[PATCH V3 12/18] ARM: OMAP2+: Add additional GPMC timing parameters

Jon Hunter jon-hunter at ti.com
Mon Mar 18 11:59:48 EDT 2013


On 03/18/2013 09:32 AM, Jon Hunter wrote:
> 
> On 03/18/2013 09:07 AM, Rob Herring wrote:
>> On 03/15/2013 10:21 AM, Jon Hunter wrote:
>>> Some of the GPMC timings parameters are currently missing from the GPMC
>>> device-tree binding. Add these parameters to the binding documentation
>>> as well as code to read them.
>>>
>>> The existing code in gpmc_read_timings_dt() is checking the value of
>>> of_property_read_u32() and only is successful storing the value read
>>> in the gpmc_timings structure. Checking the return value in this case
>>> is not necessary and we can simply read the value, if present, and
>>> store directly in the gpmc_timings structure. Therefore, simplify the
>>> code by removing these checks.
>>>
>>> The comment in the gpmc_read_timings_dt() function, "only for OMAP3430"
>>> is also incorrect as it is applicable to all OMAP3+ devices. So correct
>>> this too.
>>>
>>> Signed-off-by: Jon Hunter <jon-hunter at ti.com>
>>> ---
>>>  Documentation/devicetree/bindings/bus/ti-gpmc.txt |   25 +++++-
>>>  arch/arm/mach-omap2/gpmc.c                        |   93 ++++++++++-----------
>>>  2 files changed, 66 insertions(+), 52 deletions(-)
>>>
>>> diff --git a/Documentation/devicetree/bindings/bus/ti-gpmc.txt b/Documentation/devicetree/bindings/bus/ti-gpmc.txt
>>> index 6fde1cf..a63bd93 100644
>>> --- a/Documentation/devicetree/bindings/bus/ti-gpmc.txt
>>> +++ b/Documentation/devicetree/bindings/bus/ti-gpmc.txt
>>> @@ -56,10 +56,27 @@ Timing properties for child nodes. All are optional and default to 0.
>>>   - gpmc,oe-off:		Deassertion time
>>>  
>>>   Access time and cycle time timings corresponding to GPMC_CONFIG5:
>>> - - gpmc,page-burst-access: Multiple access word delay
>>> - - gpmc,access:		Start-cycle to first data valid delay
>>> - - gpmc,rd-cycle:	Total read cycle time
>>> - - gpmc,wr-cycle:	Total write cycle time
>>> + - gpmc,page-burst-access: 	Multiple access word delay
>>> + - gpmc,access:			Start-cycle to first data valid delay
>>> + - gpmc,rd-cycle:		Total read cycle time
>>> + - gpmc,wr-cycle:		Total write cycle time
>>> + - gpmc,bus-turnaround:		Turn-around time between successive accesses
>>> + - gpmc,cycle2cycle-delay:	Delay between chip-select pulses
>>> + - gpmc,clk-activation: 	GPMC clock activation time
>>> + - gpmc,wait-monitoring:	Start of wait monitoring with regard to valid
>>> +				data
>>
>> What units are these in? If in nanoseconds, can you append "-ns"
> 
> These are cycles. I can update the comment to reflect that.

Sorry these are nanoseconds. I will update the properties to reflect that.

Jon



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