Quoting Andrew Lunn <and...@lunn.ch>:
Hi Andrew,
On Tue, Jun 25, 2019 at 02:27:55PM -0500, Daniel Santos wrote:
On 6/25/19 2:02 PM, Andrew Lunn wrote:
>> But will there still be a mechanism to ignore link partner's advertising
>> and force these parameters?
> >From man 1 ethtool:
>
> -a --show-pause
> Queries the specified Ethernet device for pause
parameter information.
>
> -A --pause
> Changes the pause parameters of the specified
Ethernet device.
>
> autoneg on|off
> Specifies whether pause autonegotiation should
be enabled.
>
> rx on|off
> Specifies whether RX pause should be enabled.
>
> tx on|off
> Specifies whether TX pause should be enabled.
>
> You need to check the driver to see if it actually implements this
> ethtool call, but that is how it should be configured.
>
> Andrew
>
Thank you Andrew,
So in this context, my question is the difference between "enabling" and
"forcing". Here's that register for the mt7620 (which has an mt7530 on
its die): https://imgur.com/a/pTk0668 I believe this is also what René
is seeking clarity on?
Lets start with normal operation. If the MAC supports pause or asym
pause, it calls phy_support_sym_pause() or phy_support_asym_pause().
phylib will then configure the PHY to advertise pause as appropriate.
Once auto-neg has completed, the results of the negotiation are set in
phydev. So phdev->pause and phydev->asym_pause. The MAC callback is
then used to tell the MAC about the autoneg results. The MAC should be
programmed using the values in phdev->pause and phydev->asym_pause.
For ethtool, the MAC driver needs to implement .get_pauseparam and
.set_pauseparam. The set_pauseparam needs to validate the settings,
using phy_validate_pause(). If valid, phy_set_asym_pause() is used to
tell the PHY about the new configuration. This will trigger a new
auto-neg if auto-neg is enabled, and the results will be passed back
in the usual way. If auto-neg is disabled, or pause auto-neg is
disabled, the MAC should configure pause directly based on the
settings passed.
Looking at the data sheet page, you want FORCE_MODE_Pn set. You never
want the MAC directly talking to the PHY. Bad things will happen.
Then use FORCE_RX_FC_Pn and FORCE_TX_Pn to reflect phydev->pause and
phydev->asym_pause.
The same idea applies when using phylink.
Thanks for this information.
I updated mt7530_phylink_mac_config(), I think I done it right this time
with the pause bits.
Now mt7530_phylink_mac_config() looks like this:
static void mt7530_phylink_mac_config(struct dsa_switch *ds, int port,
unsigned int mode,
const struct phylink_link_state *state)
{
struct mt7530_priv *priv = ds->priv;
u32 mcr_cur, mcr_new = 0;
switch (port) {
case 0: /* Internal phy */
case 1:
case 2:
case 3:
case 4:
if (state->interface != PHY_INTERFACE_MODE_GMII)
return;
break;
case 5: /* 2nd cpu port with phy of port 0 or 4 / external phy */
if (!phy_interface_mode_is_rgmii(state->interface) &&
state->interface != PHY_INTERFACE_MODE_MII)
return;
if (priv->p5_intf_sel != P5_INTF_SEL_GMAC5) {
priv->p5_intf_sel = P5_INTF_SEL_GMAC5;
mt7530_setup_port5(ds, state->interface);
}
/* We are connected to external phy */
if (dsa_is_user_port(ds, 5))
mcr_new |= PMCR_EXT_PHY;
break;
case 6: /* 1st cpu port */
if (state->interface != PHY_INTERFACE_MODE_RGMII &&
state->interface != PHY_INTERFACE_MODE_TRGMII)
return;
if (priv->p6_interface == state->interface)
break;
/* Setup TX circuit incluing relevant PAD and driving */
mt7530_pad_clk_setup(ds, state->interface);
if (priv->id == ID_MT7530) {
/* Setup RX circuit, relevant PAD and driving on the
* host which must be placed after the setup on the
* device side is all finished.
*/
mt7623_pad_clk_setup(ds);
}
priv->p6_interface = state->interface;
break;
default:
dev_err(ds->dev, "%s: unsupported port: %i\n", __func__, port);
return;
}
mcr_cur = mt7530_read(priv, MT7530_PMCR_P(port));
mcr_new |= mcr_cur;
mcr_new &= ~(PMCR_FORCE_SPEED_1000 | PMCR_FORCE_SPEED_100 |
PMCR_FORCE_FDX | PMCR_TX_FC_EN | PMCR_RX_FC_EN);
mcr_new |= PMCR_IFG_XMIT(1) | PMCR_MAC_MODE | PMCR_BACKOFF_EN |
PMCR_BACKPR_EN | PMCR_FORCE_MODE | PMCR_FORCE_LNK;
switch (state->speed) {
case SPEED_1000:
mcr_new |= PMCR_FORCE_SPEED_1000;
break;
case SPEED_100:
mcr_new |= PMCR_FORCE_SPEED_100;
break;
}
if (state->duplex == DUPLEX_FULL) {
mcr_new |= PMCR_FORCE_FDX;
if (state->pause & MLO_PAUSE_TX)
mcr_new |= PMCR_TX_FC_EN;
if (state->pause & MLO_PAUSE_RX)
mcr_new |= PMCR_RX_FC_EN;
}
if (mcr_new != mcr_cur)
mt7530_write(priv, MT7530_PMCR_P(port), mcr_new);
}
Greats,
René
