[U-Boot] [PATCH 1/2] ARM: dts: zynq: Update dts for Z-turn board

[Anton Gerasimov]

Hi Alexander,


>>   		device_type = "memory";
>>   		reg = <0x0 0x40000000>;
>>   	};
>>   
>>   	chosen {
>> -		stdout-path = "serial0:115200n8";
> Nack. By default graphical output is quite unusable on this board, so we
> want to output to serial.
>
> If your Linux submitted device tree doesn't contain this part, please
> fix it there.
>
>> +		bootargs = "console=ttyPS0,115200 earlyprintk root=/dev/mmcblk0p2 rootwait";
> This is even worse. Please don't prepopulate any bootargs, otherwise
> people may end up assuming that they're actually getting used.

The older one is much cleaner I agree, thank you. I'll just need to test 
with both u-boot and linux.

>>   	};
>>   
>>   	gpio-leds {
>>   		compatible = "gpio-leds";
>> -		led_r {
>> -			label = "led_r";
>> -			gpios = <&gpio0 0x72 0x1>;
>> -			default-state = "on";
>> -			linux,default-trigger = "heartbeat";
>> -		};
>> -
>> -		led_g {
>> -			label = "led_g";
>> -			gpios = <&gpio0 0x73 0x1>;
>> -			default-state = "on";
>> -			linux,default-trigger = "heartbeat";
>> -		};
>> -
>> -		led_b {
>> -			label = "led_b";
>> -			gpios = <&gpio0 0x74 0x1>;
>> -			default-state = "on";
>> -			linux,default-trigger = "heartbeat";
>> -		};
> Why remove them? They're hard wired on the board, no?
No this RGB LED is connected to PL, that's for sure.

>>   	ps-clk-frequency = <33333333>;
>> -	fclk-enable = <0xf>;
> Why?

> IIRC on my Z-Turn, I had to take a PL clock back into the PS as AXI
> reference clock. See "Connect clocks" here:
>
>
>
>    https://wiki.hackerspace.pl/projects:zturn-hackers:helloworld
>
>
>
> So we need to have the PL clock enabled, no? Or is that only needed for
> PL AXI peripherals?
>

As far as I understand M_AXI_GPn connects AXI slaves implemented on PL 
to AXI and S_AXI_HPn provides access for AXI slaves in PS to PL slaves. 
So both involve PL and can be disconnected if PL is not clocked.

>>   };
>>   
>>   &qspi {
>> @@ -152,8 +114,8 @@
>>   		reg = <0x49>;
>>   	};
>>   
>> -	adxl345 at 53 {
>> -		compatible = "adi,adxl34x", "adxl34x";
>> +	accelerometer at 53 {
>> +		compatible = "adi,adxl345", "adxl345";
> You can't just remove compatibles. Device trees are supposed to be
> compatible with whatever used them before someone thought they want to
> prettify them, so in this case you'd have to add the concrete names in
> the list before the abstract ones:
>
>    compatible = "adi,adxl345", "adxl345", "adi,adxl34x", "adxl34x";
Yes sorry, I didn't realize that Linux kernel had both.

Best,
Anton