xref: /freebsd/sys/dev/ofw/ofw_cpu.c (revision 08637d5d1580af743f4ed6504104d038e017f918)
15cead939SRui Paulo /*-
25cead939SRui Paulo  * Copyright (C) 2009 Nathan Whitehorn
309eb425aSAndrew Turner  * Copyright (C) 2015 The FreeBSD Foundation
45cead939SRui Paulo  * All rights reserved.
55cead939SRui Paulo  *
609eb425aSAndrew Turner  * Portions of this software were developed by Andrew Turner
709eb425aSAndrew Turner  * under sponsorship from the FreeBSD Foundation.
809eb425aSAndrew Turner  *
95cead939SRui Paulo  * Redistribution and use in source and binary forms, with or without
105cead939SRui Paulo  * modification, are permitted provided that the following conditions
115cead939SRui Paulo  * are met:
125cead939SRui Paulo  * 1. Redistributions of source code must retain the above copyright
135cead939SRui Paulo  *    notice, this list of conditions and the following disclaimer.
145cead939SRui Paulo  * 2. Redistributions in binary form must reproduce the above copyright
155cead939SRui Paulo  *    notice, this list of conditions and the following disclaimer in the
165cead939SRui Paulo  *    documentation and/or other materials provided with the distribution.
175cead939SRui Paulo  *
1855629a87SEd Maste  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
1955629a87SEd Maste  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2055629a87SEd Maste  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2155629a87SEd Maste  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
2255629a87SEd Maste  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2355629a87SEd Maste  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2455629a87SEd Maste  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2555629a87SEd Maste  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2655629a87SEd Maste  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2755629a87SEd Maste  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2855629a87SEd Maste  * SUCH DAMAGE.
295cead939SRui Paulo  */
305cead939SRui Paulo 
315cead939SRui Paulo #include <sys/cdefs.h>
325cead939SRui Paulo __FBSDID("$FreeBSD$");
335cead939SRui Paulo 
345cead939SRui Paulo #include <sys/param.h>
355cead939SRui Paulo #include <sys/systm.h>
365cead939SRui Paulo #include <sys/kernel.h>
375cead939SRui Paulo #include <sys/module.h>
385cead939SRui Paulo #include <sys/malloc.h>
395cead939SRui Paulo #include <sys/bus.h>
405cead939SRui Paulo #include <sys/cpu.h>
415cead939SRui Paulo #include <machine/bus.h>
425cead939SRui Paulo 
435cead939SRui Paulo #include <dev/ofw/openfirm.h>
445cead939SRui Paulo #include <dev/ofw/ofw_bus.h>
455cead939SRui Paulo #include <dev/ofw/ofw_bus_subr.h>
4616a1c0a8SAndrew Turner #include <dev/ofw/ofw_cpu.h>
475cead939SRui Paulo 
4802398e58SEmmanuel Vadot #if defined(__arm__) || defined(__arm64__) || defined(__riscv__)
49bc9ba24fSEmmanuel Vadot #include <dev/extres/clk/clk.h>
50bc9ba24fSEmmanuel Vadot #endif
51bc9ba24fSEmmanuel Vadot 
525cead939SRui Paulo static int	ofw_cpulist_probe(device_t);
535cead939SRui Paulo static int	ofw_cpulist_attach(device_t);
545cead939SRui Paulo static const struct ofw_bus_devinfo *ofw_cpulist_get_devinfo(device_t dev,
555cead939SRui Paulo     device_t child);
565cead939SRui Paulo 
575cead939SRui Paulo static MALLOC_DEFINE(M_OFWCPU, "ofwcpu", "OFW CPU device information");
585cead939SRui Paulo 
595b86b0eaSAndrew Turner struct ofw_cpulist_softc {
605b86b0eaSAndrew Turner 	pcell_t	 sc_addr_cells;
615b86b0eaSAndrew Turner };
625b86b0eaSAndrew Turner 
635cead939SRui Paulo static device_method_t ofw_cpulist_methods[] = {
645cead939SRui Paulo 	/* Device interface */
655cead939SRui Paulo 	DEVMETHOD(device_probe,		ofw_cpulist_probe),
665cead939SRui Paulo 	DEVMETHOD(device_attach,	ofw_cpulist_attach),
675cead939SRui Paulo 
685cead939SRui Paulo 	/* Bus interface */
695cead939SRui Paulo 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
70ddfc9c4cSWarner Losh 	DEVMETHOD(bus_child_pnpinfo,	ofw_bus_gen_child_pnpinfo),
717b5d62bbSTakanori Watanabe 	DEVMETHOD(bus_get_device_path,  ofw_bus_gen_get_device_path),
725cead939SRui Paulo 
735cead939SRui Paulo 	/* ofw_bus interface */
745cead939SRui Paulo 	DEVMETHOD(ofw_bus_get_devinfo,	ofw_cpulist_get_devinfo),
755cead939SRui Paulo 	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
765cead939SRui Paulo 	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
775cead939SRui Paulo 	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
785cead939SRui Paulo 	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
795cead939SRui Paulo 	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
805cead939SRui Paulo 
815cead939SRui Paulo 	DEVMETHOD_END
825cead939SRui Paulo };
835cead939SRui Paulo 
845cead939SRui Paulo static driver_t ofw_cpulist_driver = {
855cead939SRui Paulo 	"cpulist",
865cead939SRui Paulo 	ofw_cpulist_methods,
875b86b0eaSAndrew Turner 	sizeof(struct ofw_cpulist_softc)
885cead939SRui Paulo };
895cead939SRui Paulo 
9003f6459cSJohn Baldwin DRIVER_MODULE(ofw_cpulist, ofwbus, ofw_cpulist_driver, 0, 0);
915cead939SRui Paulo 
925cead939SRui Paulo static int
935cead939SRui Paulo ofw_cpulist_probe(device_t dev)
945cead939SRui Paulo {
955cead939SRui Paulo 	const char *name;
965cead939SRui Paulo 
975cead939SRui Paulo 	name = ofw_bus_get_name(dev);
985cead939SRui Paulo 
995cead939SRui Paulo 	if (name == NULL || strcmp(name, "cpus") != 0)
1005cead939SRui Paulo 		return (ENXIO);
1015cead939SRui Paulo 
1025cead939SRui Paulo 	device_set_desc(dev, "Open Firmware CPU Group");
1035cead939SRui Paulo 
1045cead939SRui Paulo 	return (0);
1055cead939SRui Paulo }
1065cead939SRui Paulo 
1075cead939SRui Paulo static int
1085cead939SRui Paulo ofw_cpulist_attach(device_t dev)
1095cead939SRui Paulo {
1105b86b0eaSAndrew Turner 	struct ofw_cpulist_softc *sc;
1115cead939SRui Paulo 	phandle_t root, child;
1125cead939SRui Paulo 	device_t cdev;
1135cead939SRui Paulo 	struct ofw_bus_devinfo *dinfo;
1145cead939SRui Paulo 
1155b86b0eaSAndrew Turner 	sc = device_get_softc(dev);
1165cead939SRui Paulo 	root = ofw_bus_get_node(dev);
1175cead939SRui Paulo 
1185b86b0eaSAndrew Turner 	sc->sc_addr_cells = 1;
1195b86b0eaSAndrew Turner 	OF_getencprop(root, "#address-cells", &sc->sc_addr_cells,
1205b86b0eaSAndrew Turner 	    sizeof(sc->sc_addr_cells));
1215b86b0eaSAndrew Turner 
1225cead939SRui Paulo 	for (child = OF_child(root); child != 0; child = OF_peer(child)) {
1235cead939SRui Paulo 		dinfo = malloc(sizeof(*dinfo), M_OFWCPU, M_WAITOK | M_ZERO);
1245cead939SRui Paulo 
1255cead939SRui Paulo 		if (ofw_bus_gen_setup_devinfo(dinfo, child) != 0) {
1265cead939SRui Paulo 			free(dinfo, M_OFWCPU);
1275cead939SRui Paulo 			continue;
1285cead939SRui Paulo 		}
1295cead939SRui Paulo 		cdev = device_add_child(dev, NULL, -1);
1305cead939SRui Paulo 		if (cdev == NULL) {
1315cead939SRui Paulo 			device_printf(dev, "<%s>: device_add_child failed\n",
1325cead939SRui Paulo 			    dinfo->obd_name);
1335cead939SRui Paulo 			ofw_bus_gen_destroy_devinfo(dinfo);
1345cead939SRui Paulo 			free(dinfo, M_OFWCPU);
1355cead939SRui Paulo 			continue;
1365cead939SRui Paulo 		}
1375cead939SRui Paulo 		device_set_ivars(cdev, dinfo);
1385cead939SRui Paulo 	}
1395cead939SRui Paulo 
1405cead939SRui Paulo 	return (bus_generic_attach(dev));
1415cead939SRui Paulo }
1425cead939SRui Paulo 
1435cead939SRui Paulo static const struct ofw_bus_devinfo *
1445cead939SRui Paulo ofw_cpulist_get_devinfo(device_t dev, device_t child)
1455cead939SRui Paulo {
1465cead939SRui Paulo 	return (device_get_ivars(child));
1475cead939SRui Paulo }
1485cead939SRui Paulo 
1495cead939SRui Paulo static int	ofw_cpu_probe(device_t);
1505cead939SRui Paulo static int	ofw_cpu_attach(device_t);
1515cead939SRui Paulo static int	ofw_cpu_read_ivar(device_t dev, device_t child, int index,
1525cead939SRui Paulo     uintptr_t *result);
1535cead939SRui Paulo 
1545cead939SRui Paulo struct ofw_cpu_softc {
1555cead939SRui Paulo 	struct pcpu	*sc_cpu_pcpu;
1565cead939SRui Paulo 	uint32_t	 sc_nominal_mhz;
1575b86b0eaSAndrew Turner 	boolean_t	 sc_reg_valid;
1585b86b0eaSAndrew Turner 	pcell_t		 sc_reg[2];
1595cead939SRui Paulo };
1605cead939SRui Paulo 
1615cead939SRui Paulo static device_method_t ofw_cpu_methods[] = {
1625cead939SRui Paulo 	/* Device interface */
1635cead939SRui Paulo 	DEVMETHOD(device_probe,		ofw_cpu_probe),
1645cead939SRui Paulo 	DEVMETHOD(device_attach,	ofw_cpu_attach),
1655cead939SRui Paulo 
1665cead939SRui Paulo 	/* Bus interface */
1675cead939SRui Paulo 	DEVMETHOD(bus_add_child,	bus_generic_add_child),
1685cead939SRui Paulo 	DEVMETHOD(bus_read_ivar,	ofw_cpu_read_ivar),
1695cead939SRui Paulo 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
1705cead939SRui Paulo 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
1715cead939SRui Paulo 	DEVMETHOD(bus_alloc_resource,	bus_generic_alloc_resource),
1725cead939SRui Paulo 	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
1735cead939SRui Paulo 	DEVMETHOD(bus_activate_resource,bus_generic_activate_resource),
1745cead939SRui Paulo 
1755cead939SRui Paulo 	DEVMETHOD_END
1765cead939SRui Paulo };
1775cead939SRui Paulo 
1785cead939SRui Paulo static driver_t ofw_cpu_driver = {
1795cead939SRui Paulo 	"cpu",
1805cead939SRui Paulo 	ofw_cpu_methods,
1815cead939SRui Paulo 	sizeof(struct ofw_cpu_softc)
1825cead939SRui Paulo };
1835cead939SRui Paulo 
18403f6459cSJohn Baldwin DRIVER_MODULE(ofw_cpu, cpulist, ofw_cpu_driver, 0, 0);
1855cead939SRui Paulo 
1865cead939SRui Paulo static int
1875cead939SRui Paulo ofw_cpu_probe(device_t dev)
1885cead939SRui Paulo {
1895cead939SRui Paulo 	const char *type = ofw_bus_get_type(dev);
1905cead939SRui Paulo 
191cbe686f7SIan Lepore 	if (type == NULL || strcmp(type, "cpu") != 0)
1925cead939SRui Paulo 		return (ENXIO);
1935cead939SRui Paulo 
1945cead939SRui Paulo 	device_set_desc(dev, "Open Firmware CPU");
195*08637d5dSMitchell Horne 	if (!bootverbose && device_get_unit(dev) != 0) {
196*08637d5dSMitchell Horne 		device_quiet(dev);
197*08637d5dSMitchell Horne 		device_quiet_children(dev);
198*08637d5dSMitchell Horne 	}
199*08637d5dSMitchell Horne 
2005cead939SRui Paulo 	return (0);
2015cead939SRui Paulo }
2025cead939SRui Paulo 
2035cead939SRui Paulo static int
2045cead939SRui Paulo ofw_cpu_attach(device_t dev)
2055cead939SRui Paulo {
2065b86b0eaSAndrew Turner 	struct ofw_cpulist_softc *psc;
2075cead939SRui Paulo 	struct ofw_cpu_softc *sc;
208cbe686f7SIan Lepore 	phandle_t node;
2095b86b0eaSAndrew Turner 	pcell_t cell;
2105b86b0eaSAndrew Turner 	int rv;
21102398e58SEmmanuel Vadot #if defined(__arm__) || defined(__arm64__) || defined(__riscv__)
212bc9ba24fSEmmanuel Vadot 	clk_t cpuclk;
213bc9ba24fSEmmanuel Vadot 	uint64_t freq;
214bc9ba24fSEmmanuel Vadot #endif
2155cead939SRui Paulo 
2165cead939SRui Paulo 	sc = device_get_softc(dev);
2175b86b0eaSAndrew Turner 	psc = device_get_softc(device_get_parent(dev));
2185b86b0eaSAndrew Turner 
2195b86b0eaSAndrew Turner 	if (nitems(sc->sc_reg) < psc->sc_addr_cells) {
2205b86b0eaSAndrew Turner 		if (bootverbose)
2215b86b0eaSAndrew Turner 			device_printf(dev, "Too many address cells\n");
2225b86b0eaSAndrew Turner 		return (EINVAL);
223cbe686f7SIan Lepore 	}
2245b86b0eaSAndrew Turner 
2255b86b0eaSAndrew Turner 	node = ofw_bus_get_node(dev);
2265b86b0eaSAndrew Turner 
2275b86b0eaSAndrew Turner 	/* Read and validate the reg property for use later */
2285b86b0eaSAndrew Turner 	sc->sc_reg_valid = false;
2295b86b0eaSAndrew Turner 	rv = OF_getencprop(node, "reg", sc->sc_reg, sizeof(sc->sc_reg));
2305b86b0eaSAndrew Turner 	if (rv < 0)
2315b86b0eaSAndrew Turner 		device_printf(dev, "missing 'reg' property\n");
2325b86b0eaSAndrew Turner 	else if ((rv % 4) != 0) {
2335b86b0eaSAndrew Turner 		if (bootverbose)
2345b86b0eaSAndrew Turner 			device_printf(dev, "Malformed reg property\n");
2355b86b0eaSAndrew Turner 	} else if ((rv / 4) != psc->sc_addr_cells) {
2365b86b0eaSAndrew Turner 		if (bootverbose)
2375b86b0eaSAndrew Turner 			device_printf(dev, "Invalid reg size %u\n", rv);
2385b86b0eaSAndrew Turner 	} else
2395b86b0eaSAndrew Turner 		sc->sc_reg_valid = true;
2405b86b0eaSAndrew Turner 
241d23d5d73SJustin Hibbits #ifdef __powerpc__
242d23d5d73SJustin Hibbits 	/*
243d23d5d73SJustin Hibbits 	 * On powerpc, "interrupt-servers" denotes a SMT CPU.  Look for any
244d23d5d73SJustin Hibbits 	 * thread on this CPU, and assign that.
245d23d5d73SJustin Hibbits 	 */
246d23d5d73SJustin Hibbits 	if (OF_hasprop(node, "ibm,ppc-interrupt-server#s")) {
247d23d5d73SJustin Hibbits 		struct cpuref cpuref;
248d23d5d73SJustin Hibbits 		cell_t *servers;
249d23d5d73SJustin Hibbits 		int i, nservers, rv;
250d23d5d73SJustin Hibbits 
251d23d5d73SJustin Hibbits 		if ((nservers = OF_getencprop_alloc(node,
252d23d5d73SJustin Hibbits 		    "ibm,ppc-interrupt-server#s", (void **)&servers)) < 0)
253d23d5d73SJustin Hibbits 			return (ENXIO);
254d23d5d73SJustin Hibbits 		nservers /= sizeof(cell_t);
255d23d5d73SJustin Hibbits 		for (i = 0; i < nservers; i++) {
256d23d5d73SJustin Hibbits 			for (rv = platform_smp_first_cpu(&cpuref); rv == 0;
257d23d5d73SJustin Hibbits 			    rv = platform_smp_next_cpu(&cpuref)) {
258d23d5d73SJustin Hibbits 				if (cpuref.cr_hwref == servers[i]) {
259d23d5d73SJustin Hibbits 					sc->sc_cpu_pcpu =
260d23d5d73SJustin Hibbits 					    pcpu_find(cpuref.cr_cpuid);
261d23d5d73SJustin Hibbits 					if (sc->sc_cpu_pcpu == NULL) {
262d23d5d73SJustin Hibbits 						OF_prop_free(servers);
263d23d5d73SJustin Hibbits 						return (ENXIO);
264d23d5d73SJustin Hibbits 					}
265d23d5d73SJustin Hibbits 					break;
266d23d5d73SJustin Hibbits 				}
267d23d5d73SJustin Hibbits 			}
268d23d5d73SJustin Hibbits 			if (rv != ENOENT)
269d23d5d73SJustin Hibbits 				break;
270d23d5d73SJustin Hibbits 		}
271d23d5d73SJustin Hibbits 		OF_prop_free(servers);
272d23d5d73SJustin Hibbits 		if (sc->sc_cpu_pcpu == NULL) {
273d23d5d73SJustin Hibbits 			device_printf(dev, "No CPU found for this device.\n");
274d23d5d73SJustin Hibbits 			return (ENXIO);
275d23d5d73SJustin Hibbits 		}
276d23d5d73SJustin Hibbits 	} else
277d23d5d73SJustin Hibbits #endif
2785b86b0eaSAndrew Turner 	sc->sc_cpu_pcpu = pcpu_find(device_get_unit(dev));
2795b86b0eaSAndrew Turner 
280cbe686f7SIan Lepore 	if (OF_getencprop(node, "clock-frequency", &cell, sizeof(cell)) < 0) {
28102398e58SEmmanuel Vadot #if defined(__arm__) || defined(__arm64__) || defined(__riscv__)
282bc9ba24fSEmmanuel Vadot 		rv = clk_get_by_ofw_index(dev, 0, 0, &cpuclk);
283bc9ba24fSEmmanuel Vadot 		if (rv == 0) {
284bc9ba24fSEmmanuel Vadot 			rv = clk_get_freq(cpuclk, &freq);
285bc9ba24fSEmmanuel Vadot 			if (rv != 0 && bootverbose)
286bc9ba24fSEmmanuel Vadot 				device_printf(dev,
287bc9ba24fSEmmanuel Vadot 				    "Cannot get freq of property clocks\n");
288bc9ba24fSEmmanuel Vadot 			else
289bc9ba24fSEmmanuel Vadot 				sc->sc_nominal_mhz = freq / 1000000;
290bc9ba24fSEmmanuel Vadot 		} else
291bc9ba24fSEmmanuel Vadot #endif
292bc9ba24fSEmmanuel Vadot 		{
29309eb425aSAndrew Turner 			if (bootverbose)
29409eb425aSAndrew Turner 				device_printf(dev,
29509eb425aSAndrew Turner 				    "missing 'clock-frequency' property\n");
296bc9ba24fSEmmanuel Vadot 		}
29709eb425aSAndrew Turner 	} else
2985cead939SRui Paulo 		sc->sc_nominal_mhz = cell / 1000000; /* convert to MHz */
2995cead939SRui Paulo 
300bc9ba24fSEmmanuel Vadot 	if (sc->sc_nominal_mhz != 0 && bootverbose)
301bc9ba24fSEmmanuel Vadot 		device_printf(dev, "Nominal frequency %dMhz\n",
302bc9ba24fSEmmanuel Vadot 		    sc->sc_nominal_mhz);
3035cead939SRui Paulo 	bus_generic_probe(dev);
3045cead939SRui Paulo 	return (bus_generic_attach(dev));
3055cead939SRui Paulo }
3065cead939SRui Paulo 
3075cead939SRui Paulo static int
3085cead939SRui Paulo ofw_cpu_read_ivar(device_t dev, device_t child, int index, uintptr_t *result)
3095cead939SRui Paulo {
310deb77283SAndrew Turner 	struct ofw_cpulist_softc *psc;
3115cead939SRui Paulo 	struct ofw_cpu_softc *sc;
3125cead939SRui Paulo 
3135cead939SRui Paulo 	sc = device_get_softc(dev);
3145cead939SRui Paulo 
3155cead939SRui Paulo 	switch (index) {
3165cead939SRui Paulo 	case CPU_IVAR_PCPU:
3175cead939SRui Paulo 		*result = (uintptr_t)sc->sc_cpu_pcpu;
3185cead939SRui Paulo 		return (0);
3195cead939SRui Paulo 	case CPU_IVAR_NOMINAL_MHZ:
32009eb425aSAndrew Turner 		if (sc->sc_nominal_mhz > 0) {
3215cead939SRui Paulo 			*result = (uintptr_t)sc->sc_nominal_mhz;
3225cead939SRui Paulo 			return (0);
3235cead939SRui Paulo 		}
32409eb425aSAndrew Turner 		break;
325deb77283SAndrew Turner 	case CPU_IVAR_CPUID_SIZE:
326deb77283SAndrew Turner 		psc = device_get_softc(device_get_parent(dev));
327deb77283SAndrew Turner 		*result = psc->sc_addr_cells;
328deb77283SAndrew Turner 		return (0);
329deb77283SAndrew Turner 	case CPU_IVAR_CPUID:
330deb77283SAndrew Turner 		if (sc->sc_reg_valid) {
331deb77283SAndrew Turner 			*result = (uintptr_t)sc->sc_reg;
332deb77283SAndrew Turner 			return (0);
333deb77283SAndrew Turner 		}
334deb77283SAndrew Turner 		break;
33509eb425aSAndrew Turner 	}
3365cead939SRui Paulo 
3375cead939SRui Paulo 	return (ENOENT);
3385cead939SRui Paulo }
3395cead939SRui Paulo 
34016a1c0a8SAndrew Turner int
34116a1c0a8SAndrew Turner ofw_cpu_early_foreach(ofw_cpu_foreach_cb callback, boolean_t only_runnable)
34216a1c0a8SAndrew Turner {
34316a1c0a8SAndrew Turner 	phandle_t node, child;
34416a1c0a8SAndrew Turner 	pcell_t addr_cells, reg[2];
34516a1c0a8SAndrew Turner 	char status[16];
3468b21d6aeSZbigniew Bodek 	char device_type[16];
3478b21d6aeSZbigniew Bodek 	u_int id, next_id;
34816a1c0a8SAndrew Turner 	int count, rv;
34916a1c0a8SAndrew Turner 
35016a1c0a8SAndrew Turner 	count = 0;
35116a1c0a8SAndrew Turner 	id = 0;
3528b21d6aeSZbigniew Bodek 	next_id = 0;
35316a1c0a8SAndrew Turner 
35416a1c0a8SAndrew Turner 	node = OF_finddevice("/cpus");
35516a1c0a8SAndrew Turner 	if (node == -1)
35616a1c0a8SAndrew Turner 		return (-1);
35716a1c0a8SAndrew Turner 
35816a1c0a8SAndrew Turner 	/* Find the number of cells in the cpu register */
35916a1c0a8SAndrew Turner 	if (OF_getencprop(node, "#address-cells", &addr_cells,
36016a1c0a8SAndrew Turner 	    sizeof(addr_cells)) < 0)
36116a1c0a8SAndrew Turner 		return (-1);
36216a1c0a8SAndrew Turner 
3638b21d6aeSZbigniew Bodek 	for (child = OF_child(node); child != 0; child = OF_peer(child),
3648b21d6aeSZbigniew Bodek 	    id = next_id) {
3658b21d6aeSZbigniew Bodek 		/* Check if child is a CPU */
3668b21d6aeSZbigniew Bodek 		memset(device_type, 0, sizeof(device_type));
3678b21d6aeSZbigniew Bodek 		rv = OF_getprop(child, "device_type", device_type,
3688b21d6aeSZbigniew Bodek 		    sizeof(device_type) - 1);
3698b21d6aeSZbigniew Bodek 		if (rv < 0)
3708b21d6aeSZbigniew Bodek 			continue;
3718b21d6aeSZbigniew Bodek 		if (strcmp(device_type, "cpu") != 0)
3728b21d6aeSZbigniew Bodek 			continue;
3738b21d6aeSZbigniew Bodek 
3748b21d6aeSZbigniew Bodek 		/* We're processing CPU, update next_id used in the next iteration */
3758b21d6aeSZbigniew Bodek 		next_id++;
3768b21d6aeSZbigniew Bodek 
37716a1c0a8SAndrew Turner 		/*
37816a1c0a8SAndrew Turner 		 * If we are filtering by runnable then limit to only
3795d840968SOlivier Houchard 		 * those that have been enabled, or do provide a method
3805d840968SOlivier Houchard 		 * to enable them.
38116a1c0a8SAndrew Turner 		 */
38216a1c0a8SAndrew Turner 		if (only_runnable) {
38316a1c0a8SAndrew Turner 			status[0] = '\0';
38416a1c0a8SAndrew Turner 			OF_getprop(child, "status", status, sizeof(status));
38521ce594eSOlivier Houchard 			if (status[0] != '\0' && strcmp(status, "okay") != 0 &&
38621ce594eSOlivier Houchard 				strcmp(status, "ok") != 0 &&
38721ce594eSOlivier Houchard 				!OF_hasprop(child, "enable-method"))
38816a1c0a8SAndrew Turner 					continue;
38916a1c0a8SAndrew Turner 		}
39016a1c0a8SAndrew Turner 
39116a1c0a8SAndrew Turner 		/*
39216a1c0a8SAndrew Turner 		 * Check we have a register to identify the cpu
39316a1c0a8SAndrew Turner 		 */
39416a1c0a8SAndrew Turner 		rv = OF_getencprop(child, "reg", reg,
39516a1c0a8SAndrew Turner 		    addr_cells * sizeof(cell_t));
39616a1c0a8SAndrew Turner 		if (rv != addr_cells * sizeof(cell_t))
39716a1c0a8SAndrew Turner 			continue;
39816a1c0a8SAndrew Turner 
39916a1c0a8SAndrew Turner 		if (callback == NULL || callback(id, child, addr_cells, reg))
40016a1c0a8SAndrew Turner 			count++;
40116a1c0a8SAndrew Turner 	}
40216a1c0a8SAndrew Turner 
40316a1c0a8SAndrew Turner 	return (only_runnable ? count : id);
40416a1c0a8SAndrew Turner }
405