[deliverable/linux.git] / drivers / of / fdt_address.c

/*
 * FDT Address translation based on u-boot fdt_support.c which in turn was
 * based on the kernel unflattened DT address translation code.
 *
 * (C) Copyright 2007
 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
 *
 * Copyright 2010-2011 Freescale Semiconductor, Inc.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 */
#include <linux/kernel.h>
#include <linux/libfdt.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/sizes.h>

/* Max address size we deal with */
#define OF_MAX_ADDR_CELLS	4
#define OF_CHECK_COUNTS(na, ns)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS && \
			(ns) > 0)

/* Debug utility */
#ifdef DEBUG
static void __init of_dump_addr(const char *s, const __be32 *addr, int na)
{
	pr_debug("%s", s);
	while(na--)
		pr_cont(" %08x", *(addr++));
	pr_debug("\n");
}
#else
static void __init of_dump_addr(const char *s, const __be32 *addr, int na) { }
#endif

/* Callbacks for bus specific translators */
struct of_bus {
	void		(*count_cells)(const void *blob, int parentoffset,
				int *addrc, int *sizec);
	u64		(*map)(__be32 *addr, const __be32 *range,
				int na, int ns, int pna);
	int		(*translate)(__be32 *addr, u64 offset, int na);
};

/* Default translator (generic bus) */
static void __init fdt_bus_default_count_cells(const void *blob, int parentoffset,
					       int *addrc, int *sizec)
{
	const __be32 *prop;

	if (addrc) {
		prop = fdt_getprop(blob, parentoffset, "#address-cells", NULL);
		if (prop)
			*addrc = be32_to_cpup(prop);
		else
			*addrc = dt_root_addr_cells;
	}

	if (sizec) {
		prop = fdt_getprop(blob, parentoffset, "#size-cells", NULL);
		if (prop)
			*sizec = be32_to_cpup(prop);
		else
			*sizec = dt_root_size_cells;
	}
}

static u64 __init fdt_bus_default_map(__be32 *addr, const __be32 *range,
				      int na, int ns, int pna)
{
	u64 cp, s, da;

	cp = of_read_number(range, na);
	s  = of_read_number(range + na + pna, ns);
	da = of_read_number(addr, na);

	pr_debug("FDT: default map, cp=%llx, s=%llx, da=%llx\n",
	    cp, s, da);

	if (da < cp || da >= (cp + s))
		return OF_BAD_ADDR;
	return da - cp;
}

static int __init fdt_bus_default_translate(__be32 *addr, u64 offset, int na)
{
	u64 a = of_read_number(addr, na);
	memset(addr, 0, na * 4);
	a += offset;
	if (na > 1)
		addr[na - 2] = cpu_to_fdt32(a >> 32);
	addr[na - 1] = cpu_to_fdt32(a & 0xffffffffu);

	return 0;
}

/* Array of bus specific translators */
static const struct of_bus of_busses[] __initconst = {
	/* Default */
	{
		.count_cells = fdt_bus_default_count_cells,
		.map = fdt_bus_default_map,
		.translate = fdt_bus_default_translate,
	},
};

static int __init fdt_translate_one(const void *blob, int parent,
				    const struct of_bus *bus,
				    const struct of_bus *pbus, __be32 *addr,
				    int na, int ns, int pna, const char *rprop)
{
	const __be32 *ranges;
	int rlen;
	int rone;
	u64 offset = OF_BAD_ADDR;

	ranges = fdt_getprop(blob, parent, rprop, &rlen);
	if (!ranges)
		return 1;
	if (rlen == 0) {
		offset = of_read_number(addr, na);
		memset(addr, 0, pna * 4);
		pr_debug("FDT: empty ranges, 1:1 translation\n");
		goto finish;
	}

	pr_debug("FDT: walking ranges...\n");

	/* Now walk through the ranges */
	rlen /= 4;
	rone = na + pna + ns;
	for (; rlen >= rone; rlen -= rone, ranges += rone) {
		offset = bus->map(addr, ranges, na, ns, pna);
		if (offset != OF_BAD_ADDR)
			break;
	}
	if (offset == OF_BAD_ADDR) {
		pr_debug("FDT: not found !\n");
		return 1;
	}
	memcpy(addr, ranges + na, 4 * pna);

 finish:
	of_dump_addr("FDT: parent translation for:", addr, pna);
	pr_debug("FDT: with offset: %llx\n", offset);

	/* Translate it into parent bus space */
	return pbus->translate(addr, offset, pna);
}

/*
 * Translate an address from the device-tree into a CPU physical address,
 * this walks up the tree and applies the various bus mappings on the
 * way.
 *
 * Note: We consider that crossing any level with #size-cells == 0 to mean
 * that translation is impossible (that is we are not dealing with a value
 * that can be mapped to a cpu physical address). This is not really specified
 * that way, but this is traditionally the way IBM at least do things
 */
u64 __init fdt_translate_address(const void *blob, int node_offset)
{
	int parent, len;
	const struct of_bus *bus, *pbus;
	const __be32 *reg;
	__be32 addr[OF_MAX_ADDR_CELLS];
	int na, ns, pna, pns;
	u64 result = OF_BAD_ADDR;

	pr_debug("FDT: ** translation for device %s **\n",
		 fdt_get_name(blob, node_offset, NULL));

	reg = fdt_getprop(blob, node_offset, "reg", &len);
	if (!reg) {
		pr_err("FDT: warning: device tree node '%s' has no address.\n",
			fdt_get_name(blob, node_offset, NULL));
		goto bail;
	}

	/* Get parent & match bus type */
	parent = fdt_parent_offset(blob, node_offset);
	if (parent < 0)
		goto bail;
	bus = &of_busses[0];

	/* Cound address cells & copy address locally */
	bus->count_cells(blob, parent, &na, &ns);
	if (!OF_CHECK_COUNTS(na, ns)) {
		pr_err("FDT: Bad cell count for %s\n",
		       fdt_get_name(blob, node_offset, NULL));
		goto bail;
	}
	memcpy(addr, reg, na * 4);

	pr_debug("FDT: bus (na=%d, ns=%d) on %s\n",
		 na, ns, fdt_get_name(blob, parent, NULL));
	of_dump_addr("OF: translating address:", addr, na);

	/* Translate */
	for (;;) {
		/* Switch to parent bus */
		node_offset = parent;
		parent = fdt_parent_offset(blob, node_offset);

		/* If root, we have finished */
		if (parent < 0) {
			pr_debug("FDT: reached root node\n");
			result = of_read_number(addr, na);
			break;
		}

		/* Get new parent bus and counts */
		pbus = &of_busses[0];
		pbus->count_cells(blob, parent, &pna, &pns);
		if (!OF_CHECK_COUNTS(pna, pns)) {
			pr_err("FDT: Bad cell count for %s\n",
				fdt_get_name(blob, node_offset, NULL));
			break;
		}

		pr_debug("FDT: parent bus (na=%d, ns=%d) on %s\n",
			 pna, pns, fdt_get_name(blob, parent, NULL));

		/* Apply bus translation */
		if (fdt_translate_one(blob, node_offset, bus, pbus,
					addr, na, ns, pna, "ranges"))
			break;

		/* Complete the move up one level */
		na = pna;
		ns = pns;
		bus = pbus;

		of_dump_addr("FDT: one level translation:", addr, na);
	}
 bail:
	return result;
}
Commit	Line	Data
e06e8b27 RH	1	/*
	2	* FDT Address translation based on u-boot fdt_support.c which in turn was
	3	* based on the kernel unflattened DT address translation code.
	4	*
	5	* (C) Copyright 2007
	6	* Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com
	7	*
	8	* Copyright 2010-2011 Freescale Semiconductor, Inc.
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License as published by
	12	* the Free Software Foundation; either version 2, or (at your option)
	13	* any later version.
	14	*/
	15	#include <linux/kernel.h>
	16	#include <linux/libfdt.h>
	17	#include <linux/of.h>
	18	#include <linux/of_fdt.h>
	19	#include <linux/sizes.h>
	20
	21	/* Max address size we deal with */
	22	#define OF_MAX_ADDR_CELLS 4
	23	#define OF_CHECK_COUNTS(na, ns) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS && \
	24	(ns) > 0)
	25
	26	/* Debug utility */
	27	#ifdef DEBUG
	28	static void __init of_dump_addr(const char s, const __be32 addr, int na)
	29	{
	30	pr_debug("%s", s);
	31	while(na--)
	32	pr_cont(" %08x", *(addr++));
	33	pr_debug("\n");
	34	}
	35	#else
	36	static void __init of_dump_addr(const char s, const __be32 addr, int na) { }
	37	#endif
	38
	39	/* Callbacks for bus specific translators */
	40	struct of_bus {
	41	void (count_cells)(const void blob, int parentoffset,
	42	int addrc, int sizec);
	43	u64 (map)(__be32 addr, const __be32 *range,
	44	int na, int ns, int pna);
	45	int (translate)(__be32 addr, u64 offset, int na);
	46	};
	47
	48	/* Default translator (generic bus) */
	49	static void __init fdt_bus_default_count_cells(const void *blob, int parentoffset,
	50	int addrc, int sizec)
	51	{
	52	const __be32 *prop;
	53
	54	if (addrc) {
	55	prop = fdt_getprop(blob, parentoffset, "#address-cells", NULL);
	56	if (prop)
	57	*addrc = be32_to_cpup(prop);
	58	else
	59	*addrc = dt_root_addr_cells;
	60	}
	61
	62	if (sizec) {
	63	prop = fdt_getprop(blob, parentoffset, "#size-cells", NULL);
	64	if (prop)
65	*sizec = be32_to_cpup(prop);
66	else
67	*sizec = dt_root_size_cells;
68	}
69	}
70
71	static u64 __init fdt_bus_default_map(__be32 addr, const __be32 range,
72	int na, int ns, int pna)
73	{
74	u64 cp, s, da;
75
76	cp = of_read_number(range, na);
77	s = of_read_number(range + na + pna, ns);
78	da = of_read_number(addr, na);
79
80	pr_debug("FDT: default map, cp=%llx, s=%llx, da=%llx\n",
81	cp, s, da);
82
83	if (da < cp \|\| da >= (cp + s))
84	return OF_BAD_ADDR;
85	return da - cp;
86	}
87
88	static int __init fdt_bus_default_translate(__be32 *addr, u64 offset, int na)
89	{
90	u64 a = of_read_number(addr, na);
91	memset(addr, 0, na * 4);
92	a += offset;
93	if (na > 1)
94	addr[na - 2] = cpu_to_fdt32(a >> 32);
95	addr[na - 1] = cpu_to_fdt32(a & 0xffffffffu);
96
97	return 0;
98	}
99
100	/* Array of bus specific translators */
101	static const struct of_bus of_busses[] __initconst = {
102	/* Default */
103	{
104	.count_cells = fdt_bus_default_count_cells,
105	.map = fdt_bus_default_map,
106	.translate = fdt_bus_default_translate,
107	},
108	};
109
110	static int __init fdt_translate_one(const void *blob, int parent,
111	const struct of_bus *bus,
112	const struct of_bus pbus, __be32 addr,
113	int na, int ns, int pna, const char *rprop)
114	{
115	const __be32 *ranges;
116	int rlen;
117	int rone;
118	u64 offset = OF_BAD_ADDR;
119
120	ranges = fdt_getprop(blob, parent, rprop, &rlen);
121	if (!ranges)
122	return 1;
123	if (rlen == 0) {
124	offset = of_read_number(addr, na);
125	memset(addr, 0, pna * 4);
126	pr_debug("FDT: empty ranges, 1:1 translation\n");
127	goto finish;
128	}
129
130	pr_debug("FDT: walking ranges...\n");
131
132	/* Now walk through the ranges */
133	rlen /= 4;
134	rone = na + pna + ns;
135	for (; rlen >= rone; rlen -= rone, ranges += rone) {
136	offset = bus->map(addr, ranges, na, ns, pna);
137	if (offset != OF_BAD_ADDR)
138	break;
139	}
140	if (offset == OF_BAD_ADDR) {
141	pr_debug("FDT: not found !\n");
142	return 1;
143	}
144	memcpy(addr, ranges + na, 4 * pna);
145
146	finish:
147	of_dump_addr("FDT: parent translation for:", addr, pna);
148	pr_debug("FDT: with offset: %llx\n", offset);
149
150	/* Translate it into parent bus space */
151	return pbus->translate(addr, offset, pna);
152	}
153
154	/*
155	* Translate an address from the device-tree into a CPU physical address,
156	* this walks up the tree and applies the various bus mappings on the
157	* way.
158	*
159	* Note: We consider that crossing any level with #size-cells == 0 to mean
160	* that translation is impossible (that is we are not dealing with a value
161	* that can be mapped to a cpu physical address). This is not really specified
162	* that way, but this is traditionally the way IBM at least do things
163	*/
164	u64 __init fdt_translate_address(const void *blob, int node_offset)
165	{
166	int parent, len;
167	const struct of_bus bus, pbus;
168	const __be32 *reg;
169	__be32 addr[OF_MAX_ADDR_CELLS];
170	int na, ns, pna, pns;
171	u64 result = OF_BAD_ADDR;
172
173	pr_debug("FDT: translation for device %s \n",
174	fdt_get_name(blob, node_offset, NULL));
175
176	reg = fdt_getprop(blob, node_offset, "reg", &len);
177	if (!reg) {
178	pr_err("FDT: warning: device tree node '%s' has no address.\n",
179	fdt_get_name(blob, node_offset, NULL));
180	goto bail;
181	}
182
183	/* Get parent & match bus type */
184	parent = fdt_parent_offset(blob, node_offset);
185	if (parent < 0)
186	goto bail;
187	bus = &of_busses[0];
188
189	/* Cound address cells & copy address locally */
190	bus->count_cells(blob, parent, &na, &ns);
191	if (!OF_CHECK_COUNTS(na, ns)) {
192	pr_err("FDT: Bad cell count for %s\n",
193	fdt_get_name(blob, node_offset, NULL));
194	goto bail;
195	}
196	memcpy(addr, reg, na * 4);
197
198	pr_debug("FDT: bus (na=%d, ns=%d) on %s\n",
199	na, ns, fdt_get_name(blob, parent, NULL));
200	of_dump_addr("OF: translating address:", addr, na);
201
202	/* Translate */
203	for (;;) {
204	/* Switch to parent bus */
205	node_offset = parent;
206	parent = fdt_parent_offset(blob, node_offset);
207
208	/* If root, we have finished */
209	if (parent < 0) {
210	pr_debug("FDT: reached root node\n");
211	result = of_read_number(addr, na);
212	break;
213	}
214
215	/* Get new parent bus and counts */
216	pbus = &of_busses[0];
217	pbus->count_cells(blob, parent, &pna, &pns);
218	if (!OF_CHECK_COUNTS(pna, pns)) {
219	pr_err("FDT: Bad cell count for %s\n",
220	fdt_get_name(blob, node_offset, NULL));
221	break;
222	}
223
224	pr_debug("FDT: parent bus (na=%d, ns=%d) on %s\n",
225	pna, pns, fdt_get_name(blob, parent, NULL));
226
227	/* Apply bus translation */
228	if (fdt_translate_one(blob, node_offset, bus, pbus,
229	addr, na, ns, pna, "ranges"))
230	break;
231
232	/* Complete the move up one level */
233	na = pna;
234	ns = pns;
235	bus = pbus;
236
237	of_dump_addr("FDT: one level translation:", addr, na);
238	}
239	bail:
240	return result;
241	}