[PATCH 2/2] memory: ti-aemif: add bindings for AEMIF driver

Kumar Gala galak at kernel.crashing.org
Fri Nov 22 16:06:52 EST 2013


On Nov 20, 2013, at 1:03 PM, ivan.khoronzhuk <ivan.khoronzhuk at ti.com> wrote:

> On 11/20/2013 08:21 PM, Jean-Christophe PLAGNIOL-VILLARD wrote:
>>> +				the chip select signal.
>>> +				Minimum value is 1 (0 treated as 1).
>>> +
>>> +- ti,cs-wsetup:		write setup width, ns
>>> +				Time between the beginning of a memory cycle
>>> +				and the activation of write strobe.
>>> +				Minimum value is 1 (0 treated as 1).
>>> +
>>> +- ti,cs-wstrobe:	write strobe width, ns
>>> +				Time between the activation and deactivation of
>>> +				the write strobe.
>>> +				Minimum value is 1 (0 treated as 1).
>>> +
>>> +- ti,cs-whold:		write hold width, ns
>>> +				Time between the deactivation of the write
>>> +				strobe and the end of the cycle (which may be
>>> +				either an address change or the deactivation of
>>> +				the chip select signal.
>>> +				Minimum value is 1 (0 treated as 1).
>>> +
>>> +If any of the above parameters are absent, current parameter value will be taken
>>> +from the corresponding HW reg.
>>> +
>>> +The name for cs node must be in format csN, where N is the cs number.
>> 
>> this is wired we should use reg instead to represent the cs as done for SPI
>> or a an other property
>> 
>> Best Regards,
>> J.
>> 
> 
> Ok, I will add new property cs-chipselect like following :
> 
> ti,cs-chipselect:	number of chipselect. Indicates on the
> 			aemif driver which chipselect is used
> 			for accessing the memory.
> 			For compatibles "ti,davinci-aemif" and 
> 			"ti,keystone-aemif" it can be in range [0-3].
> 			For compatible "ti,omap-L138-aemif" range is [2-5].
> 
> Is it OK?

Why do you need this? As it was mentioned just use reg:

So you’d have something like:

memory-controller at 21000A00 {
	…
	nand:cs2 at 2 {
		reg = <2 0 0>;
		ranges;
		...

	}:
};

However, I’m confused by the example in which you have:

+		nand at 0,0x8000000 {
+			compatible = "ti,davinci-nand";
+			reg = <0 0x8000000 0x4000000
+			       1 0x0000000 0x0000100>;
+
+			.. see davinci-nand.txt
+		};

What chipselects is this on 0 & 1?

- k
			
> 
> -- 
> Regards,
> Ivan Khoronzhuk
> --
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