> Instead of writing to the timer controller registers by dereferencing a
> pointer to the memory location, properly remap the memory region with a
> call to ioremap_nocache() and access the registers using writel().
>
> Signed-off-by: Thierry Reding <thierry.red...@avionic-design.de>
> ---
> arch/unicore32/kernel/pwm.c | 25 ++++++++++++++++++++++---
> 1 file changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/arch/unicore32/kernel/pwm.c b/arch/unicore32/kernel/pwm.c
> index 4615d51..410b786 100644
> --- a/arch/unicore32/kernel/pwm.c
> +++ b/arch/unicore32/kernel/pwm.c
> @@ -23,10 +23,16 @@
> #include <asm/div64.h>
> #include <mach/hardware.h>
>
> +#define PWCR 0x00
> +#define DCCR 0x04
> +#define PCR 0x08
I think old register names could be used here by some small modifications.
Please see arch/unicore32/include/mach/regs-ost.h
We can avoid ioremap and use writel/readl directly on these registers.
Guan
> +
> struct pwm_device {
> struct list_head node;
> struct platform_device *pdev;
>
> + void __iomem *base;
> +
> const char *label;
> struct clk *clk;
> int clk_enabled;
> @@ -69,9 +75,11 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int
> period_ns)
> * before writing to the registers
> */
> clk_enable(pwm->clk);
> - OST_PWMPWCR = prescale;
> - OST_PWMDCCR = pv - dc;
> - OST_PWMPCR = pv;
> +
> + writel(prescale, pwm->base + PWCR);
> + writel(pv - dc, pwm->base + DCCR);
> + writel(pv, pwm->base + PCR);
> +
> clk_disable(pwm->clk);
>
> return 0;
> @@ -190,10 +198,19 @@ static struct pwm_device *pwm_probe(struct
> platform_device *pdev,
> goto err_free_clk;
> }
>
> + pwm->base = ioremap_nocache(r->start, resource_size(r));
> + if (pwm->base == NULL) {
> + dev_err(&pdev->dev, "failed to remap memory resource\n");
> + ret = -EADDRNOTAVAIL;
> + goto err_release_mem;
> + }
> +
> __add_pwm(pwm);
> platform_set_drvdata(pdev, pwm);
> return pwm;
>
> +err_release_mem:
> + release_mem_region(r->start, resource_size(r));
> err_free_clk:
> clk_put(pwm->clk);
> err_free:
> @@ -224,6 +241,8 @@ static int __devexit pwm_remove(struct platform_device
> *pdev)
> list_del(&pwm->node);
> mutex_unlock(&pwm_lock);
>
> + iounmap(pwm->base);
> +
> r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> release_mem_region(r->start, resource_size(r));
>
> --
> 1.7.12
>
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