Re: [PATCH v2 1/3] ARM: DRA7: hwmod: Add OCP2SCP3 module

[Roger Quadros <rogerq@ti.com>]

Paul,

On 07/06/2014 03:23 AM, Paul Walmsley wrote:
> Hi
> 
> On Fri, 4 Jul 2014, Roger Quadros wrote:
> 
>> On 07/03/2014 10:48 PM, Paul Walmsley wrote:
>>> On Thu, 3 Jul 2014, Roger Quadros wrote:
>>>
>>>> This module is needed for the SATA and PCIe PHYs.
>>>>
>>>> Signed-off-by: Roger Quadros <rogerq@ti.com>
>>>> Reviewed-by: Rajendra Nayak <rnayak@ti.com>
>>>> Tested-by: Sekhar Nori <nsekhar@ti.com>>
>>>
>>> This looks like adding support for a new device, so, after 
>>> discussing with Tony, queuing for v3.17.
>>
>> We should treat it as missing device (bug) rather than new device 
>> (feature) as the corresponding device tree node is already present.
>> Without this patch we get the following message in kernel boot log
>>
>> [    0.261680] platform 4a090000.ocp2scp: Cannot lookup hwmod 'ocp2scp3'
>>
>> I would consider this patch as a fix rather than a new feature.
> 
> Just to make sure I'm correctly applying the rules for sequencing -rc 
> patches vs. merge window patches, could you please confirm my 
> understanding of the situation:
> 
> 1. The OCP2SCP3 device (and the devices that rely on it) never worked on 
> DRA7xx in earlier kernels
> 
> 2. Even with this support added, neither SATA nor PCIe will work in 3.16 
> on DRA7xx (SATA for unknown reasons, PCIe because the patches are targeted 
> for 3.17).

The reason for SATA not working has been identified and the fix is posted here
https://lkml.org/lkml/2014/7/4/166
So this hwmod patch is the only missing piece why SATA won't work on 3.16.

> 
> 3. The warning doesn't prevent the machine from booting and does not 
> impair any previously working functionality
> 
> 4. There are other DRA7xx warning messages on boot in 3.16-rc: for 
> example, http://paste.ubuntu.com/7701601/ lists:
> 
> [    0.009931] omap_hwmod: l3_main_2 using broken dt data from ocp
> 
> ...
> 
> [    0.291802] platform 4e000000.dmm: Cannot lookup hwmod 'dmm'
> 
> 
> Are these four statements correct?

Yes for 1,3 and 4.

> 
> If so, is there some other reason why we should rush this in for 3.16-rc?  
> Put differently: how can we justify adding this device in 3.16-rc rather 
> than 3.17 to Linus Torvalds?

Nothing else that I can think of apart from SATA not working on 3.16.

cheers,
-roger