Re: [PATCH] pinctrl: sunxi: Add H3 R_PIO controller support

From: Krzysztof Adamski
Date: Tue Feb 02 2016 - 07:10:52 EST


On Tue, Feb 02, 2016 at 10:24:51AM +0100, Krzysztof Adamski wrote:
On Tue, Feb 02, 2016 at 02:25:18PM +0800, Chen-Yu Tsai wrote:
On Mon, Feb 1, 2016 at 6:12 PM, Krzysztof Adamski <k@xxxxxxxx> wrote:
- reg: Should contain the register physical address and length for the
diff --git a/arch/arm/boot/dts/sun8i-h3.dtsi
b/arch/arm/boot/dts/sun8i-h3.dtsi
index 1524130e..745f64c 100644
--- a/arch/arm/boot/dts/sun8i-h3.dtsi
+++ b/arch/arm/boot/dts/sun8i-h3.dtsi
@@ -493,5 +493,17 @@
interrupts = <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>,
<GIC_SPI 41 IRQ_TYPE_LEVEL_HIGH>;
};
+
+ r_pio: pinctrl@01f02c00 {
+ compatible = "allwinner,sun8i-h3-r-pinctrl";
+ reg = <0x01f02c00 0x400>;
+ interrupts = <GIC_SPI 45 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&bus_gates 69>;

This is probably wrong. According to other SoCs all R_ block peripherals
have clock gates and reset controls in the PRCM.

This is problematic. I can find information about reset and gates control for
this peripheral on other SoCs user manuals but there is nothing about it in H3
User Manual
(https://www.dropbox.com/s/nkr9slo1o9x6i1z/Allwinner_H3_Datasheet_V1.1.pdf?dl=0).

Similarly, while I think I can find r_pio clock setup for A33:
https://github.com/allwinner-zh/linux-3.4-sunxi/blob/master/drivers/clk/sunxi/clk-sun8iw5.c

I can't find it for H3, though:
https://github.com/allwinner-zh/linux-3.4-sunxi/blob/master/drivers/clk/sunxi/clk-sun8iw7.c

Well, apart from this strange snippet:

// binder r-pio CPUS_APB0_GATE to pio-clk's gate-reset-register
clk = clk_get(NULL,"pio");
if(!clk || IS_ERR(clk))
printk("Error not get clk pio\n");
else
{
struct clk_hw *hw = __clk_get_hw(clk);
struct sunxi_clk_periph *periph = to_clk_periph(hw);
struct sunxi_clk_periph_gate *gate = &periph->gate;
gate->reset = sunxi_clk_cpus_base+CPUS_APB0_GATE ;
gate->rst_shift = 0;
clk_put(clk);
}


Which I have to admit I don't fully understand. This seems to be setting reset
line for first pio, not for r_pio - something we don't have right now. Or am I
wrong here?

I'm new to Allwinner SoCs, any help from veterans?

Also, if that proves anything, I did test this code on OrangePi PC and PL ports
works so their clock is enabled, for sure.

I did some tests and indeed, when I disabled PIO clock (bus_gates 69), R_PIO was still working while PIO did not. So I tryied to take the same address other SoCs are using (0x01f01468 - CPUS_APB0 register) and clearing 1st bit (which is enabled by default) disables R_PIO. So, well, it seems that this works the same as on other sunxi SoCs. I'll try doing proper change.

Best regards,
Krzysztof Adamski