[net-next: PATCH 0/8] Armada 7k/8k PP2 ACPI support

Andrew Lunn andrew at lunn.ch
Wed Jan 3 05:33:41 PST 2018


On Wed, Jan 03, 2018 at 02:13:09PM +0100, Marcin Wojtas wrote:
> Hi Andrew,
> 
> 2018-01-03 13:47 GMT+01:00 Andrew Lunn <andrew at lunn.ch>:
> >> I already agreed with 'reg' being awkward in the later emails.
> >> Wouldn't _ADR be more appropriate to specify PHY address on MDIO bus?
> >
> > Also, how do you specify which MDIO bus the PHY is on. To fully
> > specify a PHY, you need both bits of information.
> >
> > In DT, the phy-handle phandle can point to any PHY anywhere in the
> > system. This is particularly important when a Ethernet device has two
> > MDIO busses.
> >
> 
> For now, my local MDIO bus description is pretty DT-like, i.e. master
> bus with children PHYs:
>         Device (MDIO)
>         {
>             Name (_HID, "MRVL0100")                             //
> _HID: Hardware ID
>             Name (_UID, 0x00)                                   //
> _UID: Unique ID
>             Name (_CRS, ResourceTemplate ()
>             {
>                 Memory32Fixed (ReadWrite,
>                     0xf212a200,                                 // Address Base
>                     0x00000010,                                 //
> Address Length
>                     )
>             })
>             Device (GPHY)
>             {
>               Name (_ADR, 0x0)
>             }
>         }
> 
>         Device (XSMI)
>         {
>             Name (_HID, "MRVL0101")                             //
> _HID: Hardware ID
>             Name (_UID, 0x00)                                   //
> _UID: Unique ID
>             Name (_CRS, ResourceTemplate ()
>             {
>                 Memory32Fixed (ReadWrite,
>                     0xf212a600,                                 // Address Base
>                     0x00000010,                                 //
> Address Length
>                     )
>             })
>             Device (PHY0)
>             {
>               Name (_ADR, 0x0)
>               Name (_CID, "ethernet-phy-ieee802.3-c45")
>             }
>             Device (PHY8)
>             {
>               Name (_ADR, 0x8)
>               Name (_CID, "ethernet-phy-ieee802.3-c45")
>             }
>         }
> 
> Which is referenced in the port's node:
> 
> Package () { "phy", Package (){\_SB.XSMI.PHY0}},

Hi Marcin

This reference looks good, giving both the bus and the PHY on the bus.

I assume you can use references like this within the Device (PHY8)
node? You need to be able to reference a GPIO used for resetting the
PHY. And you also need to reference a GPIO at the Device (MDIO) level
for resetting all the PHYs on the MDIO bus.

    Andrew



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