git: b329bb8fd7b6 - stable/13 - mii_fdt: Add support for switch PHY node lookup

[Marcin Wojtas]

The branch stable/13 has been updated by mw:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=b329bb8fd7b64e85243b1a90c388ed5c332ea812

commit b329bb8fd7b64e85243b1a90c388ed5c332ea812
Author:     Kornel Duleba <min...@semihalf.com>
AuthorDate: 2021-10-27 08:34:17 +0000
Commit:     Marcin Wojtas <m...@freebsd.org>
CommitDate: 2022-03-29 22:24:27 +0000

    mii_fdt: Add support for switch PHY node lookup
    
    Previously we would only search for a PHY xref in node of the miibus
    parent.
    That didn't work very well with switches.
    Fix that by searching through "ports" subnode, checking if any of its
    children have a valid PHY xref.
    Since switches tend to have multiple ports we also have multiple
    candidates.
    Use the PHY address read from mii_attach_args to find the right one.
    
    Obtained from: Semihalf
    Sponsored by: Alstom Group
    Reviewed by: mw
    Differential revision: https://reviews.freebsd.org/D32690
    
    (cherry picked from commit 4b843e7f0319867c412070e7752dbb47f195b322)
---
 sys/dev/mii/mii_fdt.c | 43 ++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/sys/dev/mii/mii_fdt.c b/sys/dev/mii/mii_fdt.c
index 009a523e32ce..18ed9c8e749c 100644
--- a/sys/dev/mii/mii_fdt.c
+++ b/sys/dev/mii/mii_fdt.c
@@ -99,6 +99,44 @@ mii_fdt_get_phynode(phandle_t macnode)
        return (-1);
 }
 
+static phandle_t
+mii_fdt_lookup_phy(phandle_t node, int addr)
+{
+       phandle_t ports, phynode, child;
+       int reg;
+
+       /* First try to see if we have a direct xref pointing to a PHY. */
+       phynode = mii_fdt_get_phynode(node);
+       if (phynode != -1)
+               return (phynode);
+
+       /*
+        * Now handle the "switch" case.
+        * Search "ports" subnode for nodes that describe a switch port
+        * including a PHY xref.
+        * Since we have multiple candidates select one based on PHY address.
+        */
+       ports = ofw_bus_find_child(node, "ports");
+       if (ports <= 0)
+               return (-1);
+
+       for (child = OF_child(ports); child != 0; child = OF_peer(child)) {
+               if (ofw_bus_node_status_okay(child) == 0)
+                       continue;
+
+               phynode = mii_fdt_get_phynode(child);
+               if (phynode <= 0)
+                       continue;
+
+               if (OF_getencprop(phynode, "reg", &reg, sizeof(reg)) <= 0)
+                       continue;
+
+               if (reg == addr)
+                       return (phynode);
+       }
+       return (-1);
+}
+
 mii_contype_t
 mii_fdt_contype_from_name(const char *name)
 {
@@ -145,10 +183,12 @@ mii_fdt_free_config(struct mii_fdt_phy_config *cfg)
 mii_fdt_phy_config_t *
 mii_fdt_get_config(device_t phydev)
 {
+       struct mii_attach_args *ma;
        mii_fdt_phy_config_t *cfg;
        device_t miibus, macdev;
        pcell_t val;
 
+       ma = device_get_ivars(phydev);
        miibus = device_get_parent(phydev);
        macdev = device_get_parent(miibus);
 
@@ -167,7 +207,8 @@ mii_fdt_get_config(device_t phydev)
         * If we can't find our own PHY node, there's nothing more we can fill
         * in, just return what we've got.
         */
-       if ((cfg->phynode = mii_fdt_get_phynode(cfg->macnode)) == -1)
+       cfg->phynode = mii_fdt_lookup_phy(cfg->macnode, ma->mii_phyno);
+       if (cfg->phynode == -1)
                return (cfg);
 
        if (OF_getencprop(cfg->phynode, "max-speed", &val, sizeof(val)) > 0)