[linux-sunxi] Re: [PATCH v2 1/6] clk: sunxi-ng: Add sun4i/sun7i CCU driver

Priit Laes plaes at plaes.org
Thu Apr 20 12:59:17 PDT 2017


On Fri, Apr 07, 2017 at 03:38:05PM +0200, Maxime Ripard wrote:
> Hi Priit,
> 
> On Tue, Apr 04, 2017 at 08:09:19PM +0000, Priit Laes wrote:
> > > > +/* Not documented on A10 */
> > > > +static SUNXI_CCU_GATE(pll_periph_sata_clk, "pll-periph-sata", "pll-periph",
> > > > +		      0x028, BIT(14), 0);
> > > 
> > > The rate doesn't come from pll-periph directly, does it?
> > 
> > So it uses hosc (24MHz parent clock) instead of pll-periph?
> 
> I never looked too much at this, but it looks more like the input is
> pll-periph-sata itself.

OK, I think I have now fixed most of the issues thanks to Maxime and Chen-Yu
and I'm almost ready to send out V3.

>From my side there is only single issue remaining - how to create "sata-ext"
clock?

[snip]
static struct ccu_div pll_periph_sata_clk = {
	.enable		= BIT(14),
	.div		= _SUNXI_CCU_DIV(0, 2),
	.common		= {
		.prediv		= 6,
		.reg		= 0x028,
		.features	= CCU_FEATURE_ALL_PREDIV,
		.hw.init	= CLK_HW_INIT("pll-periph-sata",
					      "pll-periph-base",
					      &ccu_nk_ops, 0),
	},
};

static const char* const sata_parents[] = {"pll-periph-sata", "sata-ext"};
static SUNXI_CCU_MUX_WITH_GATE(sata_clk, "sata", sata_parents,
			       0x0c8, 24, 1, BIT(31), 0);
[/snip]

Should I create a fixed-clock node in the dtsi:

sata-ext: clk at 0 {
	#clock-cells = <0>;
	compatible = "fixed-clock";
	clock-frequency = <200000000>;
	clock-output-names = "sata-ext";
};

And would it also need pio definition?

Päikest,
Priit :)



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