())
>  		__raw_writel(1<<0, timer_base + MX3_IR);
>  	else {
>  		__raw_writel(__raw_readl(timer_base + MXC_TCTL) | MX1_2_TCTL_IRQEN,
> @@ -90,7 +93,7 @@ static void gpt_irq_acknowledge(void)
>  		__raw_writel(0, timer_base + MX1_2_TSTAT);
>  	if (cpu_is_mx2())
>  		__raw_writel(MX2_TSTAT_CAPT | MX2_TSTAT_COMP, timer_base + MX1_2_TSTAT);
> -	if (cpu_is_mx3() || cpu_is_mx25())
> +	if (timer_is_v2())
>  		__raw_writel(MX3_TSTAT_OF1, timer_base + MX3_TSTAT);
>  }
>  
> @@ -117,7 +120,7 @@ static int __init mxc_clocksource_init(struct clk *timer_clk)
>  {
>  	unsigned int c = clk_get_rate(timer_clk);
>  
> -	if (cpu_is_mx3() || cpu_is_mx25())
> +	if (timer_is_v2())
>  		clocksource_mxc.read = mx3_get_cycles;
>  
>  	clocksource_mxc.mult = clocksource_hz2mult(c,
> @@ -180,7 +183,7 @@ static void mxc_set_mode(enum clock_event_mode mode,
>  
>  	if (mode != clockevent_mode) {
>  		/* Set event time into far-far future */
> -		if (cpu_is_mx3() || cpu_is_mx25())
> +		if (timer_is_v2())
>  			__raw_writel(__raw_readl(timer_base + MX3_TCN) - 3,
>  					timer_base + MX3_TCMP);
>  		else
> @@ -233,7 +236,7 @@ static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id)
>  	struct clock_event_device *evt = &clockevent_mxc;
>  	uint32_t tstat;
>  
> -	if (cpu_is_mx3() || cpu_is_mx25())
> +	if (timer_is_v2())
>  		tstat = __raw_readl(timer_base + MX3_TSTAT);
>  	else
>  		tstat = __raw_readl(timer_base + MX1_2_TSTAT);
> @@ -264,7 +267,7 @@ static int __init mxc_clockevent_init(struct clk *timer_clk)
>  {
>  	unsigned int c = clk_get_rate(timer_clk);
>  
> -	if (cpu_is_mx3() || cpu_is_mx25())
> +	if (timer_is_v2())
>  		clockevent_mxc.set_next_event = mx3_set_next_event;
>  
>  	clockevent_mxc.mult = div_sc(c, NSEC_PER_SEC,
> @@ -296,7 +299,7 @@ void __init mxc_timer_init(struct clk *timer_clk, void __iomem *base, int irq)
>  	__raw_writel(0, timer_base + MXC_TCTL);
>  	__raw_writel(0, timer_base + MXC_TPRER); /* see datasheet note */
>  
> -	if (cpu_is_mx3() || cpu_is_mx25())
> +	if (timer_is_v2())
>  		tctl_val = MX3_TCTL_CLK_IPG | MX3_TCTL_FRR | MX3_TCTL_WAITEN | MXC_TCTL_TEN;
>  	else
>  		tctl_val = MX1_2_TCTL_FRR | MX1_2_TCTL_CLK_PCLK1 | MXC_TCTL_TEN;
> 

Otherwise these changes look good and make the code more readable.

/Amit
-- 
------------------------------------------------------------
Amit Kucheria, Finland
------------------------------------------------------------



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