Adding new media types to if_media.h

Hans Petter Selasky hps at selasky.org
Thu Feb 26 14:34:38 UTC 2015


On 02/26/15 15:21, Mike Karels wrote:
>> I'm doing some work for Mellanox and we need some 100GBase types for
>> coming hardware products too.
>
>> I think we are not using the 32-bits of "ifm_media" well enough.
>
>> Has it been discussed to add more bits to "IFM_NMASK" and have more
>> ethernet types like IFM_ETHER_0, IFM_ETHER_1, IFM_ETHER_2, IFM_ETHER_3 ....
>
>> Currently 5 IFM types are defined. If 2 more bits can be added to
>> IFM_NMASK we have 5 bits total giving us 2**5 = 32 IFM types. Then it
>> should be possible to define "(32 - 5) * 32 = 864" more ethernet types,
>> which I think should be enough for now - or we add even one more bit to
>> IFM_NMASK ?
>
> Did you have specific bits in mind?  I'm fairly sure they are all assigned
> to something now.  The adjacent bits are used for the subtype/variant and
> options.  Most of the options are used, maybe not all.
>
> I haven't checked whether the "instance" field is still used, though.  It
> was for MII PHY numbers, I believe.
>
> If we had more bits, it seems better to put them directly into the subtype
> field rather than the type field.
>
> 		Mike
>

Hi,

There are 6 token ring bits, which I presume are available when token 
ring is not selected.

#define IFM_TOK_ETR     0x00000200      /* Early token release */
#define IFM_TOK_SRCRT   0x00000400      /* Enable source routing features */
#define IFM_TOK_ALLR    0x00000800      /* All routes / Single route 
bcast */
#define IFM_TOK_DTR     0x00002000      /* Dedicated token ring */
#define IFM_TOK_CLASSIC 0x00004000      /* Classic token ring */
#define IFM_TOK_AUTO    0x00008000      /* Automatic Dedicate/Classic 
token ring */

Maybe these can be used for other purposes when the type is equal to 
ethernet?

--HPS



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