aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/platform/olpc/olpc.c
blob: a4bee53c2e549a5ff28f6ccd8a85c3abce696ec4 (plain) (blame)
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
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
/*
 * Support for the OLPC DCON and OLPC EC access
 *
 * Copyright © 2006  Advanced Micro Devices, Inc.
 * Copyright © 2007-2008  Andres Salomon <dilinger@debian.org>
 *
 * 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/init.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/string.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/syscore_ops.h>
#include <linux/debugfs.h>
#include <linux/mutex.h>

#include <asm/geode.h>
#include <asm/setup.h>
#include <asm/olpc.h>
#include <asm/olpc_ofw.h>

struct olpc_platform_t olpc_platform_info;
EXPORT_SYMBOL_GPL(olpc_platform_info);

static DEFINE_SPINLOCK(ec_lock);

/* debugfs interface to EC commands */
#define EC_MAX_CMD_ARGS (5 + 1)	/* cmd byte + 5 args */
#define EC_MAX_CMD_REPLY (8)

static struct dentry *ec_debugfs_dir;
static DEFINE_MUTEX(ec_debugfs_cmd_lock);
static unsigned char ec_debugfs_resp[EC_MAX_CMD_REPLY];
static unsigned int ec_debugfs_resp_bytes;

/* EC event mask to be applied during suspend (defining wakeup sources). */
static u16 ec_wakeup_mask;

/* what the timeout *should* be (in ms) */
#define EC_BASE_TIMEOUT 20

/* the timeout that bugs in the EC might force us to actually use */
static int ec_timeout = EC_BASE_TIMEOUT;

static int __init olpc_ec_timeout_set(char *str)
{
	if (get_option(&str, &ec_timeout) != 1) {
		ec_timeout = EC_BASE_TIMEOUT;
		printk(KERN_ERR "olpc-ec:  invalid argument to "
				"'olpc_ec_timeout=', ignoring!\n");
	}
	printk(KERN_DEBUG "olpc-ec:  using %d ms delay for EC commands.\n",
			ec_timeout);
	return 1;
}
__setup("olpc_ec_timeout=", olpc_ec_timeout_set);

/*
 * These {i,o}bf_status functions return whether the buffers are full or not.
 */

static inline unsigned int ibf_status(unsigned int port)
{
	return !!(inb(port) & 0x02);
}

static inline unsigned int obf_status(unsigned int port)
{
	return inb(port) & 0x01;
}

#define wait_on_ibf(p, d) __wait_on_ibf(__LINE__, (p), (d))
static int __wait_on_ibf(unsigned int line, unsigned int port, int desired)
{
	unsigned int timeo;
	int state = ibf_status(port);

	for (timeo = ec_timeout; state != desired && timeo; timeo--) {
		mdelay(1);
		state = ibf_status(port);
	}

	if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) &&
			timeo < (ec_timeout - EC_BASE_TIMEOUT)) {
		printk(KERN_WARNING "olpc-ec:  %d: waited %u ms for IBF!\n",
				line, ec_timeout - timeo);
	}

	return !(state == desired);
}

#define wait_on_obf(p, d) __wait_on_obf(__LINE__, (p), (d))
static int __wait_on_obf(unsigned int line, unsigned int port, int desired)
{
	unsigned int timeo;
	int state = obf_status(port);

	for (timeo = ec_timeout; state != desired && timeo; timeo--) {
		mdelay(1);
		state = obf_status(port);
	}

	if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) &&
			timeo < (ec_timeout - EC_BASE_TIMEOUT)) {
		printk(KERN_WARNING "olpc-ec:  %d: waited %u ms for OBF!\n",
				line, ec_timeout - timeo);
	}

	return !(state == desired);
}

/*
 * This allows the kernel to run Embedded Controller commands.  The EC is
 * documented at <http://wiki.laptop.org/go/Embedded_controller>, and the
 * available EC commands are here:
 * <http://wiki.laptop.org/go/Ec_specification>.  Unfortunately, while
 * OpenFirmware's source is available, the EC's is not.
 */
int olpc_ec_cmd(unsigned char cmd, unsigned char *inbuf, size_t inlen,
		unsigned char *outbuf,  size_t outlen)
{
	unsigned long flags;
	int ret = -EIO;
	int i;
	int restarts = 0;

	spin_lock_irqsave(&ec_lock, flags);

	/* Clear OBF */
	for (i = 0; i < 10 && (obf_status(0x6c) == 1); i++)
		inb(0x68);
	if (i == 10) {
		printk(KERN_ERR "olpc-ec:  timeout while attempting to "
				"clear OBF flag!\n");
		goto err;
	}

	if (wait_on_ibf(0x6c, 0)) {
		printk(KERN_ERR "olpc-ec:  timeout waiting for EC to "
				"quiesce!\n");
		goto err;
	}

restart:
	/*
	 * Note that if we time out during any IBF checks, that's a failure;
	 * we have to return.  There's no way for the kernel to clear that.
	 *
	 * If we time out during an OBF check, we can restart the command;
	 * reissuing it will clear the OBF flag, and we should be alright.
	 * The OBF flag will sometimes misbehave due to what we believe
	 * is a hardware quirk..
	 */
	pr_devel("olpc-ec:  running cmd 0x%x\n", cmd);
	outb(cmd, 0x6c);

	if (wait_on_ibf(0x6c, 0)) {
		printk(KERN_ERR "olpc-ec:  timeout waiting for EC to read "
				"command!\n");
		goto err;
	}

	if (inbuf && inlen) {
		/* write data to EC */
		for (i = 0; i < inlen; i++) {
			pr_devel("olpc-ec:  sending cmd arg 0x%x\n", inbuf[i]);
			outb(inbuf[i], 0x68);
			if (wait_on_ibf(0x6c, 0)) {
				printk(KERN_ERR "olpc-ec:  timeout waiting for"
						" EC accept data!\n");
				goto err;
			}
		}
	}
	if (outbuf && outlen) {
		/* read data from EC */
		for (i = 0; i < outlen; i++) {
			if (wait_on_obf(0x6c, 1)) {
				printk(KERN_ERR "olpc-ec:  timeout waiting for"
						" EC to provide data!\n");
				if (restarts++ < 10)
					goto restart;
				goto err;
			}
			outbuf[i] = inb(0x68);
			pr_devel("olpc-ec:  received 0x%x\n", outbuf[i]);
		}
	}

	ret = 0;
err:
	spin_unlock_irqrestore(&ec_lock, flags);
	return ret;
}
EXPORT_SYMBOL_GPL(olpc_ec_cmd);

void olpc_ec_wakeup_set(u16 value)
{
	ec_wakeup_mask |= value;
}
EXPORT_SYMBOL_GPL(olpc_ec_wakeup_set);

void olpc_ec_wakeup_clear(u16 value)
{
	ec_wakeup_mask &= ~value;
}
EXPORT_SYMBOL_GPL(olpc_ec_wakeup_clear);

/*
 * Returns true if the compile and runtime configurations allow for EC events
 * to wake the system.
 */
bool olpc_ec_wakeup_available(void)
{
	if (!machine_is_olpc())
		return false;

	/*
	 * XO-1 EC wakeups are available when olpc-xo1-sci driver is
	 * compiled in
	 */
#ifdef CONFIG_OLPC_XO1_SCI
	if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) /* XO-1 */
		return true;
#endif

	/*
	 * XO-1.5 EC wakeups are available when olpc-xo15-sci driver is
	 * compiled in
	 */
#ifdef CONFIG_OLPC_XO15_SCI
	if (olpc_platform_info.boardrev >= olpc_board_pre(0xd0)) /* XO-1.5 */
		return true;
#endif

	return false;
}
EXPORT_SYMBOL_GPL(olpc_ec_wakeup_available);

int olpc_ec_mask_write(u16 bits)
{
	if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
		__be16 ec_word = cpu_to_be16(bits);
		return olpc_ec_cmd(EC_WRITE_EXT_SCI_MASK, (void *) &ec_word, 2,
				   NULL, 0);
	} else {
		unsigned char ec_byte = bits & 0xff;
		return olpc_ec_cmd(EC_WRITE_SCI_MASK, &ec_byte, 1, NULL, 0);
	}
}
EXPORT_SYMBOL_GPL(olpc_ec_mask_write);

int olpc_ec_sci_query(u16 *sci_value)
{
	int ret;

	if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
		__be16 ec_word;
		ret = olpc_ec_cmd(EC_EXT_SCI_QUERY,
			NULL, 0, (void *) &ec_word, 2);
		if (ret == 0)
			*sci_value = be16_to_cpu(ec_word);
	} else {
		unsigned char ec_byte;
		ret = olpc_ec_cmd(EC_SCI_QUERY, NULL, 0, &ec_byte, 1);
		if (ret == 0)
			*sci_value = ec_byte;
	}

	return ret;
}
EXPORT_SYMBOL_GPL(olpc_ec_sci_query);

static ssize_t ec_debugfs_cmd_write(struct file *file, const char __user *buf,
				    size_t size, loff_t *ppos)
{
	int i, m;
	unsigned char ec_cmd[EC_MAX_CMD_ARGS];
	unsigned int ec_cmd_int[EC_MAX_CMD_ARGS];
	char cmdbuf[64];
	int ec_cmd_bytes;

	mutex_lock(&ec_debugfs_cmd_lock);

	size = simple_write_to_buffer(cmdbuf, sizeof(cmdbuf), ppos, buf, size);

	m = sscanf(cmdbuf, "%x:%u %x %x %x %x %x", &ec_cmd_int[0],
		   &ec_debugfs_resp_bytes,
		   &ec_cmd_int[1], &ec_cmd_int[2], &ec_cmd_int[3],
		   &ec_cmd_int[4], &ec_cmd_int[5]);
	if (m < 2 || ec_debugfs_resp_bytes > EC_MAX_CMD_REPLY) {
		/* reset to prevent overflow on read */
		ec_debugfs_resp_bytes = 0;

		printk(KERN_DEBUG "olpc-ec: bad ec cmd:  "
		       "cmd:response-count [arg1 [arg2 ...]]\n");
		size = -EINVAL;
		goto out;
	}

	/* convert scanf'd ints to char */
	ec_cmd_bytes = m - 2;
	for (i = 0; i <= ec_cmd_bytes; i++)
		ec_cmd[i] = ec_cmd_int[i];

	printk(KERN_DEBUG "olpc-ec: debugfs cmd 0x%02x with %d args "
	       "%02x %02x %02x %02x %02x, want %d returns\n",
	       ec_cmd[0], ec_cmd_bytes, ec_cmd[1], ec_cmd[2], ec_cmd[3],
	       ec_cmd[4], ec_cmd[5], ec_debugfs_resp_bytes);

	olpc_ec_cmd(ec_cmd[0], (ec_cmd_bytes == 0) ? NULL : &ec_cmd[1],
		    ec_cmd_bytes, ec_debugfs_resp, ec_debugfs_resp_bytes);

	printk(KERN_DEBUG "olpc-ec: response "
	       "%02x %02x %02x %02x %02x %02x %02x %02x (%d bytes expected)\n",
	       ec_debugfs_resp[0], ec_debugfs_resp[1], ec_debugfs_resp[2],
	       ec_debugfs_resp[3], ec_debugfs_resp[4], ec_debugfs_resp[5],
	       ec_debugfs_resp[6], ec_debugfs_resp[7], ec_debugfs_resp_bytes);

out:
	mutex_unlock(&ec_debugfs_cmd_lock);
	return size;
}

static ssize_t ec_debugfs_cmd_read(struct file *file, char __user *buf,
				   size_t size, loff_t *ppos)
{
	unsigned int i, r;
	char *rp;
	char respbuf[64];

	mutex_lock(&ec_debugfs_cmd_lock);
	rp = respbuf;
	rp += sprintf(rp, "%02x", ec_debugfs_resp[0]);
	for (i = 1; i < ec_debugfs_resp_bytes; i++)
		rp += sprintf(rp, ", %02x", ec_debugfs_resp[i]);
	mutex_unlock(&ec_debugfs_cmd_lock);
	rp += sprintf(rp, "\n");

	r = rp - respbuf;
	return simple_read_from_buffer(buf, size, ppos, respbuf, r);
}

static const struct file_operations ec_debugfs_genops = {
	.write	 = ec_debugfs_cmd_write,
	.read	 = ec_debugfs_cmd_read,
};

static void setup_debugfs(void)
{
	ec_debugfs_dir = debugfs_create_dir("olpc-ec", 0);
	if (ec_debugfs_dir == ERR_PTR(-ENODEV))
		return;

	debugfs_create_file("cmd", 0600, ec_debugfs_dir, NULL,
			    &ec_debugfs_genops);
}

static int olpc_ec_suspend(void)
{
	return olpc_ec_mask_write(ec_wakeup_mask);
}

static bool __init check_ofw_architecture(struct device_node *root)
{
	const char *olpc_arch;
	int propsize;

	olpc_arch = of_get_property(root, "architecture", &propsize);
	return propsize == 5 && strncmp("OLPC", olpc_arch, 5) == 0;
}

static u32 __init get_board_revision(struct device_node *root)
{
	int propsize;
	const __be32 *rev;

	rev = of_get_property(root, "board-revision-int", &propsize);
	if (propsize != 4)
		return 0;

	return be32_to_cpu(*rev);
}

static bool __init platform_detect(void)
{
	struct device_node *root = of_find_node_by_path("/");
	bool success;

	if (!root)
		return false;

	success = check_ofw_architecture(root);
	if (success) {
		olpc_platform_info.boardrev = get_board_revision(root);
		olpc_platform_info.flags |= OLPC_F_PRESENT;
	}

	of_node_put(root);
	return success;
}

static int __init add_xo1_platform_devices(void)
{
	struct platform_device *pdev;

	pdev = platform_device_register_simple("xo1-rfkill", -1, NULL, 0);
	if (IS_ERR(pdev))
		return PTR_ERR(pdev);

	pdev = platform_device_register_simple("olpc-xo1", -1, NULL, 0);
	if (IS_ERR(pdev))
		return PTR_ERR(pdev);

	return 0;
}

static struct syscore_ops olpc_syscore_ops = {
	.suspend = olpc_ec_suspend,
};

static int __init olpc_init(void)
{
	int r = 0;

	if (!olpc_ofw_present() || !platform_detect())
		return 0;

	spin_lock_init(&ec_lock);

	/* assume B1 and above models always have a DCON */
	if (olpc_board_at_least(olpc_board(0xb1)))
		olpc_platform_info.flags |= OLPC_F_DCON;

	/* get the EC revision */
	olpc_ec_cmd(EC_FIRMWARE_REV, NULL, 0,
			(unsigned char *) &olpc_platform_info.ecver, 1);

#ifdef CONFIG_PCI_OLPC
	/* If the VSA exists let it emulate PCI, if not emulate in kernel.
	 * XO-1 only. */
	if (olpc_platform_info.boardrev < olpc_board_pre(0xd0) &&
			!cs5535_has_vsa2())
		x86_init.pci.arch_init = pci_olpc_init;
#endif
	/* EC version 0x5f adds support for wide SCI mask */
	if (olpc_platform_info.ecver >= 0x5f)
		olpc_platform_info.flags |= OLPC_F_EC_WIDE_SCI;

	printk(KERN_INFO "OLPC board revision %s%X (EC=%x)\n",
			((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "",
			olpc_platform_info.boardrev >> 4,
			olpc_platform_info.ecver);

	if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) { /* XO-1 */
		r = add_xo1_platform_devices();
		if (r)
			return r;
	}

	register_syscore_ops(&olpc_syscore_ops);
	setup_debugfs();

	return 0;
}

postcore_initcall(olpc_init);