Re: [PATCH] Runtime detection of Si features

[Nishanth Menon <nm@ti.com>]

Nishanth Menon had written, on 08/13/2009 11:43 AM, the following:
> Kevin Hilman had written, on 08/13/2009 11:40 AM, the following:
>> "Pandita, Vikram" <vikram.pandita@ti.com> writes:
>>
>>>> -----Original Message-----
>>>> From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-owner@vger.kernel.org] On Behalf Of
>>>> Sent: Thursday, August 13, 2009 11:31 AM
>>>>>> Since most of the code seemed repetitive, macros
>>>>>> have been used for readability.
>>>>>>
>>>>>> Signed-off-by: Sanjeev Premi <premi@ti.com>
>>>>> I like the feature-based approach.
>>>>>
>>>>> A couple questions though.  Is there a bit/register that reports the
>>>>> collapsed powerdomains of the devices with modified PRCM?
>>>>>
>>>>> Also, how will other code query the features?  You're currently
>>>>> exporting the omap_has_*() functions, but there are no prototypes.
>>>>>
>>>>> I think I'd rather see a static inline functions in <mach/cpu.h>
>>>>> for checking features.  Comments to that end inlined below...
>>>> Wonder if we can setup some sort of infrastructure for:
>>>> a) features
>>>> b) erratas
>>>> linked to OMAP revs + even better w.r.t silicon module(SGX,I2c)
>>>> revisions since at times they are used across multiple OMAPs?
>>> We are hitting exactly this issue with I2C errata 1.153
>>> Instead of basing the errata check on cpu_is...(), 
>>> its more appropriate to base it on IP revision of I2C.
>> Shouldn't the IP revision of I2C be avaialble in an I2C revision
>> register an be used in the driver instead of cpu_is*?
> what I was proposing is a much more generic infrastructure which i2c 
> among other modules can use. Getting IP revision is already available in 
> the specific IP modules REVISION registers - we might want to 
> standardize how drivers handle revision based feature/errata set to 
> ensure that they would have an optimal way to handle the same.. just my 
> 2 cents..
> 
Thinking of this a little more:
driver's smart handling aside, having a sysfs entry to dump the features 
and erratas for each of the modules used is so much nice to have.. 
sigh.. just wondering if anyone has ideas how feasible this might be..

-- 
Regards,
Nishanth Menon