Add a NetBSD-compatible mii_attach(), which is intended to eventually

replace mii_phy_probe() altogether. Compared to the latter the advantages
of mii_attach() are:
- intended to be called multiple times in order to attach PHYs in multiple
  passes (f.e. in order to only use sub-ranges of the 0 to MII_NPHY - 1
  range)
- being able to pass along the capability mask from the NIC to the PHY
  drivers
- being able to specify at which address (phyloc) to probe for a PHY
  (instead of always probing at all addresses from 0 to MII_NPHY - 1)
- being able to specify which PHY instance (offloc) to attach
- being able to pass along MIIF_* flags from the NIC to the PHY drivers
  (f.e. as required to indicated to the PHY drivers that flow control is
  supported by the NIC driver, which actually is the motivation for this
  change).

While at it, I used the opportunity to get rid of some hacks in mii(4)
like miibus_probe() generally doing work besides sheer probing and the
"EVIL HACK" (which will vanish entirely along with mii_phy_probe()) by
passing the struct ifnet pointer via an argument of mii_attach() as well
as to fix some resource leaks in mii(4) in case something fails.
Commits which will update the PHY drivers to honor the MII flags passed
down from the NIC drivers and take advantage of mii_attach() to get rid
of certain types of hacks in NIC and PHY drivers as well as a conversion
of the remaining uses of mii_phy_probe() will follow shortly.

Reviewed by:	jhb, yongari
Obtained from:	NetBSD (partially)

3 files changed, 255 insertions, 99 deletions

diff --git a/sys/dev/mii/mii.c b/sys/dev/mii/mii.c
index f19fcc2a0a85..263a18b4de35 100644
--- a/sys/dev/mii/mii.c
+++ b/sys/dev/mii/mii.c
@@ -58,6 +58,8 @@ MODULE_VERSION(miibus, 1);
 #include "miibus_if.h"
 
 static int miibus_print_child(device_t dev, device_t child);
+static int miibus_read_ivar(device_t dev, device_t child, int which,
+    uintptr_t *result);
 static int miibus_child_location_str(device_t bus, device_t child, char *buf,
     size_t buflen);
 static int miibus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
@@ -77,6 +79,7 @@ static device_method_t miibus_methods[] = {
 
 	/* bus interface */
 	DEVMETHOD(bus_print_child,	miibus_print_child),
+	DEVMETHOD(bus_read_ivar,	miibus_read_ivar),
 	DEVMETHOD(bus_driver_added,	bus_generic_driver_added),
 	DEVMETHOD(bus_child_pnpinfo_str, miibus_child_pnpinfo_str),
 	DEVMETHOD(bus_child_location_str, miibus_child_location_str),
@@ -100,87 +103,52 @@ driver_t miibus_driver = {
 };
 
 struct miibus_ivars {
+	struct ifnet	*ifp;
 	ifm_change_cb_t	ifmedia_upd;
 	ifm_stat_cb_t	ifmedia_sts;
+	int		mii_flags;
 };
 
-/*
- * Helper function used by network interface drivers, attaches PHYs
- * to the network interface driver parent.
- */
 int
 miibus_probe(device_t dev)
 {
-	struct mii_attach_args	ma, *args;
-	struct mii_data		*mii;
-	device_t		child = NULL, parent;
-	int			bmsr, capmask = 0xFFFFFFFF;
-
-	mii = device_get_softc(dev);
-	parent = device_get_parent(dev);
-	LIST_INIT(&mii->mii_phys);
-
-	for (ma.mii_phyno = 0; ma.mii_phyno < MII_NPHY; ma.mii_phyno++) {
-		/*
-		 * Check to see if there is a PHY at this address.  Note,
-		 * many braindead PHYs report 0/0 in their ID registers,
-		 * so we test for media in the BMSR.
-	 	 */
-		bmsr = MIIBUS_READREG(parent, ma.mii_phyno, MII_BMSR);
-		if (bmsr == 0 || bmsr == 0xffff ||
-		    (bmsr & (BMSR_EXTSTAT | BMSR_MEDIAMASK)) == 0) {
-			/* Assume no PHY at this address. */
-			continue;
-		}
-
-		/*
-		 * Extract the IDs. Braindead PHYs will be handled by
-		 * the `ukphy' driver, as we have no ID information to
-		 * match on.
-	 	 */
-		ma.mii_id1 = MIIBUS_READREG(parent, ma.mii_phyno,
-		    MII_PHYIDR1);
-		ma.mii_id2 = MIIBUS_READREG(parent, ma.mii_phyno,
-		    MII_PHYIDR2);
-
-		ma.mii_data = mii;
-		ma.mii_capmask = capmask;
-
-		args = malloc(sizeof(struct mii_attach_args),
-		    M_DEVBUF, M_NOWAIT);
-		bcopy((char *)&ma, (char *)args, sizeof(ma));
-		child = device_add_child(dev, NULL, -1);
-		device_set_ivars(child, args);
-	}
-
-	if (child == NULL)
-		return (ENXIO);
 
 	device_set_desc(dev, "MII bus");
 
-	return (0);
+	return (BUS_PROBE_SPECIFIC);
 }
 
 int
 miibus_attach(device_t dev)
 {
 	struct miibus_ivars	*ivars;
+	struct mii_attach_args	*ma;
 	struct mii_data		*mii;
+	device_t		*children;
+	int			i, nchildren;
 
 	mii = device_get_softc(dev);
-	/*
-	 * Note that each NIC's softc must start with an ifnet pointer.
-	 * XXX: EVIL HACK!
-	 */
-	mii->mii_ifp = *(struct ifnet**)device_get_softc(device_get_parent(dev));
-	mii->mii_ifp->if_capabilities |= IFCAP_LINKSTATE;
-	mii->mii_ifp->if_capenable |= IFCAP_LINKSTATE;
+	nchildren = 0;
+	if (device_get_children(dev, &children, &nchildren) == 0) {
+		for (i = 0; i < nchildren; i++) {
+			ma = device_get_ivars(children[i]);
+			ma->mii_data = mii;
+		}
+		free(children, M_TEMP);
+	}
+	if (nchildren == 0) {
+		device_printf(dev, "cannot get children");
+		return (ENXIO);
+	}
 	ivars = device_get_ivars(dev);
 	ifmedia_init(&mii->mii_media, IFM_IMASK, ivars->ifmedia_upd,
 	    ivars->ifmedia_sts);
-	bus_generic_attach(dev);
+	mii->mii_ifp = ivars->ifp;
+	mii->mii_ifp->if_capabilities |= IFCAP_LINKSTATE;
+	mii->mii_ifp->if_capenable |= IFCAP_LINKSTATE;
+	LIST_INIT(&mii->mii_phys);
 
-	return (0);
+	return (bus_generic_attach(dev));
 }
 
 int
@@ -211,7 +179,28 @@ miibus_print_child(device_t dev, device_t child)
 }
 
 static int
-miibus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
+miibus_read_ivar(device_t dev, device_t child __unused, int which,
+    uintptr_t *result)
+{
+	struct miibus_ivars *ivars;
+
+	/*
+	 * NB: this uses the instance variables of the miibus rather than
+	 * its PHY children.
+	 */
+	ivars = device_get_ivars(dev);
+	switch (which) {
+	case MIIBUS_IVAR_FLAGS:
+		*result = ivars->mii_flags;
+		break;
+	default:
+		return (ENOENT);
+	}
+	return (0);
+}
+
+static int
+miibus_child_pnpinfo_str(device_t bus __unused, device_t child, char *buf,
     size_t buflen)
 {
 	struct mii_attach_args *ma;
@@ -224,7 +213,7 @@ miibus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
 }
 
 static int
-miibus_child_location_str(device_t bus, device_t child, char *buf,
+miibus_child_location_str(device_t bus __unused, device_t child, char *buf,
     size_t buflen)
 {
 	struct mii_attach_args *ma;
@@ -307,40 +296,177 @@ miibus_mediainit(device_t dev)
 	ifmedia_set(&mii->mii_media, media);
 }
 
+/*
+ * Helper function used by network interface drivers, attaches the miibus and
+ * the PHYs to the network interface driver parent.
+ */
 int
-mii_phy_probe(device_t dev, device_t *child, ifm_change_cb_t ifmedia_upd,
-    ifm_stat_cb_t ifmedia_sts)
+mii_attach(device_t dev, device_t *miibus, struct ifnet *ifp,
+    ifm_change_cb_t ifmedia_upd, ifm_stat_cb_t ifmedia_sts, int capmask,
+    int phyloc, int offloc, int flags)
 {
-	struct miibus_ivars	*ivars;
-	int			bmsr, i;
-
-	ivars = malloc(sizeof(*ivars), M_DEVBUF, M_NOWAIT);
-	if (ivars == NULL)
-		return (ENOMEM);
-	ivars->ifmedia_upd = ifmedia_upd;
-	ivars->ifmedia_sts = ifmedia_sts;
-	*child = device_add_child(dev, "miibus", -1);
-	device_set_ivars(*child, ivars);
-
-	for (i = 0; i < MII_NPHY; i++) {
-		bmsr = MIIBUS_READREG(dev, i, MII_BMSR);
-                if (bmsr == 0 || bmsr == 0xffff ||
-                    (bmsr & (BMSR_EXTSTAT | BMSR_MEDIAMASK)) == 0) {
-                        /* Assume no PHY at this address. */
-                        continue;
-                } else
-			break;
+	struct miibus_ivars *ivars;
+	struct mii_attach_args ma, *args;
+	device_t *children, phy;
+	int bmsr, first, i, nchildren, offset, phymax, phymin, rv;
+
+	if (phyloc != MII_PHY_ANY && offloc != MII_OFFSET_ANY) {
+		printf("%s: phyloc and offloc specified", __func__);
+		return (EINVAL);
 	}
 
-	if (i == MII_NPHY) {
-		device_delete_child(dev, *child);
-		*child = NULL;
-		return (ENXIO);
+	if (offloc != MII_OFFSET_ANY && (offloc < 0 || offloc >= MII_NPHY)) {
+		printf("%s: ivalid offloc %d", __func__, offloc);
+		return (EINVAL);
+	}
+
+	if (phyloc == MII_PHY_ANY) {
+		phymin = 0;
+		phymax = MII_NPHY - 1;
+	} else {
+		if (phyloc < 0 || phyloc >= MII_NPHY) {
+			printf("%s: ivalid phyloc %d", __func__, phyloc);
+			return (EINVAL);
+		}
+		phymin = phymax = phyloc;
 	}
 
-	bus_generic_attach(dev);
+	first = 0;
+	if (*miibus == NULL) {
+		first = 1;
+		ivars = malloc(sizeof(*ivars), M_DEVBUF, M_NOWAIT);
+		if (ivars == NULL)
+			return (ENOMEM);
+		ivars->ifp = ifp;
+		ivars->ifmedia_upd = ifmedia_upd;
+		ivars->ifmedia_sts = ifmedia_sts;
+		ivars->mii_flags = flags;
+		*miibus = device_add_child(dev, "miibus", -1);
+		if (*miibus == NULL) {
+			rv = ENXIO;
+			goto fail;
+		}
+		device_set_ivars(*miibus, ivars);
+	} else {
+		ivars = device_get_ivars(*miibus);
+		if (ivars->ifp != ifp || ivars->ifmedia_upd != ifmedia_upd ||
+		    ivars->ifmedia_sts != ifmedia_sts ||
+		    ivars->mii_flags != flags) {
+			printf("%s: non-matching invariant", __func__);
+			return (EINVAL);
+		}
+		/*
+		 * Assignment of the attach arguments mii_data for the first
+		 * pass is done in miibus_attach(), i.e. once the miibus softc
+		 * has been allocated.
+		 */
+		ma.mii_data = device_get_softc(*miibus);
+	} 
+
+	ma.mii_capmask = capmask;
+
+	phy = NULL;
+	offset = 0;
+	for (ma.mii_phyno = phymin; ma.mii_phyno <= phymax; ma.mii_phyno++) {
+		/*
+		 * Make sure we haven't already configured a PHY at this
+		 * address.  This allows mii_attach() to be called
+		 * multiple times.
+		 */
+		if (device_get_children(*miibus, &children, &nchildren) == 0) {
+			for (i = 0; i < nchildren; i++) {
+				args = device_get_ivars(children[i]);
+				if (args->mii_phyno == ma.mii_phyno) {
+					/*
+					 * Yes, there is already something
+					 * configured at this address.
+					 */
+					free(children, M_TEMP);
+					goto skip;
+				}
+			}
+			free(children, M_TEMP);
+		}
+
+		/*
+		 * Check to see if there is a PHY at this address.  Note,
+		 * many braindead PHYs report 0/0 in their ID registers,
+		 * so we test for media in the BMSR.
+	 	 */
+		bmsr = MIIBUS_READREG(dev, ma.mii_phyno, MII_BMSR);
+		if (bmsr == 0 || bmsr == 0xffff ||
+		    (bmsr & (BMSR_EXTSTAT | BMSR_MEDIAMASK)) == 0) {
+			/* Assume no PHY at this address. */
+			continue;
+		}
+
+		/*
+		 * There is a PHY at this address.  If we were given an
+		 * `offset' locator, skip this PHY if it doesn't match.
+		 */
+		if (offloc != MII_OFFSET_ANY && offloc != offset)
+			goto skip;
+
+		/*
+		 * Extract the IDs. Braindead PHYs will be handled by
+		 * the `ukphy' driver, as we have no ID information to
+		 * match on.
+	 	 */
+		ma.mii_id1 = MIIBUS_READREG(dev, ma.mii_phyno, MII_PHYIDR1);
+		ma.mii_id2 = MIIBUS_READREG(dev, ma.mii_phyno, MII_PHYIDR2);
+
+		args = malloc(sizeof(struct mii_attach_args), M_DEVBUF,
+		    M_NOWAIT);
+		if (args == NULL)
+			goto skip;
+		bcopy((char *)&ma, (char *)args, sizeof(ma));
+		phy = device_add_child(*miibus, NULL, -1);
+		if (phy == NULL) {
+			free(args, M_DEVBUF);
+			goto skip;
+		}
+		device_set_ivars(phy, args);
+ skip:
+		offset++;
+	}
+
+	if (first != 0) {
+		if (phy == NULL) {
+			rv = ENXIO;
+			goto fail;
+		}
+		rv = bus_generic_attach(dev);
+		if (rv != 0)
+			goto fail;
+	}
+	rv = bus_generic_attach(*miibus);
+	if (rv != 0)
+		goto fail;
 
 	return (0);
+
+ fail:
+	if (*miibus != NULL)
+		device_delete_child(dev, *miibus);
+	free(ivars, M_DEVBUF);
+	if (first != 0)
+		*miibus = NULL;
+	return (rv);
+}
+
+int
+mii_phy_probe(device_t dev, device_t *child, ifm_change_cb_t ifmedia_upd,
+    ifm_stat_cb_t ifmedia_sts)
+{
+	struct ifnet *ifp;
+
+	/*
+	 * Note that each NIC's softc must start with an ifnet pointer.
+	 * XXX: EVIL HACK!
+	 */
+	ifp = *(struct ifnet **)device_get_softc(dev);
+	return (mii_attach(dev, child, ifp, ifmedia_upd, ifmedia_sts,
+	    BMSR_DEFCAPMASK, MII_PHY_ANY, MII_OFFSET_ANY, 0));
 }
 
 /*
diff --git a/sys/dev/mii/mii.h b/sys/dev/mii/mii.h
index c84c76719b72..b7e0a056bb6b 100644
--- a/sys/dev/mii/mii.h
+++ b/sys/dev/mii/mii.h
@@ -1,5 +1,5 @@
 /*	$NetBSD: mii.h,v 1.9 2001/05/31 03:07:14 thorpej Exp $	*/
- 
+
 /*-
  * Copyright (c) 1997 Manuel Bouyer.  All rights reserved.
  *
@@ -47,7 +47,7 @@
 #define	MII_COMMAND_WRITE	0x01
 #define	MII_COMMAND_ACK		0x02
 
-#define	MII_BMCR	0x00 	/* Basic mode control register (rw) */
+#define	MII_BMCR	0x00	/* Basic mode control register (rw) */
 #define	BMCR_RESET	0x8000	/* reset */
 #define	BMCR_LOOP	0x4000	/* loopback */
 #define	BMCR_SPEED0	0x2000	/* speed selection (LSB) */
@@ -82,6 +82,8 @@
 #define	BMSR_JABBER	0x0002	/* Jabber detected */
 #define	BMSR_EXTCAP	0x0001	/* Extended capability */
 
+#define	BMSR_DEFCAPMASK	0xffffffff
+
 /*
  * Note that the EXTSTAT bit indicates that there is extended status
  * info available in register 15, but 802.3 section 22.2.4.3 also
diff --git a/sys/dev/mii/miivar.h b/sys/dev/mii/miivar.h
index 6b5a12172709..9196f8d1ce0f 100644
--- a/sys/dev/mii/miivar.h
+++ b/sys/dev/mii/miivar.h
@@ -102,7 +102,7 @@ typedef	int (*mii_downcall_t)(struct mii_softc *, struct mii_data *, int);
  */
 struct mii_softc {
 	device_t mii_dev;		/* generic device glue */
-	
+
 	LIST_ENTRY(mii_softc) mii_list;	/* entry on parent's PHY list */
 
 	int mii_phy;			/* our MII address */
@@ -122,16 +122,22 @@ struct mii_softc {
 typedef struct mii_softc mii_softc_t;
 
 /* mii_flags */
-#define	MIIF_INITDONE	0x0001		/* has been initialized (mii_data) */
-#define	MIIF_NOISOLATE	0x0002		/* do not isolate the PHY */
-#define	MIIF_NOLOOP	0x0004		/* no loopback capability */
-#define MIIF_AUTOTSLEEP	0x0010		/* use tsleep(), not callout() */
-#define MIIF_HAVEFIBER	0x0020		/* from parent: has fiber interface */
-#define	MIIF_HAVE_GTCR	0x0040		/* has 100base-T2/1000base-T CR */
-#define	MIIF_IS_1000X	0x0080		/* is a 1000BASE-X device */
-#define	MIIF_DOPAUSE	0x0100		/* advertise PAUSE capability */
-#define	MIIF_IS_HPNA	0x0200		/* is a HomePNA device */
-#define	MIIF_FORCEANEG	0x0400		/* force auto-negotiation */
+#define	MIIF_INITDONE	0x00000001	/* has been initialized (mii_data) */
+#define	MIIF_NOISOLATE	0x00000002	/* do not isolate the PHY */
+#define	MIIF_NOLOOP	0x00000004	/* no loopback capability */
+#define	MIIF_AUTOTSLEEP	0x00000010	/* use tsleep(), not callout() */
+#define	MIIF_HAVEFIBER	0x00000020	/* from parent: has fiber interface */
+#define	MIIF_HAVE_GTCR	0x00000040	/* has 100base-T2/1000base-T CR */
+#define	MIIF_IS_1000X	0x00000080	/* is a 1000BASE-X device */
+#define	MIIF_DOPAUSE	0x00000100	/* advertise PAUSE capability */
+#define	MIIF_IS_HPNA	0x00000200	/* is a HomePNA device */
+#define	MIIF_FORCEANEG	0x00000400	/* force auto-negotiation */
+#define	MIIF_MACPRIV0	0x01000000	/* private to the MAC driver */
+#define	MIIF_MACPRIV1	0x02000000	/* private to the MAC driver */
+#define	MIIF_MACPRIV2	0x04000000	/* private to the MAC driver */
+#define	MIIF_PHYPRIV0	0x10000000	/* private to the PHY driver */
+#define	MIIF_PHYPRIV1	0x20000000	/* private to the PHY driver */
+#define	MIIF_PHYPRIV2	0x40000000	/* private to the PHY driver */
 
 /* Default mii_anegticks values */
 #define	MII_ANEGTICKS		5
@@ -140,6 +146,14 @@ typedef struct mii_softc mii_softc_t;
 #define	MIIF_INHERIT_MASK	(MIIF_NOISOLATE|MIIF_NOLOOP|MIIF_AUTOTSLEEP)
 
 /*
+ * Special `locators' passed to mii_attach().  If one of these is not
+ * an `any' value, we look for *that* PHY and configure it.  If both
+ * are not `any', that is an error, and mii_attach() will panic.
+ */
+#define	MII_OFFSET_ANY		-1
+#define	MII_PHY_ANY		-1
+
+/*
  * Used to attach a PHY to a parent.
  */
 struct mii_attach_args {
@@ -192,6 +206,18 @@ struct mii_media {
 #define PHY_WRITE(p, r, v) \
 	MIIBUS_WRITEREG((p)->mii_dev, (p)->mii_phy, (r), (v))
 
+enum miibus_device_ivars {
+	MIIBUS_IVAR_FLAGS
+};
+
+/*
+ * Simplified accessors for miibus
+ */
+#define	MIIBUS_ACCESSOR(var, ivar, type)				\
+	__BUS_ACCESSOR(miibus, var, MIIBUS, ivar, type)
+
+MIIBUS_ACCESSOR(flags,		FLAGS,		int)
+
 extern devclass_t	miibus_devclass;
 extern driver_t		miibus_driver;
 
@@ -199,6 +225,8 @@ int	miibus_probe(device_t);
 int	miibus_attach(device_t);
 int	miibus_detach(device_t);
 
+int	mii_attach(device_t, device_t *, struct ifnet *, ifm_change_cb_t,
+	    ifm_stat_cb_t, int, int, int, int);
 int	mii_anar(int);
 void	mii_down(struct mii_data *);
 int	mii_mediachg(struct mii_data *);