Re: [PATCH 4/4] net: dsa: mv88e6xxx: Support serdes ports on MV88E6123/6131

[Andrew Lunn]

On Tue, Oct 27, 2020 at 08:56:09PM +0000, Chris Packham wrote:
> 
> On 24/10/20 11:42 am, Andrew Lunn wrote:
> >> +int mv88e6123_serdes_get_regs_len(struct mv88e6xxx_chip *chip, int port)
> >> +{
> >> +	if (mv88e6xxx_serdes_get_lane(chip, port) == 0)
> >> +		return 0;
> >> +
> >> +	return 26 * sizeof(u16);
> >> +}
> > Hi Chris
> >
> > Where did 26 come from?

> In the 88E6123 Serdes Register Description the highest register address 
> was 26 so that's what I used.

> Technically there are 32 possible 
> addresses in that space so I could go up to 32. Equally registers 9-14, 
> 20, 22-23 are "reserved" so I could remove them from the total and have 
> mv88e6123_serdes_get_regs() skip over them. I'm guessing skipping some 
> (27-32) and not others is probably less than ideal.

Hi Chris

I would dump all 32 and let userspace figure out if they mean
anything. The current register dump for the 6390 SEDES is horrible,
and i missed a register, and it is not easy to put in its correct
place because of ABI reasons. If you can do KISS, all the better.

      Andrew