aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/platform/olpc/olpc_dt.c
blob: d6ee9298692006115edb0c8e7124e7e24d4f9edc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
/*
 * OLPC-specific OFW device tree support code.
 *
 * Paul Mackerras	August 1996.
 * Copyright (C) 1996-2005 Paul Mackerras.
 *
 *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
 *    {engebret|bergner}@us.ibm.com
 *
 *  Adapted for sparc by David S. Miller davem@davemloft.net
 *  Adapted for x86/OLPC by Andres Salomon <dilinger@queued.net>
 *
 *      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 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/bootmem.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/of_pdt.h>
#include <asm/olpc.h>
#include <asm/olpc_ofw.h>

static phandle __init olpc_dt_getsibling(phandle node)
{
	const void *args[] = { (void *)node };
	void *res[] = { &node };

	if ((s32)node == -1)
		return 0;

	if (olpc_ofw("peer", args, res) || (s32)node == -1)
		return 0;

	return node;
}

static phandle __init olpc_dt_getchild(phandle node)
{
	const void *args[] = { (void *)node };
	void *res[] = { &node };

	if ((s32)node == -1)
		return 0;

	if (olpc_ofw("child", args, res) || (s32)node == -1) {
		pr_err("PROM: %s: fetching child failed!\n", __func__);
		return 0;
	}

	return node;
}

static int __init olpc_dt_getproplen(phandle node, const char *prop)
{
	const void *args[] = { (void *)node, prop };
	int len;
	void *res[] = { &len };

	if ((s32)node == -1)
		return -1;

	if (olpc_ofw("getproplen", args, res)) {
		pr_err("PROM: %s: getproplen failed!\n", __func__);
		return -1;
	}

	return len;
}

static int __init olpc_dt_getproperty(phandle node, const char *prop,
		char *buf, int bufsize)
{
	int plen;

	plen = olpc_dt_getproplen(node, prop);
	if (plen > bufsize || plen < 1) {
		return -1;
	} else {
		const void *args[] = { (void *)node, prop, buf, (void *)plen };
		void *res[] = { &plen };

		if (olpc_ofw("getprop", args, res)) {
			pr_err("PROM: %s: getprop failed!\n", __func__);
			return -1;
		}
	}

	return plen;
}

static int __init olpc_dt_nextprop(phandle node, char *prev, char *buf)
{
	const void *args[] = { (void *)node, prev, buf };
	int success;
	void *res[] = { &success };

	buf[0] = '\0';

	if ((s32)node == -1)
		return -1;

	if (olpc_ofw("nextprop", args, res) || success != 1)
		return -1;

	return 0;
}

static int __init olpc_dt_pkg2path(phandle node, char *buf,
		const int buflen, int *len)
{
	const void *args[] = { (void *)node, buf, (void *)buflen };
	void *res[] = { len };

	if ((s32)node == -1)
		return -1;

	if (olpc_ofw("package-to-path", args, res) || *len < 1)
		return -1;

	return 0;
}

static unsigned int prom_early_allocated __initdata;

void * __init prom_early_alloc(unsigned long size)
{
	static u8 *mem;
	static size_t free_mem;
	void *res;

	if (free_mem < size) {
		const size_t chunk_size = max(PAGE_SIZE, size);

		/*
		 * To mimimize the number of allocations, grab at least
		 * PAGE_SIZE of memory (that's an arbitrary choice that's
		 * fast enough on the platforms we care about while minimizing
		 * wasted bootmem) and hand off chunks of it to callers.
		 */
		res = alloc_bootmem(chunk_size);
		BUG_ON(!res);
		prom_early_allocated += chunk_size;
		memset(res, 0, chunk_size);
		free_mem = chunk_size;
		mem = res;
	}

	/* allocate from the local cache */
	free_mem -= size;
	res = mem;
	mem += size;
	return res;
}

static struct of_pdt_ops prom_olpc_ops __initdata = {
	.nextprop = olpc_dt_nextprop,
	.getproplen = olpc_dt_getproplen,
	.getproperty = olpc_dt_getproperty,
	.getchild = olpc_dt_getchild,
	.getsibling = olpc_dt_getsibling,
	.pkg2path = olpc_dt_pkg2path,
};

static phandle __init olpc_dt_finddevice(const char *path)
{
	phandle node;
	const void *args[] = { path };
	void *res[] = { &node };

	if (olpc_ofw("finddevice", args, res)) {
		pr_err("olpc_dt: finddevice failed!\n");
		return 0;
	}

	if ((s32) node == -1)
		return 0;

	return node;
}

static int __init olpc_dt_interpret(const char *words)
{
	int result;
	const void *args[] = { words };
	void *res[] = { &result };

	if (olpc_ofw("interpret", args, res)) {
		pr_err("olpc_dt: interpret failed!\n");
		return -1;
	}

	return result;
}

/*
 * Extract board revision directly from OFW device tree.
 * We can't use olpc_platform_info because that hasn't been set up yet.
 */
static u32 __init olpc_dt_get_board_revision(void)
{
	phandle node;
	__be32 rev;
	int r;

	node = olpc_dt_finddevice("/");
	if (!node)
		return 0;

	r = olpc_dt_getproperty(node, "board-revision-int",
				(char *) &rev, sizeof(rev));
	if (r < 0)
		return 0;

	return be32_to_cpu(rev);
}

void __init olpc_dt_fixup(void)
{
	int r;
	char buf[64];
	phandle node;
	u32 board_rev;

	node = olpc_dt_finddevice("/battery@0");
	if (!node)
		return;

	/*
	 * If the battery node has a compatible property, we are running a new
	 * enough firmware and don't have fixups to make.
	 */
	r = olpc_dt_getproperty(node, "compatible", buf, sizeof(buf));
	if (r > 0)
		return;

	pr_info("PROM DT: Old firmware detected, applying fixes\n");

	/* Add olpc,xo1-battery compatible marker to battery node */
	olpc_dt_interpret("\" /battery@0\" find-device"
		" \" olpc,xo1-battery\" +compatible"
		" device-end");

	board_rev = olpc_dt_get_board_revision();
	if (!board_rev)
		return;

	if (board_rev >= olpc_board_pre(0xd0)) {
		/* XO-1.5: add dcon device */
		olpc_dt_interpret("\" /pci/display@1\" find-device"
			" new-device"
			" \" dcon\" device-name \" olpc,xo1-dcon\" +compatible"
			" finish-device device-end");
	} else {
		/* XO-1: add dcon device, mark RTC as olpc,xo1-rtc */
		olpc_dt_interpret("\" /pci/display@1,1\" find-device"
			" new-device"
			" \" dcon\" device-name \" olpc,xo1-dcon\" +compatible"
			" finish-device device-end"
			" \" /rtc\" find-device"
			" \" olpc,xo1-rtc\" +compatible"
			" device-end");
	}
}

void __init olpc_dt_build_devicetree(void)
{
	phandle root;

	if (!olpc_ofw_is_installed())
		return;

	olpc_dt_fixup();

	root = olpc_dt_getsibling(0);
	if (!root) {
		pr_err("PROM: unable to get root node from OFW!\n");
		return;
	}
	of_pdt_build_devicetree(root, &prom_olpc_ops);

	pr_info("PROM DT: Built device tree with %u bytes of memory.\n",
			prom_early_allocated);
}

/* A list of DT node/bus matches that we want to expose as platform devices */
static struct of_device_id __initdata of_ids[] = {
	{ .compatible = "olpc,xo1-battery" },
	{ .compatible = "olpc,xo1-dcon" },
	{ .compatible = "olpc,xo1-rtc" },
	{},
};

static int __init olpc_create_platform_devices(void)
{
	if (machine_is_olpc())
		return of_platform_bus_probe(NULL, of_ids, NULL);
	else
		return 0;
}
device_initcall(olpc_create_platform_devices);