Aw: Re: Re: Re: Re: [PATCH v2] net: mtk_sgmii: implement mtk_pcs_ops

Frank Wunderlich frank-w at public-files.de
Sat Oct 22 10:53:16 PDT 2022


> Gesendet: Samstag, 22. Oktober 2022 um 19:05 Uhr
> Von: "Russell King (Oracle)" <linux at armlinux.org.uk>
> On Sat, Oct 22, 2022 at 12:52:00PM +0200, Frank Wunderlich wrote:
> > > Gesendet: Samstag, 22. Oktober 2022 um 11:11 Uhr
> > > Von: "Russell King (Oracle)" <linux at armlinux.org.uk>

> > this patch breaks connectivity at least on the sfp-port (eth1).

> > pcs_get_state
> > [   65.522936] offset:0 0x2c1140
> > [   65.522950] offset:4 0x4d544950
> > [   65.525914] offset:8 0x40e041a0
> > [  177.346183] offset:0 0x2c1140
> > [  177.346202] offset:4 0x4d544950
> > [  177.349168] offset:8 0x40e041a0
> > [  177.352477] offset:0 0x2c1140
> > [  177.356952] offset:4 0x4d544950
>
> Hi,
>
> Thanks. Well, the results suggest that the register at offset 8 is
> indeed the advertisement and link-partner advertisement register. So
> we have a bit of progress and a little more understanding of this
> hardware.
>
> Do you know if your link partner also thinks the link is up?

yes link is up on my switch, cannot enable autoneg for fibre-port, so port is fixed to 1000M/full flowcontrol enabled.

> What I notice is:
>
> mtk_soc_eth 15100000.ethernet eth1: Link is Up - 1Gbps/Unknown - flow control off
>
> The duplex is "unknown" which means you're not filling in the
> state->duplex field in your pcs_get_state() function. Given the
> link parter adverisement is 0x00e0, this means the link partner
> supports PAUSE, 1000base-X/Half and 1000base-X/Full. The resolution
> is therefore full duplex, so can we hack that in to your
> pcs_get_state() so we're getting that right for this testing please?

0xe0 is bits 5-7 are set (in lower byte from upper word)..which one is for duplex?

so i should set state->duplex/pause based on this value (maybe compare with own caps)?

found a documentation where 5=full,6=half, and bits 7+8 are for pause (symetric/asymetric)

regmap_read(mpcs->regmap, SGMSYS_PCS_CONTROL_1+8, &val);
partner_advertising = (val & 0x00ff0000) >> 16;

if (partner_advertising & BIT(5)) state->duplex = DUPLEX_FULL;
else if (partner_advertising & BIT(6)) state->duplex = DUPLEX_HALF;

if (partner_advertising & BIT(7)) state->pause = MAC_SYM_PAUSE;
else if (partner_advertising & BIT(8)) state->pause = MAC_ASYM_PAUSE;

> Now, I'm wondering what SGMII_IF_MODE_BIT0 and SGMII_IF_MODE_BIT5 do
> in the SGMSYS_SGMII_MODE register. Does one of these bits set the
> format for the 16-bit control word that's used to convey the
> advertisements. I think the next step would be to play around with
> these and see what effect setting or clearing these bits has -
> please can you give that a go?

these is not clear to me...should i blindly set these and how to verify what they do?

is network broken because of wrong duplex/pause setting? do not fully understand your Patch.
But the timer-change can also break sgmii...

regards Frank



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