Support new MDIO hierarchy in ThunderX DTB

Some firmware revisions provide different DTB tree that include
odd MDIO placement in the tree.
This commit adds support for 2 new buses:
- MRML bridge (PCIB subordinate)
- MDIO nexus (MRML subordinate)
This allows for the correct MDIO attachment with both - new and old
firmware.

Obtained from: Semihalf
Sponsored by:  Cavium
Differential Revision: https://reviews.freebsd.org/D5070

1 files changed, 199 insertions, 5 deletions

diff --git a/sys/dev/vnic/thunder_mdio_fdt.c b/sys/dev/vnic/thunder_mdio_fdt.c
index b24be1dc3ee6..cc9415050388 100644
--- a/sys/dev/vnic/thunder_mdio_fdt.c
+++ b/sys/dev/vnic/thunder_mdio_fdt.c
@@ -38,6 +38,10 @@ __FBSDID("$FreeBSD$");
 
 #include <dev/ofw/ofw_bus.h>
 #include <dev/ofw/ofw_bus_subr.h>
+#include <dev/fdt/simplebus.h>
+
+#include <machine/bus.h>
+#include <machine/resource.h>
 
 #include "thunder_mdio_var.h"
 
@@ -60,17 +64,26 @@ static devclass_t thunder_mdio_fdt_devclass;
 
 EARLY_DRIVER_MODULE(thunder_mdio, ofwbus, thunder_mdio_fdt_driver,
     thunder_mdio_fdt_devclass, 0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
+EARLY_DRIVER_MODULE(thunder_mdio, mdionexus, thunder_mdio_fdt_driver,
+    thunder_mdio_fdt_devclass, 0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
+
+static struct ofw_compat_data mdio_compat_data[] = {
+	{"cavium,octeon-3860-mdio",	true},
+	{"cavium,thunder-8890-mdio",	true},
+	{NULL,				false}
+};
 
 static int
 thunder_mdio_fdt_probe(device_t dev)
 {
 
-	if (ofw_bus_is_compatible(dev, "cavium,octeon-3860-mdio")) {
-		device_set_desc(dev, THUNDER_MDIO_DEVSTR);
-		return (BUS_PROBE_DEFAULT);
-	}
+	if (!ofw_bus_status_okay(dev))
+		return (ENXIO);
+	if (!ofw_bus_search_compatible(dev, mdio_compat_data)->ocd_data)
+		return (ENXIO);
 
-	return (ENXIO);
+	device_set_desc(dev, THUNDER_MDIO_DEVSTR);
+	return (BUS_PROBE_DEFAULT);
 }
 
 static int
@@ -93,3 +106,184 @@ thunder_mdio_fdt_attach(device_t dev)
 
 	return (0);
 }
+
+struct mdionexus_softc {
+	struct simplebus_softc simplebus_sc;
+};
+
+static device_probe_t mdionexus_fdt_probe;
+static device_attach_t mdionexus_fdt_attach;
+
+static const struct ofw_bus_devinfo * mdionexus_ofw_get_devinfo(device_t,
+    device_t);
+
+static device_method_t mdionexus_fdt_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		mdionexus_fdt_probe),
+	DEVMETHOD(device_attach,	mdionexus_fdt_attach),
+
+	/* Bus interface */
+	DEVMETHOD(bus_alloc_resource,		bus_generic_alloc_resource),
+	DEVMETHOD(bus_release_resource,		bus_generic_release_resource),
+	DEVMETHOD(bus_activate_resource,	bus_generic_activate_resource),
+
+	/* ofw_bus interface */
+	DEVMETHOD(ofw_bus_get_devinfo,	mdionexus_ofw_get_devinfo),
+	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
+	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
+	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
+	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
+	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
+
+	DEVMETHOD_END
+};
+
+DEFINE_CLASS_0(mdionexus, mdionexus_fdt_driver, mdionexus_fdt_methods,
+    sizeof(struct mdionexus_softc));
+
+static devclass_t mdionexus_fdt_devclass;
+
+EARLY_DRIVER_MODULE(mdionexus, mrmlbus, mdionexus_fdt_driver,
+    mdionexus_fdt_devclass, 0, 0, BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
+
+static int mdionexus_ofw_fill_ranges(phandle_t, struct simplebus_softc *);
+static int mdionexus_ofw_bus_attach(device_t);
+
+static int
+mdionexus_fdt_probe(device_t dev)
+{
+
+	if (!ofw_bus_status_okay(dev))
+		return (ENXIO);
+
+	if (!ofw_bus_is_compatible(dev, "cavium,thunder-8890-mdio-nexus"))
+		return (ENXIO);
+
+	device_set_desc(dev, "Cavium ThunderX MDIO nexus");
+	return (BUS_PROBE_SPECIFIC);
+}
+
+static int
+mdionexus_fdt_attach(device_t dev)
+{
+	int err;
+
+	err = mdionexus_ofw_bus_attach(dev);
+	if (err != 0)
+		return (err);
+
+	return (bus_generic_attach(dev));
+}
+
+/* OFW bus interface */
+struct mdionexus_ofw_devinfo {
+	struct ofw_bus_devinfo	di_dinfo;
+	struct resource_list	di_rl;
+};
+
+static const struct ofw_bus_devinfo *
+mdionexus_ofw_get_devinfo(device_t bus __unused, device_t child)
+{
+	struct mdionexus_ofw_devinfo *di;
+
+	di = device_get_ivars(child);
+	return (&di->di_dinfo);
+}
+
+/* Helper functions */
+
+static int
+mdionexus_ofw_fill_ranges(phandle_t node, struct simplebus_softc *sc)
+{
+	int host_address_cells;
+	cell_t *base_ranges;
+	ssize_t nbase_ranges;
+	int err;
+	int i, j, k;
+
+	err = OF_searchencprop(OF_parent(node), "#address-cells",
+	    &host_address_cells, sizeof(host_address_cells));
+	if (err <= 0)
+		return (-1);
+
+	nbase_ranges = OF_getproplen(node, "ranges");
+	if (nbase_ranges < 0)
+		return (-1);
+	sc->nranges = nbase_ranges / sizeof(cell_t) /
+	    (sc->acells + host_address_cells + sc->scells);
+	if (sc->nranges == 0)
+		return (0);
+
+	sc->ranges = malloc(sc->nranges * sizeof(sc->ranges[0]),
+	    M_THUNDER_MDIO, M_WAITOK);
+	base_ranges = malloc(nbase_ranges, M_THUNDER_MDIO, M_WAITOK);
+	OF_getencprop(node, "ranges", base_ranges, nbase_ranges);
+
+	for (i = 0, j = 0; i < sc->nranges; i++) {
+		sc->ranges[i].bus = 0;
+		for (k = 0; k < sc->acells; k++) {
+			sc->ranges[i].bus <<= 32;
+			sc->ranges[i].bus |= base_ranges[j++];
+		}
+		sc->ranges[i].host = 0;
+		for (k = 0; k < host_address_cells; k++) {
+			sc->ranges[i].host <<= 32;
+			sc->ranges[i].host |= base_ranges[j++];
+		}
+		sc->ranges[i].size = 0;
+		for (k = 0; k < sc->scells; k++) {
+			sc->ranges[i].size <<= 32;
+			sc->ranges[i].size |= base_ranges[j++];
+		}
+	}
+
+	free(base_ranges, M_THUNDER_MDIO);
+	return (sc->nranges);
+}
+
+static int
+mdionexus_ofw_bus_attach(device_t dev)
+{
+	struct simplebus_softc *sc;
+	struct mdionexus_ofw_devinfo *di;
+	device_t child;
+	phandle_t parent, node;
+
+	parent = ofw_bus_get_node(dev);
+	simplebus_init(dev, parent);
+
+	sc = (struct simplebus_softc *)device_get_softc(dev);
+
+	if (mdionexus_ofw_fill_ranges(parent, sc) < 0) {
+		device_printf(dev, "could not get ranges\n");
+		return (ENXIO);
+	}
+	/* Iterate through all bus subordinates */
+	for (node = OF_child(parent); node > 0; node = OF_peer(node)) {
+		/* Allocate and populate devinfo. */
+		di = malloc(sizeof(*di), M_THUNDER_MDIO, M_WAITOK | M_ZERO);
+		if (ofw_bus_gen_setup_devinfo(&di->di_dinfo, node) != 0) {
+			free(di, M_THUNDER_MDIO);
+			continue;
+		}
+
+		/* Initialize and populate resource list. */
+		resource_list_init(&di->di_rl);
+		ofw_bus_reg_to_rl(dev, node, sc->acells, sc->scells,
+		    &di->di_rl);
+		ofw_bus_intr_to_rl(dev, node, &di->di_rl, NULL);
+
+		/* Add newbus device for this FDT node */
+		child = device_add_child(dev, NULL, -1);
+		if (child == NULL) {
+			resource_list_free(&di->di_rl);
+			ofw_bus_gen_destroy_devinfo(&di->di_dinfo);
+			free(di, M_THUNDER_MDIO);
+			continue;
+		}
+
+		device_set_ivars(child, di);
+	}
+
+	return (0);
+}