Re: [PATCH 2/2] ARM: dts: ls1021a-tsn: Use interrupts for the SGMII PHYs

[Vladimir Oltean]

On Tue, 12 Nov 2019 at 15:49, Marc Zyngier <maz@xxxxxxxxxx> wrote:
>
> On 2019-11-12 14:53, Vladimir Oltean wrote:
> > On Tue, 12 Nov 2019 at 15:20, Rasmus Villemoes
> > <linux@xxxxxxxxxxxxxxxxxx> wrote:
> >>
> >> From: Vladimir Oltean <olteanv@xxxxxxxxx>
> >>
> >> On the LS1021A-TSN board, the 2 Atheros AR8031 PHYs for eth0 and
> >> eth1
> >> have interrupt lines connected to the shared IRQ2_B LS1021A pin.
> >>
> >> Switching to interrupts offloads the PHY library from the task of
> >> polling the MDIO status and AN registers (1, 4, 5) every second.
> >>
> >> Unfortunately, the BCM5464R quad PHY connected to the switch does
> >> not
> >> appear to have an interrupt line routed to the SoC.
> >>
> >> Signed-off-by: Vladimir Oltean <olteanv@xxxxxxxxx>
> >> Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
> >> ---
> >>  arch/arm/boot/dts/ls1021a-tsn.dts | 4 ++++
> >>  1 file changed, 4 insertions(+)
> >>
> >> diff --git a/arch/arm/boot/dts/ls1021a-tsn.dts
> >> b/arch/arm/boot/dts/ls1021a-tsn.dts
> >> index 5b7689094b70..135d36461af4 100644
> >> --- a/arch/arm/boot/dts/ls1021a-tsn.dts
> >> +++ b/arch/arm/boot/dts/ls1021a-tsn.dts
> >> @@ -203,11 +203,15 @@
> >>         /* AR8031 */
> >>         sgmii_phy1: ethernet-phy@1 {
> >>                 reg = <0x1>;
> >> +               /* SGMII1_PHY_INT_B: connected to IRQ2, active low
> >> */
> >> +               interrupts-extended = <&extirq 2
> >> IRQ_TYPE_EDGE_FALLING>;
> >>         };
> >>
> >>         /* AR8031 */
> >>         sgmii_phy2: ethernet-phy@2 {
> >>                 reg = <0x2>;
> >> +               /* SGMII2_PHY_INT_B: connected to IRQ2, active low
> >> */
> >> +               interrupts-extended = <&extirq 2
> >> IRQ_TYPE_EDGE_FALLING>;
> >>         };
> >>
> >>         /* BCM5464 quad PHY */
> >> --
> >> 2.23.0
> >>
> >
> > +netdev and Andrew for this patch, since the interrupt polarity
> > caught
> > his attention in v1.
>
> Certainly, the comments and the interrupt specifier do not match.
> Which one is true?
>
>          M.
> --
> Jazz is not dead. It just smells funny...

The interrupt specifier certainly works. So that points to an issue
with the description. What do you mean, exactly? Does "active low"
mean "level-triggered"? How would you have described this?