RE: [PATCH v5 net 3/3] net: enetc: do not access non-existent registers on pseudo MAC

[Wei Fang]

> > -----Original Message-----
> > From: Wei Fang <wei.fang@xxxxxxx>
> > Sent: Friday, March 13, 2026 11:47 AM
> [...]
> > Subject: [PATCH v5 net 3/3] net: enetc: do not access non-existent
> > registers on pseudo MAC
> >
> > The ENETC4_PM_IEVENT and ENETC4_PM_CMD_CFG registers do not exist
> on
> > the ENETC pseudo MAC, so the driver should prevent from accessing
> > them.
> >
> > Fixes: 5175c1e4adca ("net: enetc: add basic support for the ENETC with
> > pseudo MAC for i.MX94")
> > Signed-off-by: Wei Fang <wei.fang@xxxxxxx>
> > ---
> > Note that the commit 5175c1e4adca ("net: enetc: add basic support for
> > the ENETC with pseudo MAC for i.MX94") does not have such issue, this
> > patch depends on the patch 2 in this patch set.
> > ---
> >  drivers/net/ethernet/freescale/enetc/enetc4_pf.c | 7 +++++++
> >  1 file changed, 7 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/freescale/enetc/enetc4_pf.c
> > b/drivers/net/ethernet/freescale/enetc/enetc4_pf.c
> > index 53cecbb23a97..56899f2254aa 100644
> > --- a/drivers/net/ethernet/freescale/enetc/enetc4_pf.c
> > +++ b/drivers/net/ethernet/freescale/enetc/enetc4_pf.c
> > @@ -814,6 +814,9 @@ static void enetc4_mac_tx_graceful_stop(struct
> > enetc_pf
> > *pf)
> >  	val |= POR_TXDIS;
> >  	enetc_port_wr(hw, ENETC4_POR, val);
> >
> > +	if (enetc_is_pseudo_mac(si))
> > +		return;
> > +
> 
> Shouldn't the ~PM_CMD_CFG_TX_EN step apply to pseudo-MACs too?

Based on the NETC block guide, the pseudo MAC does not have
PMa_COMMAND_CONFIG register. So no need to set PM_CMD_CFG_TX_EN
and PM_CMD_CFG_RX_EN bits for pseudo MAC.

> 
> >  	enetc4_mac_wait_tx_empty(si, 0);
> >  	if (si->hw_features & ENETC_SI_F_QBU)
> >  		enetc4_mac_wait_tx_empty(si, 1);
> > @@ -856,6 +859,9 @@ static void enetc4_mac_rx_graceful_stop(struct
> > enetc_pf
> > *pf)
> >  	struct enetc_si *si = pf->si;
> >  	u32 val;
> >
> > +	if (enetc_is_pseudo_mac(si))
> > +		goto check_rx_busy;
> > +
> 
> Shouldn't the ~PM_CMD_CFG_RX_EN step apply to pseudo-MACs too?
> 
> >  	if (si->hw_features & ENETC_SI_F_QBU) {
> >  		val = enetc_port_rd(hw, ENETC4_PM_CMD_CFG(1));
> >  		val &= ~PM_CMD_CFG_RX_EN;
> > @@ -868,6 +874,7 @@ static void enetc4_mac_rx_graceful_stop(struct
> > enetc_pf
> > *pf)
> >  	enetc_port_wr(hw, ENETC4_PM_CMD_CFG(0), val);
> >  	enetc4_mac_wait_rx_empty(si, 0);
> >
> > +check_rx_busy:
> >  	if (read_poll_timeout(enetc_port_rd, val,
> >  			      !(val & PSR_RX_BUSY),
> >  			      100, 10000, false, hw,
> > --
> > 2.34.1