Re: [PATCH v2 1/1] net/macb: add TX multiqueue support for gem

[Cyrille Pitchen]

Le 12/12/2014 10:45, David Laight a écrit :
> From: Thomas Petazzoni
>> On Thu, 11 Dec 2014 11:16:51 +0100, Cyrille Pitchen wrote:
>>
>>> +#define GEM_ISR1				0x0400
>>> +#define GEM_ISR2				0x0404
>>> +#define GEM_ISR3				0x0408
>>> +#define GEM_ISR4				0x040c
>>> +#define GEM_ISR5				0x0410
>>> +#define GEM_ISR6				0x0414
>>> +#define GEM_ISR7				0x0418
>>
>> What about doing instead:
>>
>> #define GEM_ISR(q)				((q) == 0 ? MACB_ISR : 0x400 + (q) << 2)
>>
>> And ditto for all other registers, which will save a lot of boring repeated code.
> 
> It will probably add a lot of object code and, depending on how often
> the registers are accesses, might have performance impact.
> 
> Having:
> #define GEM_ISR(n) (0x400 + (n) << 4)
> will save source code.
> 
> 	David
> 
> 
> 
So you suggest that we keep the unsigned int fields ISR, IMR, IER, IDR, TBQP in
the struct macb_queue and initialize them once for all in macb_probe() like
patch v2 does but only replace the GEM_ISR1 .. GEM_ISR7 defines by GEM_ISR(n)
in macb.h?

This way there would be to test at run time and we can handle the special
register mapping of queue0.

Is it what you meant?

Regards,

Cyrille
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/