Re: [PATCH 2/2] omap: gpmc-nand: add ability to keep timings defined by the bootloader

[Mike Rapoport <mike@compulab.co.il>]

Vimal Singh wrote:
> On Thu, Apr 29, 2010 at 12:23 PM, Mike Rapoport <mike@compulab.co.il> wrote:
>> Vimal Singh wrote:
>>> On Wed, Apr 28, 2010 at 9:36 PM, Mike Rapoport <mike@compulab.co.il>
>>> wrote:
>>>> Signed-off-by: Mike Rapoport <mike@compulab.co.il>
>>>> +       if (gpmc_nand_data->keep_timings) {
>>>> +               gpmc_nand_detect_timings();
>>>> +               gpmc_nand_data->gpmc_t = &gpmc_default_timings;
>>>> +       }
>>>> +
>>> I guess moving this part to omap2_nand_gpmc_retime will be a good idea.
>>> As there, once we get old/default timings we can simply skip the
>>> rounding part and directly jump to setting the timings.
>> This way it would be the same as to pass 'gpmc_nand_data->gpmc_t =
>> NULL'. If I correctly understood the previous comments ([1]), the
>> problem with skipping retime is that when L3 clock changes, the gpmc
>> timings became wrong. So, if we convert old/default timings to
>> nanoseconds early during startup every time retime is called it will use
>> the timing settings in nanoseconds thus yielding proper gpmc registers
>> configuration.
> 
> OK. Then I think we can at least put __rounding__ code inside an 'if'
> case, something like:
> if (!gpmc_nand_data->keep_timings) {
> ...
> do rounding for supplied timings from board file.
> ...
> }

Sure, no problem.

>> And, if I'm not terribly mistaken retime should be called each time L3
>> frequency changes, though with current kernel it's not yet the case...
> 
> Yes. This is still left.
> 


-- 
Sincerely yours,
Mike.