[RFC 4/4] [powerpc] Implement a p1010rdb clock source.

[Kumar Gala]

On Aug 6, 2011, at 3:50 PM, Robin Holt wrote:

> On Sat, Aug 06, 2011 at 11:52:45AM -0500, Kumar Gala wrote:
>> 
>> On Aug 6, 2011, at 8:58 AM, Marc Kleine-Budde wrote:
>> 
>>> On 08/06/2011 06:05 AM, Robin Holt wrote:
>>>> flexcan driver needs the clk_get, clk_get_rate, etc functions
>>>> to work.  This patch provides the minimum functionality.
>>> 
>>> This patch has to go via the powerpc git tree. Added
>>> linuxppc-dev at lists.ozlabs.org on CC.
>>> 
>>>> Signed-off-by: Robin Holt <holt at sgi.com>
>>>> To: Marc Kleine-Budde <mkl at pengutronix.de>
>>>> To: Wolfgang Grandegger <wg at grandegger.com>
>>>> To: U Bhaskar-B22300 <B22300 at freescale.com>
>>>> Cc: socketcan-core at lists.berlios.de
>>>> Cc: netdev at vger.kernel.org
>>>> ---
>>>> arch/powerpc/platforms/85xx/p1010rdb.c |   78 ++++++++++++++++++++++++++++++++
>>>> 1 files changed, 78 insertions(+), 0 deletions(-)
>> 
>> NAK.
>> 
>> This doesn't look right at all.  We should be doing something based on the device tree node that isn't board specific.
>> 
>> I believe Bhaskar has a version of flexcan support that he's been working on cleanup up for upstream.
> 
> That version may be similar to what is in the freescale BSP which puts
> the clock functions inside flexcan.c
> 
> The powerpc arch already provides a means for individual boards to provide
> the clock functions.  I am not posting this patch here for acceptance
> for powerpc and I am sure I will get feedback there when I post to
> their mailing list.  I am posting it here only to show that the flexcan
> developers earlier assertion that this can and should be done in the arch
> tree is correct and will work for the p1010 assuming we can get changes
> into the arch/powerpc directory to implement these clk_* functions.

My point is that I don't think they should live in the arch code.  The clk_* functions you want to implement are tied more the FlexCAN IP than anything arch specific.  As such I believe they should be in the driver.

For example when FSL has a P9999 with FlexCAN on it, we should NOT have to add any arch code to support it.

- k