Re: [RESPIN 5/6] dt-bindings: EXYNOS: Describe SROMc configuration

From: pankaj.dubey
Date: Fri Mar 04 2016 - 23:46:17 EST


Hi,

On Wednesday 02 March 2016 11:27 PM, Rob Herring wrote:
> On Thu, Feb 25, 2016 at 02:03:41PM +0530, Pankaj Dubey wrote:
>> From: Pavel Fedin <p.fedin@xxxxxxxxxxx>
>>
>> Add documentation for new subnode properties, allowing bank configuration.
>> Based on u-boot implementation, but heavily reworked.
>>
>> Also, fix size of SROMc mapping in the example.
>
> Fix it in the previous patch.

OK.

>
>> CC: devicetree@xxxxxxxxxxxxxxx
>> Signed-off-by: Pavel Fedin <p.fedin@xxxxxxxxxxx>
>> Signed-off-by: Pankaj Dubey <pankaj.dubey@xxxxxxxxxxx>
>> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
>> Acked-by: Rob Herring <robh@xxxxxxxxxx>
>> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
>> ---
>> .../bindings/memory-controllers/exynos-srom.txt | 73 +++++++++++++++++++++-
>> 1 file changed, 71 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/memory-controllers/exynos-srom.txt b/Documentation/devicetree/bindings/memory-controllers/exynos-srom.txt
>> index 33886d5..e5c18df 100644
>> --- a/Documentation/devicetree/bindings/memory-controllers/exynos-srom.txt
>> +++ b/Documentation/devicetree/bindings/memory-controllers/exynos-srom.txt
>> @@ -5,8 +5,77 @@ Required properties:
>>
>> - reg: offset and length of the register set
>>
>> -Example:
>> +Optional properties:
>> +The SROM controller can be used to attach external peripherals. In this case
>> +extra properties, describing the bus behind it, should be specified as below:
>> +
>> +- #address-cells: Must be set to 2 to allow device address translation.
>> + Address is specified as (bank#, offset).
>> +
>> +- #size-cells: Must be set to 1 to allow device size passing
>> +
>> +- ranges: Must be set up to reflect the memory layout with four integer values
>> + per bank:
>> + <bank-number> 0 <parent address of bank> <size>
>> +
>> +Sub-nodes:
>> +The actual device nodes should be added as subnodes to the SROMc node. These
>> +subnodes, except regular device specification, should contain the following
>
> s/except/in addition to/
>

OK. Will update this description as suggested.

>> +properties, describing configuration of the relevant SROM bank:
>> +
>> +Required properties:
>> +- reg: bank number, base address (relative to start of the bank) and size of
>> + the memory mapped for the device. Note that base address will be
>> + typically 0 as this is the start of the bank.
>> +
>> +- samsung,srom-timing : array of 6 integers, specifying bank timings in the
>> + following order: Tacp, Tcah, Tcoh, Tacc, Tcos, Tacs.
>> + Each value is specified in cycles and has the following
>> + meaning and valid range:
>> + Tacp : Page mode access cycle at Page mode (0 - 15)
>> + Tcah : Address holding time after CSn (0 - 15)
>> + Tcoh : Chip selection hold on OEn (0 - 15)
>> + Tacc : Access cycle (0 - 31, the actual time is N + 1)
>> + Tcos : Chip selection set-up before OEn (0 - 15)
>> + Tacs : Address set-up before CSn (0 - 15)
>> +
>> +Optional properties:
>> +- reg-io-width : data width in bytes (1 or 2). If omitted, default of 1 is used.
>> +
>> +- samsung,srom-page-mode : page mode configuration for the bank:
>> + 0 - normal (one data)
>> + 1 - four data
>> + If omitted, default of 0 is used.
>
> Make this a bool instead.
>

I do not have strong objections to change this, but I can see doing so
will increase two or three lines in driver, as such this property is not
being used as bool in driver.


Sorry to say this but I do not understand why these comments are coming
now? Whereas you had given your "Acked-by" to the same patch when it was
posted previously by Pavel and we were keeping this driver under
"drivers/soc/samsung". Is it just because we are moving to
"drivers/memory" and it needs to be consistent with other memory
controller drivers?

Thanks,
Pankaj Dubey
> Rob
>
>