Patchwork [U-Boot,9/9,v2] Exynos: pwm: Use generic api to get pwm clk freq

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Submitter Minkyu Kang
Date March 28, 2013, 5:52 a.m.
Message ID <5153DAB2.9060400@samsung.com>
Download mbox | patch
Permalink /patch/231907/
State Superseded
Delegated to: Minkyu Kang
Headers show

Comments

Minkyu Kang - March 28, 2013, 5:52 a.m.
On 28/02/13 19:59, Akshay Saraswat wrote:
> Use generic api to get the pwm clock frequency
> 
> Test with command "sf probe 1:0; time sf read 40008000 0 1000".
> Try with different numbers of bytes and see that sane values are obtained
> Build and boot U-boot with this patch, backlight works properly.
> 
> Signed-off-by: Padmavathi Venna <padma.v@samsung.com>
> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com>
> ---
> Changes since v1:
>         - Restored get_pwm_clk call in case of non-exynos5 cpu.
> 
>  arch/arm/cpu/armv7/s5p-common/pwm.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/arm/cpu/armv7/s5p-common/pwm.c b/arch/arm/cpu/armv7/s5p-common/pwm.c
> index 6f401b8..f5e9a95 100644
> --- a/arch/arm/cpu/armv7/s5p-common/pwm.c
> +++ b/arch/arm/cpu/armv7/s5p-common/pwm.c
> @@ -28,6 +28,7 @@
>  #include <asm/io.h>
>  #include <asm/arch/pwm.h>
>  #include <asm/arch/clk.h>
> +#include <asm/arch/periph.h>
>  
>  int pwm_enable(int pwm_id)
>  {
> @@ -60,7 +61,10 @@ static unsigned long pwm_calc_tin(int pwm_id, unsigned long freq)
>  	unsigned long tin_parent_rate;
>  	unsigned int div;
>  
> -	tin_parent_rate = get_pwm_clk();
> +	if (cpu_is_exynos5())
> +		tin_parent_rate = clock_get_periph_rate(PERIPH_ID_PWM0);
> +	else
> +		tin_parent_rate = get_pwm_clk();
>  
>  	for (div = 2; div <= 16; div *= 2) {
>  		if ((tin_parent_rate / (div << 16)) < freq)
> @@ -165,8 +169,15 @@ int pwm_init(int pwm_id, int div, int invert)
>  		ticks_per_period = -1UL;
>  	} else {
>  		const unsigned long pwm_hz = 1000;
> -		unsigned long timer_rate_hz = get_pwm_clk() /
> -			((prescaler + 1) * (1 << div));
> +		unsigned long timer_rate_hz;
> +
> +		if (cpu_is_exynos5()) {
> +			timer_rate_hz = clock_get_periph_rate(PERIPH_ID_PWM0)
> +					/ ((prescaler + 1) * (1 << div));
> +		} else {
> +			timer_rate_hz = get_pwm_clk() /
> +				((prescaler + 1) * (1 << div));
> +		}
>  
>  		ticks_per_period = timer_rate_hz / pwm_hz;
>  	}
> 

How about this?


When we implement generic clock function for exynos4 then,
we can use clock_get_periph_rate instead of get_pwm_clk.

Thanks,
Minkyu Kang.

Patch

diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
index 956427c..a6051b0 100644
--- a/arch/arm/cpu/armv7/exynos/clock.c
+++ b/arch/arm/cpu/armv7/exynos/clock.c
@@ -1210,7 +1210,7 @@  unsigned long get_i2c_clk(void)
 unsigned long get_pwm_clk(void)
 {
        if (cpu_is_exynos5())
-               return exynos5_get_pwm_clk();
+               return clock_get_periph_rate(PERIPH_ID_PWM0);
        else {
                if (proid_is_exynos4412())
                        return exynos4x12_get_pwm_clk();