On Fri, Nov 28, 2014 at 12:51 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> On Friday 28 November 2014 00:44:07 Chanwoo Choi wrote:
>> >
>> >> +#define bus_div_clks(num) \
>> >> +static struct samsung_div_clock bus##num_div_clks[] __initdata = { \
>> >> + /* DIV_BUS */ \
>> >> + DIV(CLK_DIV_PCLK_BUS##num_133, "div_pclk_bus"#num"_133", \
>> >> + "aclk_bus"#num"_400", DIV_BUS##num, 0, 3), \
>> >> +}; \
>> >
>> > To illustrate my point further: CLK_DIV_PCLK_BUS0/1/2 are all the
>> > same, and so are DIV_BUS0/1/2, so you should not need to duplicate
>> > the definitions at all but just call them 'CLK_DIV_PCLK_BUS'
>> > and 'DIV_BUS'.
>>
>> CLK_DIV_PCLK_BUS0/1/2 is not all the same.
>> Each CLK_DIV_PCLK_BUS0/1/2 must need the unique clock number.
>> Because some device may need some clocks by using unique clock number.
>
> This is from your original patch:
>
> +/* CMU_BUS0 */
> +#define CLK_DIV_PCLK_BUS0_133 1
> +
> +#define CLK_ACLK_AHB2APB_BUS0P 2
> +#define CLK_ACLK_BUS0NP_133 3
> +#define CLK_ACLK_BUS0ND_400 4
> +#define CLK_PCLK_BUS0SRVND_133 5
> +#define CLK_PCLK_PMU_BUS0 6
> +#define CLK_PCLK_SYSREG_BUS0 7
> +
> +#define BUS0_NR_CLK 8
> +
> +/* CMU_BUS1 */
> +#define CLK_DIV_PCLK_BUS1_133 1
> +
> +#define CLK_ACLK_AHB2APB_BUS1P 2
> +#define CLK_ACLK_BUS1NP_133 3
> +#define CLK_ACLK_BUS1ND_400 4
> +#define CLK_PCLK_BUS1SRVND_133 5
> +#define CLK_PCLK_PMU_BUS1 6
> +#define CLK_PCLK_SYSREG_BUS1 7
> +
> +#define BUS1_NR_CLK 8
> +
> +/* CMU_BUS2 */
> +#define CLK_MOUT_ACLK_BUS2_400_USER 1
> +
> +#define CLK_DIV_PCLK_BUS2_133 2
> +
> +#define CLK_ACLK_AHB2APB_BUS2P 3
> +#define CLK_ACLK_BUS2NP_133 4
> +#define CLK_ACLK_BUS2BEND_400 5
> +#define CLK_ACLK_BUS2RTND_400 6
> +#define CLK_PCLK_BUS2SRVND_133 7
> +#define CLK_PCLK_PMU_BUS2 8
> +#define CLK_PCLK_SYSREG_BUS2 9
> +
> +#define BUS2_NR_CLK 10
>
>
> The numbers are arbitrarily assigned, but for bus0 and bus1,
> they are all identical, while bus2 uses a lightly different
> numbering, which you could easily change, e.g. by using the
> numbers you have for bus2 on bus0 and bus1 as well.
OK, I'll remove duplicate clock number due to the same on other clock domain.
If use only CLK_DIV_PCLK_BUS instead of CLK_DIV_PCLK_BUS0/1/2,
I think I have to use three compatible string for each CMU_BUSx domain
as following:.
clocks = <&cmu_bus0 CLK_DIV_PCLK_BUS>;
clocks = <&cmu_bus1 CLK_DIV_PCLK_BUS>;
clocks = <&cmu_bus2 CLK_DIV_PCLK_BUS>;
>
> + * Register offset definitions for CMU_BUS0
> + */
> +#define DIV_BUS0 0x0600
> +#define DIV_STAT_BUS0 0x0700
> +#define ENABLE_ACLK_BUS0 0x0800
> +#define ENABLE_PCLK_BUS0 0x0900
> +#define ENABLE_IP_BUS0 0x0b00
> +#define ENABLE_IP_BUS1 0x0b04
> +
>
> +/*
> + * Register offset definitions for CMU_BUS1
> + */
> +#define DIV_BUS1 0x0600
> +#define DIV_STAT_BUS1 0x0700
> +#define ENABLE_ACLK_BUS1 0x0800
> +#define ENABLE_PCLK_BUS1 0x0900
> +#define ENABLE_IP_BUS10 0x0b00
> +#define ENABLE_IP_BUS11 0x0b04
>
> +/*
> + * Register offset definitions for CMU_BUS2
> + */
> +#define MUX_SEL_BUS2 0x0200
> +#define MUX_ENABLE_BUS2 0x0300
> +#define MUX_STAT_BUS2 0x0400
> +#define DIV_BUS2 0x0600
> +#define DIV_STAT_BUS2 0x0700
> +#define ENABLE_ACLK_BUS2 0x0800
> +#define ENABLE_PCLK_BUS2 0x0900
> +#define ENABLE_IP_BUS20 0x0b00
> +#define ENABLE_IP_BUS21 0x0b04
>
> More importantly, the register offsets are all identical, except that
> bus2 has the additional MUX_SEL and MUX_ENABLE definitions. It's very
> obvious that this is the same hardware block in multiple instances.
You're right. I'll remove duplicate offset definition.
Best Regards,
Chanwoo Choi
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