[PATCHv2 5/8] arm: mvebu: add common uart0 and spi0 pintcrl entries for Armada 370

Arnaud Ebalard arno at natisbad.org
Sun Nov 16 14:29:00 PST 2014


Hi,

Andrew Lunn <andrew at lunn.ch> writes:

> On Sun, Nov 16, 2014 at 06:37:33PM +0100, Arnaud Ebalard wrote:
>> 
>> pinctrl entries for uart0 using MPP0-1 and spi0 using MPP33-36 are
>> common configurations. Instead of replicating them in each .dts file,
>> put those in armada-370.dtsi file so that they can be referenced.
>> 
>> Suggested-by: Andrew Lunn <andrew at lunn.ch>
>> Signed-off-by: Arnaud Ebalard <arno at natisbad.org>
>> ---
>>  arch/arm/boot/dts/armada-370.dtsi | 11 +++++++++++
>>  1 file changed, 11 insertions(+)
>> 
>> diff --git a/arch/arm/boot/dts/armada-370.dtsi b/arch/arm/boot/dts/armada-370.dtsi
>> index 6b3c23b1e138..d9f5d59e463e 100644
>> --- a/arch/arm/boot/dts/armada-370.dtsi
>> +++ b/arch/arm/boot/dts/armada-370.dtsi
>> @@ -115,6 +115,17 @@
>>  				compatible = "marvell,mv88f6710-pinctrl";
>>  				reg = <0x18000 0x38>;
>>  
>> +				uart0_pins: uart0-pins {
>> +					marvell,pins = "mpp0", "mpp1";
>> +					marvell,function = "uart0";
>> +				};
>
> Thanks for these.
>
> We can go one stage further. kirkwood.dts has:
>
>                 uart0: serial at 12000 {
>                         compatible = "ns16550a";
>                         reg = <0x12000 0x100>;
>                         reg-shift = <2>;
>                         interrupts = <33>;
>                         clocks = <&gate_clk 7>;
>                         pinctrl-0 = <&pmx_uart0>;
>                         pinctrl-names = "default";
>                         status = "disabled";
>                 };
>
> i.e actually references them. This is safe because a board .dts file
> can override the pins if needed.
>
> We should do the same here, both for 370 and XP.

Just to be sure I understand: for uart0 and uart1, I think this can only
be done for Armada 370 (on XP, uart0/1 rx/tx are not mpp).

This only a matter of adding the following in armada-370.dtsi for uart0: 

 		 /*
		  * Default UART pinctrl setting without RTS/CTS, can
		  * be overwritten on board level.
                  */
                 uart0: serial at 12000 {
                         pinctrl-0 = <&uart0_pins>;
                         pinctrl-names = "default";
                 };

For uart1, it's not obvious because there are 6 different MPP which can
be configured to act as uart1 TXD. Same for RXD. If I remove the ones
overlapping w/ RGMII pins for GbE interfaces, which one should be
selected as default: 41/42, 55/57, 60/61?

Now, regarding armada XP, uart2 and uart3 txd/rxd MPP are 42/43 and
44/45. Best we can do is put the same as above in each specific
armada-xp-mv78XXX.dtsi file, where pinctrl node is, after adding
uart2-pins and uart3-pins. Unless I am missing something, this cannot
be done in armada-xp.dtsi.

Cheers,

a+



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