On 09/09/2014 05:51 PM, Nishanth Menon wrote:
> On 09/09/2014 09:45 AM, Roger Quadros wrote:
> [...]
>>>> /* We look only at the bits of our instance. */
>>>> val &= mask;
>>>> - while ((readl(priv->raminit_ctrlreg) & mask) != val)
>>>> + while ((readl(priv->raminit_ctrlreg) & mask) != val) {
>>>> udelay(1);
>>>> + timeout++;
>>>> +
>>>> + if (timeout == 1000) {
>>>
>>> How did we come up with this number?
>>
>> wild guess ;), that it should be set in a few microseconds and the delay is
>> not too
>> large.
>>
>> Till I don't hear from hardware guys, it will remain a guess.
>>
>
> in cases like these, I suggest using emperical data as point ->
> example doing some 10,000 iterations of the operation and picking up
> the worse case number and double it.
In my tests the bit was either set immediately or never at all.
Not sure if we should increase it further.
>
> Either way, you need to document the same, else a few years down the
> line, when that number is in question, no one will know what it's
> basis was..
>
OK. I'll add a comment there.
cheers,
-roger
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
