[PATCH v2 2/7] ARM: mmp: parse timer configuration from DT
Grant Likely
grant.likely at secretlab.ca
Fri Jul 29 12:40:45 EDT 2011
On Thu, Jul 28, 2011 at 02:41:28PM +0800, Haojian Zhuang wrote:
> Parse timer configuration from DT. Now we can merge pxa910_timer and
> mmp2_timer into mmp_timer. Since most configuration between these two
> timers are same. The difference is recorded in DT.
>
> Signed-off-by: Haojian Zhuang <haojian.zhuang at marvell.com>
> ---
> .../devicetree/bindings/arm/marvell/timer.txt | 24 +++++++++
> arch/arm/mach-mmp/common.h | 2 +
> arch/arm/mach-mmp/time.c | 50 +++++++++++++++++++-
> 3 files changed, 75 insertions(+), 1 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/arm/marvell/timer.txt
>
> diff --git a/Documentation/devicetree/bindings/arm/marvell/timer.txt b/Documentation/devicetree/bindings/arm/marvell/timer.txt
> new file mode 100644
> index 0000000..24a6f97
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/marvell/timer.txt
> @@ -0,0 +1,24 @@
> +* Timer Controller Binding for ARCH-MMP
> +
> +This binding specifies what properties must be available in device tree
> +representation of an ARCH-MMP compliant timer controller.
> +
> +Required properties:
> +
> + - compatible: Specifies the compatibility list of the timer controller.
> + The type shall be <string> and the value shall be
> + "mrvl,pxa168-timer".
> +
> + - mrvl,clk-conf: Specifies the address and value of timer
> + configuration register.
> + The type shall be <prop-encoded-array>. The first value indicates
> + the physical address of timer configuration register. The second
> + value indicates data should be written to timer configuration
> + register.
> +
> +* Example
> +
> + mmp_timer: {
> + compatible = "mrvl,pxa168-timer";
> + mrvl,clk-conf = <0xd4000034 0x33>;
> + };
> diff --git a/arch/arm/mach-mmp/common.h b/arch/arm/mach-mmp/common.h
> index 1c563c2..890c664 100644
> --- a/arch/arm/mach-mmp/common.h
> +++ b/arch/arm/mach-mmp/common.h
> @@ -2,6 +2,8 @@
>
> struct sys_timer;
>
> +extern struct sys_timer mmp_timer;
> +
> extern void timer_init(int irq);
>
> extern void __init icu_init_irq(void);
> diff --git a/arch/arm/mach-mmp/time.c b/arch/arm/mach-mmp/time.c
> index 99833b9..5a90b27 100644
> --- a/arch/arm/mach-mmp/time.c
> +++ b/arch/arm/mach-mmp/time.c
> @@ -25,6 +25,8 @@
>
> #include <linux/io.h>
> #include <linux/irq.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
> #include <linux/sched.h>
>
> #include <asm/sched_clock.h>
> @@ -150,7 +152,7 @@ static void __init timer_config(void)
>
> __raw_writel(cer & ~0x1, TIMERS_VIRT_BASE + TMR_CER); /* disable */
>
> - ccr &= (cpu_is_mmp2()) ? TMR_CCR_CS_0(0) : TMR_CCR_CS_0(3);
> + ccr &= TMR_CCR_CS_0(0);
> __raw_writel(ccr, TIMERS_VIRT_BASE + TMR_CCR);
>
> /* free-running mode */
> @@ -187,3 +189,49 @@ void __init timer_init(int irq)
> clocksource_register_hz(&cksrc, CLOCK_TICK_RATE);
> clockevents_register_device(&ckevt);
> }
> +
> +#ifdef CONFIG_OF
> +static void __init mmp_timer_init(void)
> +{
> + struct device_node *np;
> + const __be32 *clk_offs;
> + void __iomem *conf;
> + unsigned int addr = 0, offs = 0;
> + int size, irq;
> +
> + np = of_find_compatible_node(NULL, NULL, "mrvl,pxa168-timer");
> +
> + BUG_ON(!np);
> +
> + of_node_get(np);
> + irq = irq_of_parse_and_map(np, 0);
> +
> + clk_offs = of_get_property(np, "mrvl,clk-conf", &size);
> + if ((clk_offs == NULL) || (size != sizeof(int) * 2)) {
sizeof(u32)
I would recommend using of_property_read_u32_array() which does the
sanity checking for you.
> + pr_warn("mmp-timer: mrvl,clk-conf property is wrong\n");
> + goto out;
> + }
> + addr = be32_to_cpu(*clk_offs) & PAGE_MASK;
> + offs = be32_to_cpu(*clk_offs) - addr;
> + conf = ioremap(addr, PAGE_SIZE);
base addresses should be in a 'reg' property. I would put the
register region into a 'reg' tuple so that of_iomap() works, and then
encode just the offset/config-value pair into mrvl,clk-conf.
> + if (conf == NULL) {
> + pr_warn("mmp-timer: failed on mapping 0x%x\n", (uint32_t)conf);
> + goto out;
> + }
> + /* reset and configure */
> + __raw_writel(APBC_APBCLK | APBC_RST, conf + offs);
> + __raw_writel(be32_to_cpu(*++clk_offs), conf + offs);
> + __raw_readl(conf + offs);
> + iounmap(conf);
> +
> + timer_init(irq);
> + return;
> +out:
> + of_node_put(np);
> + return;
> +}
> +
> +struct sys_timer mmp_timer = {
> + .init = mmp_timer_init,
> +};
> +#endif
> --
> 1.5.6.5
>
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