[PATCH] phy: dp83867: add dp83867_{read,write}_mmd helpers

[Rasmus Villemoes]

On 19/05/2022 16.38, Vladimir Oltean wrote:
> Hi Rasmus,
> 
> On Tue, May 17, 2022 at 04:27:06PM +0200, Rasmus Villemoes wrote:
>> Since the phy_{read,write}_mmd functions are static inlines using
>> other static inline functions, they cause code using them to explode.
>>
>> Defining local wrappers cuts the size of the generated code by 50%:
>>
>> $ size drivers/net/phy/dp83867.o.{before,after}
>>    text    data     bss     dec     hex filename
>>    4873     112       0    4985    1379 drivers/net/phy/dp83867.o.before
>>    2413     112       0    2525     9dd drivers/net/phy/dp83867.o.after
>>
>> Of course, most of that improvement could also be had by making the
>> phy_*_mmd functions out-of-line, and they probably should be, but this
   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>> still has the advantage of avoiding passing the DP83867_DEVADDR
>> argument at all call sites, which allows lines to be unwrapped (and
>> probably also gives a little .text reduction by itself).
>>
>> Signed-off-by: Rasmus Villemoes <rasmus.villemoes at prevas.dk>
>> ---
> 
> Have you considered making phy_read_mmd() and phy_write_mmd() non-inline?
> There are few users, but it looks like they would all benefit from this.

Yes, I wrote precisely that in the commit message. But the problem with
that is finding some TU to put them in which is guaranteed to be built
and included by all current users. This localized change gives just
about the same benefit in .text, plus the line unwrapping. And nothing
prevents somebody later from figuring out a proper place to put
out-of-line versions of these phy_*_mmd functions.

Rasmus