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v4.17
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/string.h>
  3#include <linux/kernel.h>
  4#include <linux/of.h>
  5#include <linux/init.h>
  6#include <linux/mod_devicetable.h>
  7#include <linux/slab.h>
  8#include <linux/errno.h>
  9#include <linux/irq.h>
 10#include <linux/of_device.h>
 11#include <linux/of_platform.h>
 
 12#include <asm/leon.h>
 13#include <asm/leon_amba.h>
 14
 15#include "of_device_common.h"
 16#include "irq.h"
 17
 18/*
 19 * PCI bus specific translator
 20 */
 21
 22static int of_bus_pci_match(struct device_node *np)
 23{
 24	if (!strcmp(np->type, "pci") || !strcmp(np->type, "pciex")) {
 25		/* Do not do PCI specific frobbing if the
 26		 * PCI bridge lacks a ranges property.  We
 27		 * want to pass it through up to the next
 28		 * parent as-is, not with the PCI translate
 29		 * method which chops off the top address cell.
 30		 */
 31		if (!of_find_property(np, "ranges", NULL))
 32			return 0;
 33
 34		return 1;
 35	}
 36
 37	return 0;
 38}
 39
 40static void of_bus_pci_count_cells(struct device_node *np,
 41				   int *addrc, int *sizec)
 42{
 43	if (addrc)
 44		*addrc = 3;
 45	if (sizec)
 46		*sizec = 2;
 47}
 48
 49static int of_bus_pci_map(u32 *addr, const u32 *range,
 50			  int na, int ns, int pna)
 51{
 52	u32 result[OF_MAX_ADDR_CELLS];
 53	int i;
 54
 55	/* Check address type match */
 56	if ((addr[0] ^ range[0]) & 0x03000000)
 57		return -EINVAL;
 58
 59	if (of_out_of_range(addr + 1, range + 1, range + na + pna,
 60			    na - 1, ns))
 61		return -EINVAL;
 62
 63	/* Start with the parent range base.  */
 64	memcpy(result, range + na, pna * 4);
 65
 66	/* Add in the child address offset, skipping high cell.  */
 67	for (i = 0; i < na - 1; i++)
 68		result[pna - 1 - i] +=
 69			(addr[na - 1 - i] -
 70			 range[na - 1 - i]);
 71
 72	memcpy(addr, result, pna * 4);
 73
 74	return 0;
 75}
 76
 77static unsigned long of_bus_pci_get_flags(const u32 *addr, unsigned long flags)
 78{
 79	u32 w = addr[0];
 80
 81	/* For PCI, we override whatever child busses may have used.  */
 82	flags = 0;
 83	switch((w >> 24) & 0x03) {
 84	case 0x01:
 85		flags |= IORESOURCE_IO;
 86		break;
 87
 88	case 0x02: /* 32 bits */
 89	case 0x03: /* 64 bits */
 90		flags |= IORESOURCE_MEM;
 91		break;
 92	}
 93	if (w & 0x40000000)
 94		flags |= IORESOURCE_PREFETCH;
 95	return flags;
 96}
 97
 98static unsigned long of_bus_sbus_get_flags(const u32 *addr, unsigned long flags)
 99{
100	return IORESOURCE_MEM;
101}
102
103 /*
104 * AMBAPP bus specific translator
105 */
106
107static int of_bus_ambapp_match(struct device_node *np)
108{
109	return !strcmp(np->type, "ambapp");
110}
111
112static void of_bus_ambapp_count_cells(struct device_node *child,
113				      int *addrc, int *sizec)
114{
115	if (addrc)
116		*addrc = 1;
117	if (sizec)
118		*sizec = 1;
119}
120
121static int of_bus_ambapp_map(u32 *addr, const u32 *range,
122			     int na, int ns, int pna)
123{
124	return of_bus_default_map(addr, range, na, ns, pna);
125}
126
127static unsigned long of_bus_ambapp_get_flags(const u32 *addr,
128					     unsigned long flags)
129{
130	return IORESOURCE_MEM;
131}
132
133/*
134 * Array of bus specific translators
135 */
136
137static struct of_bus of_busses[] = {
138	/* PCI */
139	{
140		.name = "pci",
141		.addr_prop_name = "assigned-addresses",
142		.match = of_bus_pci_match,
143		.count_cells = of_bus_pci_count_cells,
144		.map = of_bus_pci_map,
145		.get_flags = of_bus_pci_get_flags,
146	},
147	/* SBUS */
148	{
149		.name = "sbus",
150		.addr_prop_name = "reg",
151		.match = of_bus_sbus_match,
152		.count_cells = of_bus_sbus_count_cells,
153		.map = of_bus_default_map,
154		.get_flags = of_bus_sbus_get_flags,
155	},
156	/* AMBA */
157	{
158		.name = "ambapp",
159		.addr_prop_name = "reg",
160		.match = of_bus_ambapp_match,
161		.count_cells = of_bus_ambapp_count_cells,
162		.map = of_bus_ambapp_map,
163		.get_flags = of_bus_ambapp_get_flags,
164	},
165	/* Default */
166	{
167		.name = "default",
168		.addr_prop_name = "reg",
169		.match = NULL,
170		.count_cells = of_bus_default_count_cells,
171		.map = of_bus_default_map,
172		.get_flags = of_bus_default_get_flags,
173	},
174};
175
176static struct of_bus *of_match_bus(struct device_node *np)
177{
178	int i;
179
180	for (i = 0; i < ARRAY_SIZE(of_busses); i ++)
181		if (!of_busses[i].match || of_busses[i].match(np))
182			return &of_busses[i];
183	BUG();
184	return NULL;
185}
186
187static int __init build_one_resource(struct device_node *parent,
188				     struct of_bus *bus,
189				     struct of_bus *pbus,
190				     u32 *addr,
191				     int na, int ns, int pna)
192{
193	const u32 *ranges;
194	unsigned int rlen;
195	int rone;
196
197	ranges = of_get_property(parent, "ranges", &rlen);
198	if (ranges == NULL || rlen == 0) {
199		u32 result[OF_MAX_ADDR_CELLS];
200		int i;
201
202		memset(result, 0, pna * 4);
203		for (i = 0; i < na; i++)
204			result[pna - 1 - i] =
205				addr[na - 1 - i];
206
207		memcpy(addr, result, pna * 4);
208		return 0;
209	}
210
211	/* Now walk through the ranges */
212	rlen /= 4;
213	rone = na + pna + ns;
214	for (; rlen >= rone; rlen -= rone, ranges += rone) {
215		if (!bus->map(addr, ranges, na, ns, pna))
216			return 0;
217	}
218
219	return 1;
220}
221
222static int __init use_1to1_mapping(struct device_node *pp)
223{
224	/* If we have a ranges property in the parent, use it.  */
225	if (of_find_property(pp, "ranges", NULL) != NULL)
226		return 0;
227
228	/* Some SBUS devices use intermediate nodes to express
229	 * hierarchy within the device itself.  These aren't
230	 * real bus nodes, and don't have a 'ranges' property.
231	 * But, we should still pass the translation work up
232	 * to the SBUS itself.
233	 */
234	if (!strcmp(pp->name, "dma") ||
235	    !strcmp(pp->name, "espdma") ||
236	    !strcmp(pp->name, "ledma") ||
237	    !strcmp(pp->name, "lebuffer"))
238		return 0;
239
240	return 1;
241}
242
243static int of_resource_verbose;
244
245static void __init build_device_resources(struct platform_device *op,
246					  struct device *parent)
247{
248	struct platform_device *p_op;
249	struct of_bus *bus;
250	int na, ns;
251	int index, num_reg;
252	const void *preg;
253
254	if (!parent)
255		return;
256
257	p_op = to_platform_device(parent);
258	bus = of_match_bus(p_op->dev.of_node);
259	bus->count_cells(op->dev.of_node, &na, &ns);
260
261	preg = of_get_property(op->dev.of_node, bus->addr_prop_name, &num_reg);
262	if (!preg || num_reg == 0)
263		return;
264
265	/* Convert to num-cells.  */
266	num_reg /= 4;
267
268	/* Conver to num-entries.  */
269	num_reg /= na + ns;
270
271	op->resource = op->archdata.resource;
272	op->num_resources = num_reg;
273	for (index = 0; index < num_reg; index++) {
274		struct resource *r = &op->resource[index];
275		u32 addr[OF_MAX_ADDR_CELLS];
276		const u32 *reg = (preg + (index * ((na + ns) * 4)));
277		struct device_node *dp = op->dev.of_node;
278		struct device_node *pp = p_op->dev.of_node;
279		struct of_bus *pbus, *dbus;
280		u64 size, result = OF_BAD_ADDR;
281		unsigned long flags;
282		int dna, dns;
283		int pna, pns;
284
285		size = of_read_addr(reg + na, ns);
286
287		memcpy(addr, reg, na * 4);
288
289		flags = bus->get_flags(reg, 0);
290
291		if (use_1to1_mapping(pp)) {
292			result = of_read_addr(addr, na);
293			goto build_res;
294		}
295
296		dna = na;
297		dns = ns;
298		dbus = bus;
299
300		while (1) {
301			dp = pp;
302			pp = dp->parent;
303			if (!pp) {
304				result = of_read_addr(addr, dna);
305				break;
306			}
307
308			pbus = of_match_bus(pp);
309			pbus->count_cells(dp, &pna, &pns);
310
311			if (build_one_resource(dp, dbus, pbus, addr,
312					       dna, dns, pna))
313				break;
314
315			flags = pbus->get_flags(addr, flags);
316
317			dna = pna;
318			dns = pns;
319			dbus = pbus;
320		}
321
322	build_res:
323		memset(r, 0, sizeof(*r));
324
325		if (of_resource_verbose)
326			printk("%s reg[%d] -> %llx\n",
327			       op->dev.of_node->full_name, index,
328			       result);
329
330		if (result != OF_BAD_ADDR) {
331			r->start = result & 0xffffffff;
332			r->end = result + size - 1;
333			r->flags = flags | ((result >> 32ULL) & 0xffUL);
334		}
335		r->name = op->dev.of_node->name;
336	}
337}
338
339static struct platform_device * __init scan_one_device(struct device_node *dp,
340						 struct device *parent)
341{
342	struct platform_device *op = kzalloc(sizeof(*op), GFP_KERNEL);
343	const struct linux_prom_irqs *intr;
344	struct dev_archdata *sd;
345	int len, i;
346
347	if (!op)
348		return NULL;
349
350	sd = &op->dev.archdata;
351	sd->op = op;
352
353	op->dev.of_node = dp;
354
355	intr = of_get_property(dp, "intr", &len);
356	if (intr) {
357		op->archdata.num_irqs = len / sizeof(struct linux_prom_irqs);
358		for (i = 0; i < op->archdata.num_irqs; i++)
359			op->archdata.irqs[i] =
360			    sparc_config.build_device_irq(op, intr[i].pri);
361	} else {
362		const unsigned int *irq =
363			of_get_property(dp, "interrupts", &len);
364
365		if (irq) {
366			op->archdata.num_irqs = len / sizeof(unsigned int);
367			for (i = 0; i < op->archdata.num_irqs; i++)
368				op->archdata.irqs[i] =
369				    sparc_config.build_device_irq(op, irq[i]);
370		} else {
371			op->archdata.num_irqs = 0;
372		}
373	}
374
375	build_device_resources(op, parent);
376
377	op->dev.parent = parent;
378	op->dev.bus = &platform_bus_type;
379	if (!parent)
380		dev_set_name(&op->dev, "root");
381	else
382		dev_set_name(&op->dev, "%08x", dp->phandle);
383
 
 
 
384	if (of_device_register(op)) {
385		printk("%s: Could not register of device.\n",
386		       dp->full_name);
387		kfree(op);
388		op = NULL;
389	}
390
391	return op;
392}
393
394static void __init scan_tree(struct device_node *dp, struct device *parent)
395{
396	while (dp) {
397		struct platform_device *op = scan_one_device(dp, parent);
398
399		if (op)
400			scan_tree(dp->child, &op->dev);
401
402		dp = dp->sibling;
403	}
404}
405
406static int __init scan_of_devices(void)
407{
408	struct device_node *root = of_find_node_by_path("/");
409	struct platform_device *parent;
410
411	parent = scan_one_device(root, NULL);
412	if (!parent)
413		return 0;
414
415	scan_tree(root->child, &parent->dev);
416	return 0;
417}
418postcore_initcall(scan_of_devices);
419
420static int __init of_debug(char *str)
421{
422	int val = 0;
423
424	get_option(&str, &val);
425	if (val & 1)
426		of_resource_verbose = 1;
427	return 1;
428}
429
430__setup("of_debug=", of_debug);
v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/string.h>
  3#include <linux/kernel.h>
  4#include <linux/of.h>
  5#include <linux/init.h>
  6#include <linux/mod_devicetable.h>
  7#include <linux/slab.h>
  8#include <linux/errno.h>
  9#include <linux/irq.h>
 10#include <linux/of_device.h>
 11#include <linux/of_platform.h>
 12#include <linux/dma-mapping.h>
 13#include <asm/leon.h>
 14#include <asm/leon_amba.h>
 15
 16#include "of_device_common.h"
 17#include "irq.h"
 18
 19/*
 20 * PCI bus specific translator
 21 */
 22
 23static int of_bus_pci_match(struct device_node *np)
 24{
 25	if (of_node_is_type(np, "pci") || of_node_is_type(np, "pciex")) {
 26		/* Do not do PCI specific frobbing if the
 27		 * PCI bridge lacks a ranges property.  We
 28		 * want to pass it through up to the next
 29		 * parent as-is, not with the PCI translate
 30		 * method which chops off the top address cell.
 31		 */
 32		if (!of_find_property(np, "ranges", NULL))
 33			return 0;
 34
 35		return 1;
 36	}
 37
 38	return 0;
 39}
 40
 41static void of_bus_pci_count_cells(struct device_node *np,
 42				   int *addrc, int *sizec)
 43{
 44	if (addrc)
 45		*addrc = 3;
 46	if (sizec)
 47		*sizec = 2;
 48}
 49
 50static int of_bus_pci_map(u32 *addr, const u32 *range,
 51			  int na, int ns, int pna)
 52{
 53	u32 result[OF_MAX_ADDR_CELLS];
 54	int i;
 55
 56	/* Check address type match */
 57	if ((addr[0] ^ range[0]) & 0x03000000)
 58		return -EINVAL;
 59
 60	if (of_out_of_range(addr + 1, range + 1, range + na + pna,
 61			    na - 1, ns))
 62		return -EINVAL;
 63
 64	/* Start with the parent range base.  */
 65	memcpy(result, range + na, pna * 4);
 66
 67	/* Add in the child address offset, skipping high cell.  */
 68	for (i = 0; i < na - 1; i++)
 69		result[pna - 1 - i] +=
 70			(addr[na - 1 - i] -
 71			 range[na - 1 - i]);
 72
 73	memcpy(addr, result, pna * 4);
 74
 75	return 0;
 76}
 77
 78static unsigned long of_bus_pci_get_flags(const u32 *addr, unsigned long flags)
 79{
 80	u32 w = addr[0];
 81
 82	/* For PCI, we override whatever child busses may have used.  */
 83	flags = 0;
 84	switch((w >> 24) & 0x03) {
 85	case 0x01:
 86		flags |= IORESOURCE_IO;
 87		break;
 88
 89	case 0x02: /* 32 bits */
 90	case 0x03: /* 64 bits */
 91		flags |= IORESOURCE_MEM;
 92		break;
 93	}
 94	if (w & 0x40000000)
 95		flags |= IORESOURCE_PREFETCH;
 96	return flags;
 97}
 98
 99static unsigned long of_bus_sbus_get_flags(const u32 *addr, unsigned long flags)
100{
101	return IORESOURCE_MEM;
102}
103
104 /*
105 * AMBAPP bus specific translator
106 */
107
108static int of_bus_ambapp_match(struct device_node *np)
109{
110	return of_node_is_type(np, "ambapp");
111}
112
113static void of_bus_ambapp_count_cells(struct device_node *child,
114				      int *addrc, int *sizec)
115{
116	if (addrc)
117		*addrc = 1;
118	if (sizec)
119		*sizec = 1;
120}
121
122static int of_bus_ambapp_map(u32 *addr, const u32 *range,
123			     int na, int ns, int pna)
124{
125	return of_bus_default_map(addr, range, na, ns, pna);
126}
127
128static unsigned long of_bus_ambapp_get_flags(const u32 *addr,
129					     unsigned long flags)
130{
131	return IORESOURCE_MEM;
132}
133
134/*
135 * Array of bus specific translators
136 */
137
138static struct of_bus of_busses[] = {
139	/* PCI */
140	{
141		.name = "pci",
142		.addr_prop_name = "assigned-addresses",
143		.match = of_bus_pci_match,
144		.count_cells = of_bus_pci_count_cells,
145		.map = of_bus_pci_map,
146		.get_flags = of_bus_pci_get_flags,
147	},
148	/* SBUS */
149	{
150		.name = "sbus",
151		.addr_prop_name = "reg",
152		.match = of_bus_sbus_match,
153		.count_cells = of_bus_sbus_count_cells,
154		.map = of_bus_default_map,
155		.get_flags = of_bus_sbus_get_flags,
156	},
157	/* AMBA */
158	{
159		.name = "ambapp",
160		.addr_prop_name = "reg",
161		.match = of_bus_ambapp_match,
162		.count_cells = of_bus_ambapp_count_cells,
163		.map = of_bus_ambapp_map,
164		.get_flags = of_bus_ambapp_get_flags,
165	},
166	/* Default */
167	{
168		.name = "default",
169		.addr_prop_name = "reg",
170		.match = NULL,
171		.count_cells = of_bus_default_count_cells,
172		.map = of_bus_default_map,
173		.get_flags = of_bus_default_get_flags,
174	},
175};
176
177static struct of_bus *of_match_bus(struct device_node *np)
178{
179	int i;
180
181	for (i = 0; i < ARRAY_SIZE(of_busses); i ++)
182		if (!of_busses[i].match || of_busses[i].match(np))
183			return &of_busses[i];
184	BUG();
185	return NULL;
186}
187
188static int __init build_one_resource(struct device_node *parent,
189				     struct of_bus *bus,
190				     struct of_bus *pbus,
191				     u32 *addr,
192				     int na, int ns, int pna)
193{
194	const u32 *ranges;
195	unsigned int rlen;
196	int rone;
197
198	ranges = of_get_property(parent, "ranges", &rlen);
199	if (ranges == NULL || rlen == 0) {
200		u32 result[OF_MAX_ADDR_CELLS];
201		int i;
202
203		memset(result, 0, pna * 4);
204		for (i = 0; i < na; i++)
205			result[pna - 1 - i] =
206				addr[na - 1 - i];
207
208		memcpy(addr, result, pna * 4);
209		return 0;
210	}
211
212	/* Now walk through the ranges */
213	rlen /= 4;
214	rone = na + pna + ns;
215	for (; rlen >= rone; rlen -= rone, ranges += rone) {
216		if (!bus->map(addr, ranges, na, ns, pna))
217			return 0;
218	}
219
220	return 1;
221}
222
223static int __init use_1to1_mapping(struct device_node *pp)
224{
225	/* If we have a ranges property in the parent, use it.  */
226	if (of_find_property(pp, "ranges", NULL) != NULL)
227		return 0;
228
229	/* Some SBUS devices use intermediate nodes to express
230	 * hierarchy within the device itself.  These aren't
231	 * real bus nodes, and don't have a 'ranges' property.
232	 * But, we should still pass the translation work up
233	 * to the SBUS itself.
234	 */
235	if (of_node_name_eq(pp, "dma") ||
236	    of_node_name_eq(pp, "espdma") ||
237	    of_node_name_eq(pp, "ledma") ||
238	    of_node_name_eq(pp, "lebuffer"))
239		return 0;
240
241	return 1;
242}
243
244static int of_resource_verbose;
245
246static void __init build_device_resources(struct platform_device *op,
247					  struct device *parent)
248{
249	struct platform_device *p_op;
250	struct of_bus *bus;
251	int na, ns;
252	int index, num_reg;
253	const void *preg;
254
255	if (!parent)
256		return;
257
258	p_op = to_platform_device(parent);
259	bus = of_match_bus(p_op->dev.of_node);
260	bus->count_cells(op->dev.of_node, &na, &ns);
261
262	preg = of_get_property(op->dev.of_node, bus->addr_prop_name, &num_reg);
263	if (!preg || num_reg == 0)
264		return;
265
266	/* Convert to num-cells.  */
267	num_reg /= 4;
268
269	/* Conver to num-entries.  */
270	num_reg /= na + ns;
271
272	op->resource = op->archdata.resource;
273	op->num_resources = num_reg;
274	for (index = 0; index < num_reg; index++) {
275		struct resource *r = &op->resource[index];
276		u32 addr[OF_MAX_ADDR_CELLS];
277		const u32 *reg = (preg + (index * ((na + ns) * 4)));
278		struct device_node *dp = op->dev.of_node;
279		struct device_node *pp = p_op->dev.of_node;
280		struct of_bus *pbus, *dbus;
281		u64 size, result = OF_BAD_ADDR;
282		unsigned long flags;
283		int dna, dns;
284		int pna, pns;
285
286		size = of_read_addr(reg + na, ns);
287
288		memcpy(addr, reg, na * 4);
289
290		flags = bus->get_flags(reg, 0);
291
292		if (use_1to1_mapping(pp)) {
293			result = of_read_addr(addr, na);
294			goto build_res;
295		}
296
297		dna = na;
298		dns = ns;
299		dbus = bus;
300
301		while (1) {
302			dp = pp;
303			pp = dp->parent;
304			if (!pp) {
305				result = of_read_addr(addr, dna);
306				break;
307			}
308
309			pbus = of_match_bus(pp);
310			pbus->count_cells(dp, &pna, &pns);
311
312			if (build_one_resource(dp, dbus, pbus, addr,
313					       dna, dns, pna))
314				break;
315
316			flags = pbus->get_flags(addr, flags);
317
318			dna = pna;
319			dns = pns;
320			dbus = pbus;
321		}
322
323	build_res:
324		memset(r, 0, sizeof(*r));
325
326		if (of_resource_verbose)
327			printk("%pOF reg[%d] -> %llx\n",
328			       op->dev.of_node, index,
329			       result);
330
331		if (result != OF_BAD_ADDR) {
332			r->start = result & 0xffffffff;
333			r->end = result + size - 1;
334			r->flags = flags | ((result >> 32ULL) & 0xffUL);
335		}
336		r->name = op->dev.of_node->full_name;
337	}
338}
339
340static struct platform_device * __init scan_one_device(struct device_node *dp,
341						 struct device *parent)
342{
343	struct platform_device *op = kzalloc(sizeof(*op), GFP_KERNEL);
344	const struct linux_prom_irqs *intr;
345	struct dev_archdata *sd;
346	int len, i;
347
348	if (!op)
349		return NULL;
350
351	sd = &op->dev.archdata;
352	sd->op = op;
353
354	op->dev.of_node = dp;
355
356	intr = of_get_property(dp, "intr", &len);
357	if (intr) {
358		op->archdata.num_irqs = len / sizeof(struct linux_prom_irqs);
359		for (i = 0; i < op->archdata.num_irqs; i++)
360			op->archdata.irqs[i] =
361			    sparc_config.build_device_irq(op, intr[i].pri);
362	} else {
363		const unsigned int *irq =
364			of_get_property(dp, "interrupts", &len);
365
366		if (irq) {
367			op->archdata.num_irqs = len / sizeof(unsigned int);
368			for (i = 0; i < op->archdata.num_irqs; i++)
369				op->archdata.irqs[i] =
370				    sparc_config.build_device_irq(op, irq[i]);
371		} else {
372			op->archdata.num_irqs = 0;
373		}
374	}
375
376	build_device_resources(op, parent);
377
378	op->dev.parent = parent;
379	op->dev.bus = &platform_bus_type;
380	if (!parent)
381		dev_set_name(&op->dev, "root");
382	else
383		dev_set_name(&op->dev, "%08x", dp->phandle);
384
385	op->dev.coherent_dma_mask = DMA_BIT_MASK(32);
386	op->dev.dma_mask = &op->dev.coherent_dma_mask;
387
388	if (of_device_register(op)) {
389		printk("%pOF: Could not register of device.\n", dp);
 
390		kfree(op);
391		op = NULL;
392	}
393
394	return op;
395}
396
397static void __init scan_tree(struct device_node *dp, struct device *parent)
398{
399	while (dp) {
400		struct platform_device *op = scan_one_device(dp, parent);
401
402		if (op)
403			scan_tree(dp->child, &op->dev);
404
405		dp = dp->sibling;
406	}
407}
408
409static int __init scan_of_devices(void)
410{
411	struct device_node *root = of_find_node_by_path("/");
412	struct platform_device *parent;
413
414	parent = scan_one_device(root, NULL);
415	if (!parent)
416		return 0;
417
418	scan_tree(root->child, &parent->dev);
419	return 0;
420}
421postcore_initcall(scan_of_devices);
422
423static int __init of_debug(char *str)
424{
425	int val = 0;
426
427	get_option(&str, &val);
428	if (val & 1)
429		of_resource_verbose = 1;
430	return 1;
431}
432
433__setup("of_debug=", of_debug);