[PATCH 1/5] cpufreq-pxa3xx: use HSIO 312MHz on the pxa310

[Eric Miao]

On Mon, Jul 12, 2010 at 5:13 PM, Igor Grinberg <grinberg at compulab.co.il> wrote:
>
>
> On 07/12/10 11:37, pieterg wrote:
>> On Sunday 11 July 2010 09:14:22 Igor Grinberg wrote:
>>
>>> On 07/09/10 11:31, pieterg wrote:
>>>
>>>> On Friday 09 July 2010 10:02:16 Eric Miao wrote:
>>>>
>>>>> What's wrong with 208MHz HSS on PXA310?
>>>>>
>>>> I haven't done any benchmarking, but Marvell found it worth to
>>>> introduce 312MHz for the pxa310. (I assume it might have something to
>>>> do with the video accelerator, which is unique to the pxa310).
>>>>
>>>> And to me it makes sense to use the highest supported speeds in the top
>>>> cpufreq entry.
>>>>
>>> According to Marvell's PXA3xx Specification Update document
>>> (page 68 - SCr#3), the above is correct starting from silicon revision
>>> A2. What about earlier revisions? Shouldn't we support all of them?
>>>
>> OK, I missed that. In that case we should leave this one out.
>>
>
> If you really want this to go, you can check the cpu stepping (cpuid
> register)
> and fixup the table accordingly. Something like:
>
> if (cpu_is_pxa310())
>        ret = setup_freqs_table(policy, (read_cpuid_id() & 0xf) ?
>
> ARRAY_AND_SIZE(pxa310_freqs) :
>
> ARRAY_AND_SIZE(pxa300_freqs));
>
> but I don't know if Eric will like it ;)
>

Nah, I was thinking of introducing a cpu_is_pxa310_a2() or something,
but that's really hard to make generic, since for this case, we'd
have to use cpu_is_pxa310_a2_or_above(), which is #!$!%!@#$

So to put it simple, I think a command line parameter would make
more sense in this case. e.g. pxa310_use_312mhz.

>> Rgds, Pieter
>>
>>
>
> --
> Regards,
> Igor.
>
>