Re: [PATCH v2 4/5] clk: cygnus: add clock support for Broadcom Cygnus

Arnd Bergmann
2015-01-06T20:21:21Z

On Monday 05 January 2015 15:21:15 Ray Jui wrote:
> +static const struct iproc_clk_ctrl mipipll_clk[BCM_CYGNUS_NUM_MIPIPLL_CLKS] = {
> + [BCM_CYGNUS_MIPIPLL_CH0_UNUSED] = {
> + .channel = BCM_CYGNUS_MIPIPLL_CH0_UNUSED,
> + .enable = enable_val(0x4, 12, 6, 18),
> + .mdiv = reg_val(0x20, 0, 8),
> + },
> + [BCM_CYGNUS_MIPIPLL_CH1_LCD] = {
> + .channel = BCM_CYGNUS_MIPIPLL_CH1_LCD,
> + .enable = enable_val(0x4, 13, 7, 19),
> + .mdiv = reg_val(0x20, 10, 8),
> + },
> + [BCM_CYGNUS_MIPIPLL_CH2_UNUSED] = {
> + .channel = BCM_CYGNUS_MIPIPLL_CH2_UNUSED,
> + .enable = enable_val(0x4, 14, 8, 20),
> + .mdiv = reg_val(0x20, 20, 8),
> + },
> + [BCM_CYGNUS_MIPIPLL_CH3_UNUSED] = {
> + .channel = BCM_CYGNUS_MIPIPLL_CH3_UNUSED,
> + .enable = enable_val(0x4, 15, 9, 21),
> + .mdiv = reg_val(0x24, 0, 8),
> + },
> + [BCM_CYGNUS_MIPIPLL_CH4_UNUSED] = {
> + .channel = BCM_CYGNUS_MIPIPLL_CH4_UNUSED,
> + .enable = enable_val(0x4, 16, 10, 22),
> + .mdiv = reg_val(0x24, 10, 8),
> + },
> + [BCM_CYGNUS_MIPIPLL_CH5_UNUSED] = {
> + .channel = BCM_CYGNUS_MIPIPLL_CH5_UNUSED,
> + .enable = enable_val(0x4, 17, 11, 23),
> + .mdiv = reg_val(0x24, 20, 8),
> + },
> +};

The tables look fairly regular. Is it possible that it's common
to all iproc variants with a standard way to derive all other
values from the channel index?

> +static const struct iproc_asiu_gate asiu_gate[BCM_CYGNUS_NUM_ASIU_CLKS] = {
> + [BCM_CYGNUS_ASIU_KEYPAD_CLK] =
> + asiu_gate_val(0x0, 7),
> + [BCM_CYGNUS_ASIU_ADC_CLK] =
> + asiu_gate_val(0x0, 9),
> + [BCM_CYGNUS_ASIU_PWM_CLK] =
> + asiu_gate_val(IPROC_CLK_INVALID_OFFSET, 0),
> +};

Here I think a better binding would be to pass the gate value in the
clock specifier, rather than an artificial index. That would let
you get rid of the BCM_CYGNUS_ASIU_KEYPAD_CLK/BCM_CYGNUS_ASIU_ADC_CLK
macros.

> +static void __init cygnus_armpll_init(struct device_node *node)
> +{
> + iproc_armpll_setup(node);
> +}
> +CLK_OF_DECLARE(cygnus_armpll, "brcm,cygnus-armpll", cygnus_armpll_init);

How about moving all of these directly next to the tables, to keep
each clock controller?

> +static void __init cygnus_genpll_clk_init(struct device_node *node)
> +{
> + iproc_clk_setup(node, genpll_clk, BCM_CYGNUS_NUM_GENPLL_CLKS);
> +}

If you use ARRAY_SIZE here, you can remove the BCM_CYGNUS_NUM_GENPLL_CLKS
macro that is not useful to the DT binding.

Arnd