xref: /openbmc/linux/drivers/i2c/busses/i2c-piix4.c (revision bc05aa6e)
1 /*
2     Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl> and
3     Philip Edelbrock <phil@netroedge.com>
4 
5     This program is free software; you can redistribute it and/or modify
6     it under the terms of the GNU General Public License as published by
7     the Free Software Foundation; either version 2 of the License, or
8     (at your option) any later version.
9 
10     This program is distributed in the hope that it will be useful,
11     but WITHOUT ANY WARRANTY; without even the implied warranty of
12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13     GNU General Public License for more details.
14 */
15 
16 /*
17    Supports:
18 	Intel PIIX4, 440MX
19 	Serverworks OSB4, CSB5, CSB6, HT-1000, HT-1100
20 	ATI IXP200, IXP300, IXP400, SB600, SB700/SP5100, SB800
21 	AMD Hudson-2, ML, CZ
22 	SMSC Victory66
23 
24    Note: we assume there can only be one device, with one or more
25    SMBus interfaces.
26    The device can register multiple i2c_adapters (up to PIIX4_MAX_ADAPTERS).
27    For devices supporting multiple ports the i2c_adapter should provide
28    an i2c_algorithm to access them.
29 */
30 
31 #include <linux/module.h>
32 #include <linux/moduleparam.h>
33 #include <linux/pci.h>
34 #include <linux/kernel.h>
35 #include <linux/delay.h>
36 #include <linux/stddef.h>
37 #include <linux/ioport.h>
38 #include <linux/i2c.h>
39 #include <linux/slab.h>
40 #include <linux/dmi.h>
41 #include <linux/acpi.h>
42 #include <linux/io.h>
43 #include <linux/mutex.h>
44 
45 
46 /* PIIX4 SMBus address offsets */
47 #define SMBHSTSTS	(0 + piix4_smba)
48 #define SMBHSLVSTS	(1 + piix4_smba)
49 #define SMBHSTCNT	(2 + piix4_smba)
50 #define SMBHSTCMD	(3 + piix4_smba)
51 #define SMBHSTADD	(4 + piix4_smba)
52 #define SMBHSTDAT0	(5 + piix4_smba)
53 #define SMBHSTDAT1	(6 + piix4_smba)
54 #define SMBBLKDAT	(7 + piix4_smba)
55 #define SMBSLVCNT	(8 + piix4_smba)
56 #define SMBSHDWCMD	(9 + piix4_smba)
57 #define SMBSLVEVT	(0xA + piix4_smba)
58 #define SMBSLVDAT	(0xC + piix4_smba)
59 
60 /* count for request_region */
61 #define SMBIOSIZE	9
62 
63 /* PCI Address Constants */
64 #define SMBBA		0x090
65 #define SMBHSTCFG	0x0D2
66 #define SMBSLVC		0x0D3
67 #define SMBSHDW1	0x0D4
68 #define SMBSHDW2	0x0D5
69 #define SMBREV		0x0D6
70 
71 /* Other settings */
72 #define MAX_TIMEOUT	500
73 #define  ENABLE_INT9	0
74 
75 /* PIIX4 constants */
76 #define PIIX4_QUICK		0x00
77 #define PIIX4_BYTE		0x04
78 #define PIIX4_BYTE_DATA		0x08
79 #define PIIX4_WORD_DATA		0x0C
80 #define PIIX4_BLOCK_DATA	0x14
81 
82 /* Multi-port constants */
83 #define PIIX4_MAX_ADAPTERS 4
84 
85 /* SB800 constants */
86 #define SB800_PIIX4_SMB_IDX		0xcd6
87 
88 #define KERNCZ_IMC_IDX			0x3e
89 #define KERNCZ_IMC_DATA			0x3f
90 
91 /*
92  * SB800 port is selected by bits 2:1 of the smb_en register (0x2c)
93  * or the smb_sel register (0x2e), depending on bit 0 of register 0x2f.
94  * Hudson-2/Bolton port is always selected by bits 2:1 of register 0x2f.
95  */
96 #define SB800_PIIX4_PORT_IDX		0x2c
97 #define SB800_PIIX4_PORT_IDX_ALT	0x2e
98 #define SB800_PIIX4_PORT_IDX_SEL	0x2f
99 #define SB800_PIIX4_PORT_IDX_MASK	0x06
100 #define SB800_PIIX4_PORT_IDX_SHIFT	1
101 
102 /* On kerncz, SmBus0Sel is at bit 20:19 of PMx00 DecodeEn */
103 #define SB800_PIIX4_PORT_IDX_KERNCZ		0x02
104 #define SB800_PIIX4_PORT_IDX_MASK_KERNCZ	0x18
105 #define SB800_PIIX4_PORT_IDX_SHIFT_KERNCZ	3
106 
107 /* insmod parameters */
108 
109 /* If force is set to anything different from 0, we forcibly enable the
110    PIIX4. DANGEROUS! */
111 static int force;
112 module_param (force, int, 0);
113 MODULE_PARM_DESC(force, "Forcibly enable the PIIX4. DANGEROUS!");
114 
115 /* If force_addr is set to anything different from 0, we forcibly enable
116    the PIIX4 at the given address. VERY DANGEROUS! */
117 static int force_addr;
118 module_param_hw(force_addr, int, ioport, 0);
119 MODULE_PARM_DESC(force_addr,
120 		 "Forcibly enable the PIIX4 at the given address. "
121 		 "EXTREMELY DANGEROUS!");
122 
123 static int srvrworks_csb5_delay;
124 static struct pci_driver piix4_driver;
125 
126 static const struct dmi_system_id piix4_dmi_blacklist[] = {
127 	{
128 		.ident = "Sapphire AM2RD790",
129 		.matches = {
130 			DMI_MATCH(DMI_BOARD_VENDOR, "SAPPHIRE Inc."),
131 			DMI_MATCH(DMI_BOARD_NAME, "PC-AM2RD790"),
132 		},
133 	},
134 	{
135 		.ident = "DFI Lanparty UT 790FX",
136 		.matches = {
137 			DMI_MATCH(DMI_BOARD_VENDOR, "DFI Inc."),
138 			DMI_MATCH(DMI_BOARD_NAME, "LP UT 790FX"),
139 		},
140 	},
141 	{ }
142 };
143 
144 /* The IBM entry is in a separate table because we only check it
145    on Intel-based systems */
146 static const struct dmi_system_id piix4_dmi_ibm[] = {
147 	{
148 		.ident = "IBM",
149 		.matches = { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
150 	},
151 	{ },
152 };
153 
154 /*
155  * SB800 globals
156  * piix4_mutex_sb800 protects piix4_port_sel_sb800 and the pair
157  * of I/O ports at SB800_PIIX4_SMB_IDX.
158  */
159 static DEFINE_MUTEX(piix4_mutex_sb800);
160 static u8 piix4_port_sel_sb800;
161 static u8 piix4_port_mask_sb800;
162 static u8 piix4_port_shift_sb800;
163 static const char *piix4_main_port_names_sb800[PIIX4_MAX_ADAPTERS] = {
164 	" port 0", " port 2", " port 3", " port 4"
165 };
166 static const char *piix4_aux_port_name_sb800 = " port 1";
167 
168 struct i2c_piix4_adapdata {
169 	unsigned short smba;
170 
171 	/* SB800 */
172 	bool sb800_main;
173 	bool notify_imc;
174 	u8 port;		/* Port number, shifted */
175 };
176 
177 static int piix4_setup(struct pci_dev *PIIX4_dev,
178 		       const struct pci_device_id *id)
179 {
180 	unsigned char temp;
181 	unsigned short piix4_smba;
182 
183 	if ((PIIX4_dev->vendor == PCI_VENDOR_ID_SERVERWORKS) &&
184 	    (PIIX4_dev->device == PCI_DEVICE_ID_SERVERWORKS_CSB5))
185 		srvrworks_csb5_delay = 1;
186 
187 	/* On some motherboards, it was reported that accessing the SMBus
188 	   caused severe hardware problems */
189 	if (dmi_check_system(piix4_dmi_blacklist)) {
190 		dev_err(&PIIX4_dev->dev,
191 			"Accessing the SMBus on this system is unsafe!\n");
192 		return -EPERM;
193 	}
194 
195 	/* Don't access SMBus on IBM systems which get corrupted eeproms */
196 	if (dmi_check_system(piix4_dmi_ibm) &&
197 			PIIX4_dev->vendor == PCI_VENDOR_ID_INTEL) {
198 		dev_err(&PIIX4_dev->dev, "IBM system detected; this module "
199 			"may corrupt your serial eeprom! Refusing to load "
200 			"module!\n");
201 		return -EPERM;
202 	}
203 
204 	/* Determine the address of the SMBus areas */
205 	if (force_addr) {
206 		piix4_smba = force_addr & 0xfff0;
207 		force = 0;
208 	} else {
209 		pci_read_config_word(PIIX4_dev, SMBBA, &piix4_smba);
210 		piix4_smba &= 0xfff0;
211 		if(piix4_smba == 0) {
212 			dev_err(&PIIX4_dev->dev, "SMBus base address "
213 				"uninitialized - upgrade BIOS or use "
214 				"force_addr=0xaddr\n");
215 			return -ENODEV;
216 		}
217 	}
218 
219 	if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
220 		return -ENODEV;
221 
222 	if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
223 		dev_err(&PIIX4_dev->dev, "SMBus region 0x%x already in use!\n",
224 			piix4_smba);
225 		return -EBUSY;
226 	}
227 
228 	pci_read_config_byte(PIIX4_dev, SMBHSTCFG, &temp);
229 
230 	/* If force_addr is set, we program the new address here. Just to make
231 	   sure, we disable the PIIX4 first. */
232 	if (force_addr) {
233 		pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp & 0xfe);
234 		pci_write_config_word(PIIX4_dev, SMBBA, piix4_smba);
235 		pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp | 0x01);
236 		dev_info(&PIIX4_dev->dev, "WARNING: SMBus interface set to "
237 			"new address %04x!\n", piix4_smba);
238 	} else if ((temp & 1) == 0) {
239 		if (force) {
240 			/* This should never need to be done, but has been
241 			 * noted that many Dell machines have the SMBus
242 			 * interface on the PIIX4 disabled!? NOTE: This assumes
243 			 * I/O space and other allocations WERE done by the
244 			 * Bios!  Don't complain if your hardware does weird
245 			 * things after enabling this. :') Check for Bios
246 			 * updates before resorting to this.
247 			 */
248 			pci_write_config_byte(PIIX4_dev, SMBHSTCFG,
249 					      temp | 1);
250 			dev_notice(&PIIX4_dev->dev,
251 				   "WARNING: SMBus interface has been FORCEFULLY ENABLED!\n");
252 		} else {
253 			dev_err(&PIIX4_dev->dev,
254 				"SMBus Host Controller not enabled!\n");
255 			release_region(piix4_smba, SMBIOSIZE);
256 			return -ENODEV;
257 		}
258 	}
259 
260 	if (((temp & 0x0E) == 8) || ((temp & 0x0E) == 2))
261 		dev_dbg(&PIIX4_dev->dev, "Using IRQ for SMBus\n");
262 	else if ((temp & 0x0E) == 0)
263 		dev_dbg(&PIIX4_dev->dev, "Using SMI# for SMBus\n");
264 	else
265 		dev_err(&PIIX4_dev->dev, "Illegal Interrupt configuration "
266 			"(or code out of date)!\n");
267 
268 	pci_read_config_byte(PIIX4_dev, SMBREV, &temp);
269 	dev_info(&PIIX4_dev->dev,
270 		 "SMBus Host Controller at 0x%x, revision %d\n",
271 		 piix4_smba, temp);
272 
273 	return piix4_smba;
274 }
275 
276 static int piix4_setup_sb800(struct pci_dev *PIIX4_dev,
277 			     const struct pci_device_id *id, u8 aux)
278 {
279 	unsigned short piix4_smba;
280 	u8 smba_en_lo, smba_en_hi, smb_en, smb_en_status, port_sel;
281 	u8 i2ccfg, i2ccfg_offset = 0x10;
282 
283 	/* SB800 and later SMBus does not support forcing address */
284 	if (force || force_addr) {
285 		dev_err(&PIIX4_dev->dev, "SMBus does not support "
286 			"forcing address!\n");
287 		return -EINVAL;
288 	}
289 
290 	/* Determine the address of the SMBus areas */
291 	if ((PIIX4_dev->vendor == PCI_VENDOR_ID_AMD &&
292 	     PIIX4_dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS &&
293 	     PIIX4_dev->revision >= 0x41) ||
294 	    (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD &&
295 	     PIIX4_dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS &&
296 	     PIIX4_dev->revision >= 0x49))
297 		smb_en = 0x00;
298 	else
299 		smb_en = (aux) ? 0x28 : 0x2c;
300 
301 	mutex_lock(&piix4_mutex_sb800);
302 	outb_p(smb_en, SB800_PIIX4_SMB_IDX);
303 	smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
304 	outb_p(smb_en + 1, SB800_PIIX4_SMB_IDX);
305 	smba_en_hi = inb_p(SB800_PIIX4_SMB_IDX + 1);
306 	mutex_unlock(&piix4_mutex_sb800);
307 
308 	if (!smb_en) {
309 		smb_en_status = smba_en_lo & 0x10;
310 		piix4_smba = smba_en_hi << 8;
311 		if (aux)
312 			piix4_smba |= 0x20;
313 	} else {
314 		smb_en_status = smba_en_lo & 0x01;
315 		piix4_smba = ((smba_en_hi << 8) | smba_en_lo) & 0xffe0;
316 	}
317 
318 	if (!smb_en_status) {
319 		dev_err(&PIIX4_dev->dev,
320 			"SMBus Host Controller not enabled!\n");
321 		return -ENODEV;
322 	}
323 
324 	if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
325 		return -ENODEV;
326 
327 	if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
328 		dev_err(&PIIX4_dev->dev, "SMBus region 0x%x already in use!\n",
329 			piix4_smba);
330 		return -EBUSY;
331 	}
332 
333 	/* Aux SMBus does not support IRQ information */
334 	if (aux) {
335 		dev_info(&PIIX4_dev->dev,
336 			 "Auxiliary SMBus Host Controller at 0x%x\n",
337 			 piix4_smba);
338 		return piix4_smba;
339 	}
340 
341 	/* Request the SMBus I2C bus config region */
342 	if (!request_region(piix4_smba + i2ccfg_offset, 1, "i2ccfg")) {
343 		dev_err(&PIIX4_dev->dev, "SMBus I2C bus config region "
344 			"0x%x already in use!\n", piix4_smba + i2ccfg_offset);
345 		release_region(piix4_smba, SMBIOSIZE);
346 		return -EBUSY;
347 	}
348 	i2ccfg = inb_p(piix4_smba + i2ccfg_offset);
349 	release_region(piix4_smba + i2ccfg_offset, 1);
350 
351 	if (i2ccfg & 1)
352 		dev_dbg(&PIIX4_dev->dev, "Using IRQ for SMBus\n");
353 	else
354 		dev_dbg(&PIIX4_dev->dev, "Using SMI# for SMBus\n");
355 
356 	dev_info(&PIIX4_dev->dev,
357 		 "SMBus Host Controller at 0x%x, revision %d\n",
358 		 piix4_smba, i2ccfg >> 4);
359 
360 	/* Find which register is used for port selection */
361 	if (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD) {
362 		switch (PIIX4_dev->device) {
363 		case PCI_DEVICE_ID_AMD_KERNCZ_SMBUS:
364 			piix4_port_sel_sb800 = SB800_PIIX4_PORT_IDX_KERNCZ;
365 			piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK_KERNCZ;
366 			piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT_KERNCZ;
367 			break;
368 		case PCI_DEVICE_ID_AMD_HUDSON2_SMBUS:
369 		default:
370 			piix4_port_sel_sb800 = SB800_PIIX4_PORT_IDX_ALT;
371 			piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK;
372 			piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT;
373 			break;
374 		}
375 	} else {
376 		mutex_lock(&piix4_mutex_sb800);
377 		outb_p(SB800_PIIX4_PORT_IDX_SEL, SB800_PIIX4_SMB_IDX);
378 		port_sel = inb_p(SB800_PIIX4_SMB_IDX + 1);
379 		piix4_port_sel_sb800 = (port_sel & 0x01) ?
380 				       SB800_PIIX4_PORT_IDX_ALT :
381 				       SB800_PIIX4_PORT_IDX;
382 		piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK;
383 		piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT;
384 		mutex_unlock(&piix4_mutex_sb800);
385 	}
386 
387 	dev_info(&PIIX4_dev->dev,
388 		 "Using register 0x%02x for SMBus port selection\n",
389 		 (unsigned int)piix4_port_sel_sb800);
390 
391 	return piix4_smba;
392 }
393 
394 static int piix4_setup_aux(struct pci_dev *PIIX4_dev,
395 			   const struct pci_device_id *id,
396 			   unsigned short base_reg_addr)
397 {
398 	/* Set up auxiliary SMBus controllers found on some
399 	 * AMD chipsets e.g. SP5100 (SB700 derivative) */
400 
401 	unsigned short piix4_smba;
402 
403 	/* Read address of auxiliary SMBus controller */
404 	pci_read_config_word(PIIX4_dev, base_reg_addr, &piix4_smba);
405 	if ((piix4_smba & 1) == 0) {
406 		dev_dbg(&PIIX4_dev->dev,
407 			"Auxiliary SMBus controller not enabled\n");
408 		return -ENODEV;
409 	}
410 
411 	piix4_smba &= 0xfff0;
412 	if (piix4_smba == 0) {
413 		dev_dbg(&PIIX4_dev->dev,
414 			"Auxiliary SMBus base address uninitialized\n");
415 		return -ENODEV;
416 	}
417 
418 	if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
419 		return -ENODEV;
420 
421 	if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
422 		dev_err(&PIIX4_dev->dev, "Auxiliary SMBus region 0x%x "
423 			"already in use!\n", piix4_smba);
424 		return -EBUSY;
425 	}
426 
427 	dev_info(&PIIX4_dev->dev,
428 		 "Auxiliary SMBus Host Controller at 0x%x\n",
429 		 piix4_smba);
430 
431 	return piix4_smba;
432 }
433 
434 static int piix4_transaction(struct i2c_adapter *piix4_adapter)
435 {
436 	struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(piix4_adapter);
437 	unsigned short piix4_smba = adapdata->smba;
438 	int temp;
439 	int result = 0;
440 	int timeout = 0;
441 
442 	dev_dbg(&piix4_adapter->dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
443 		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
444 		inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
445 		inb_p(SMBHSTDAT1));
446 
447 	/* Make sure the SMBus host is ready to start transmitting */
448 	if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
449 		dev_dbg(&piix4_adapter->dev, "SMBus busy (%02x). "
450 			"Resetting...\n", temp);
451 		outb_p(temp, SMBHSTSTS);
452 		if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
453 			dev_err(&piix4_adapter->dev, "Failed! (%02x)\n", temp);
454 			return -EBUSY;
455 		} else {
456 			dev_dbg(&piix4_adapter->dev, "Successful!\n");
457 		}
458 	}
459 
460 	/* start the transaction by setting bit 6 */
461 	outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT);
462 
463 	/* We will always wait for a fraction of a second! (See PIIX4 docs errata) */
464 	if (srvrworks_csb5_delay) /* Extra delay for SERVERWORKS_CSB5 */
465 		msleep(2);
466 	else
467 		msleep(1);
468 
469 	while ((++timeout < MAX_TIMEOUT) &&
470 	       ((temp = inb_p(SMBHSTSTS)) & 0x01))
471 		msleep(1);
472 
473 	/* If the SMBus is still busy, we give up */
474 	if (timeout == MAX_TIMEOUT) {
475 		dev_err(&piix4_adapter->dev, "SMBus Timeout!\n");
476 		result = -ETIMEDOUT;
477 	}
478 
479 	if (temp & 0x10) {
480 		result = -EIO;
481 		dev_err(&piix4_adapter->dev, "Error: Failed bus transaction\n");
482 	}
483 
484 	if (temp & 0x08) {
485 		result = -EIO;
486 		dev_dbg(&piix4_adapter->dev, "Bus collision! SMBus may be "
487 			"locked until next hard reset. (sorry!)\n");
488 		/* Clock stops and slave is stuck in mid-transmission */
489 	}
490 
491 	if (temp & 0x04) {
492 		result = -ENXIO;
493 		dev_dbg(&piix4_adapter->dev, "Error: no response!\n");
494 	}
495 
496 	if (inb_p(SMBHSTSTS) != 0x00)
497 		outb_p(inb(SMBHSTSTS), SMBHSTSTS);
498 
499 	if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
500 		dev_err(&piix4_adapter->dev, "Failed reset at end of "
501 			"transaction (%02x)\n", temp);
502 	}
503 	dev_dbg(&piix4_adapter->dev, "Transaction (post): CNT=%02x, CMD=%02x, "
504 		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
505 		inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
506 		inb_p(SMBHSTDAT1));
507 	return result;
508 }
509 
510 /* Return negative errno on error. */
511 static s32 piix4_access(struct i2c_adapter * adap, u16 addr,
512 		 unsigned short flags, char read_write,
513 		 u8 command, int size, union i2c_smbus_data * data)
514 {
515 	struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
516 	unsigned short piix4_smba = adapdata->smba;
517 	int i, len;
518 	int status;
519 
520 	switch (size) {
521 	case I2C_SMBUS_QUICK:
522 		outb_p((addr << 1) | read_write,
523 		       SMBHSTADD);
524 		size = PIIX4_QUICK;
525 		break;
526 	case I2C_SMBUS_BYTE:
527 		outb_p((addr << 1) | read_write,
528 		       SMBHSTADD);
529 		if (read_write == I2C_SMBUS_WRITE)
530 			outb_p(command, SMBHSTCMD);
531 		size = PIIX4_BYTE;
532 		break;
533 	case I2C_SMBUS_BYTE_DATA:
534 		outb_p((addr << 1) | read_write,
535 		       SMBHSTADD);
536 		outb_p(command, SMBHSTCMD);
537 		if (read_write == I2C_SMBUS_WRITE)
538 			outb_p(data->byte, SMBHSTDAT0);
539 		size = PIIX4_BYTE_DATA;
540 		break;
541 	case I2C_SMBUS_WORD_DATA:
542 		outb_p((addr << 1) | read_write,
543 		       SMBHSTADD);
544 		outb_p(command, SMBHSTCMD);
545 		if (read_write == I2C_SMBUS_WRITE) {
546 			outb_p(data->word & 0xff, SMBHSTDAT0);
547 			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
548 		}
549 		size = PIIX4_WORD_DATA;
550 		break;
551 	case I2C_SMBUS_BLOCK_DATA:
552 		outb_p((addr << 1) | read_write,
553 		       SMBHSTADD);
554 		outb_p(command, SMBHSTCMD);
555 		if (read_write == I2C_SMBUS_WRITE) {
556 			len = data->block[0];
557 			if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
558 				return -EINVAL;
559 			outb_p(len, SMBHSTDAT0);
560 			inb_p(SMBHSTCNT);	/* Reset SMBBLKDAT */
561 			for (i = 1; i <= len; i++)
562 				outb_p(data->block[i], SMBBLKDAT);
563 		}
564 		size = PIIX4_BLOCK_DATA;
565 		break;
566 	default:
567 		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
568 		return -EOPNOTSUPP;
569 	}
570 
571 	outb_p((size & 0x1C) + (ENABLE_INT9 & 1), SMBHSTCNT);
572 
573 	status = piix4_transaction(adap);
574 	if (status)
575 		return status;
576 
577 	if ((read_write == I2C_SMBUS_WRITE) || (size == PIIX4_QUICK))
578 		return 0;
579 
580 
581 	switch (size) {
582 	case PIIX4_BYTE:
583 	case PIIX4_BYTE_DATA:
584 		data->byte = inb_p(SMBHSTDAT0);
585 		break;
586 	case PIIX4_WORD_DATA:
587 		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
588 		break;
589 	case PIIX4_BLOCK_DATA:
590 		data->block[0] = inb_p(SMBHSTDAT0);
591 		if (data->block[0] == 0 || data->block[0] > I2C_SMBUS_BLOCK_MAX)
592 			return -EPROTO;
593 		inb_p(SMBHSTCNT);	/* Reset SMBBLKDAT */
594 		for (i = 1; i <= data->block[0]; i++)
595 			data->block[i] = inb_p(SMBBLKDAT);
596 		break;
597 	}
598 	return 0;
599 }
600 
601 static uint8_t piix4_imc_read(uint8_t idx)
602 {
603 	outb_p(idx, KERNCZ_IMC_IDX);
604 	return inb_p(KERNCZ_IMC_DATA);
605 }
606 
607 static void piix4_imc_write(uint8_t idx, uint8_t value)
608 {
609 	outb_p(idx, KERNCZ_IMC_IDX);
610 	outb_p(value, KERNCZ_IMC_DATA);
611 }
612 
613 static int piix4_imc_sleep(void)
614 {
615 	int timeout = MAX_TIMEOUT;
616 
617 	if (!request_muxed_region(KERNCZ_IMC_IDX, 2, "smbus_kerncz_imc"))
618 		return -EBUSY;
619 
620 	/* clear response register */
621 	piix4_imc_write(0x82, 0x00);
622 	/* request ownership flag */
623 	piix4_imc_write(0x83, 0xB4);
624 	/* kick off IMC Mailbox command 96 */
625 	piix4_imc_write(0x80, 0x96);
626 
627 	while (timeout--) {
628 		if (piix4_imc_read(0x82) == 0xfa) {
629 			release_region(KERNCZ_IMC_IDX, 2);
630 			return 0;
631 		}
632 		usleep_range(1000, 2000);
633 	}
634 
635 	release_region(KERNCZ_IMC_IDX, 2);
636 	return -ETIMEDOUT;
637 }
638 
639 static void piix4_imc_wakeup(void)
640 {
641 	int timeout = MAX_TIMEOUT;
642 
643 	if (!request_muxed_region(KERNCZ_IMC_IDX, 2, "smbus_kerncz_imc"))
644 		return;
645 
646 	/* clear response register */
647 	piix4_imc_write(0x82, 0x00);
648 	/* release ownership flag */
649 	piix4_imc_write(0x83, 0xB5);
650 	/* kick off IMC Mailbox command 96 */
651 	piix4_imc_write(0x80, 0x96);
652 
653 	while (timeout--) {
654 		if (piix4_imc_read(0x82) == 0xfa)
655 			break;
656 		usleep_range(1000, 2000);
657 	}
658 
659 	release_region(KERNCZ_IMC_IDX, 2);
660 }
661 
662 /*
663  * Handles access to multiple SMBus ports on the SB800.
664  * The port is selected by bits 2:1 of the smb_en register (0x2c).
665  * Returns negative errno on error.
666  *
667  * Note: The selected port must be returned to the initial selection to avoid
668  * problems on certain systems.
669  */
670 static s32 piix4_access_sb800(struct i2c_adapter *adap, u16 addr,
671 		 unsigned short flags, char read_write,
672 		 u8 command, int size, union i2c_smbus_data *data)
673 {
674 	struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
675 	unsigned short piix4_smba = adapdata->smba;
676 	int retries = MAX_TIMEOUT;
677 	int smbslvcnt;
678 	u8 smba_en_lo;
679 	u8 port;
680 	int retval;
681 
682 	mutex_lock(&piix4_mutex_sb800);
683 
684 	/* Request the SMBUS semaphore, avoid conflicts with the IMC */
685 	smbslvcnt  = inb_p(SMBSLVCNT);
686 	do {
687 		outb_p(smbslvcnt | 0x10, SMBSLVCNT);
688 
689 		/* Check the semaphore status */
690 		smbslvcnt  = inb_p(SMBSLVCNT);
691 		if (smbslvcnt & 0x10)
692 			break;
693 
694 		usleep_range(1000, 2000);
695 	} while (--retries);
696 	/* SMBus is still owned by the IMC, we give up */
697 	if (!retries) {
698 		mutex_unlock(&piix4_mutex_sb800);
699 		return -EBUSY;
700 	}
701 
702 	/*
703 	 * Notify the IMC (Integrated Micro Controller) if required.
704 	 * Among other responsibilities, the IMC is in charge of monitoring
705 	 * the System fans and temperature sensors, and act accordingly.
706 	 * All this is done through SMBus and can/will collide
707 	 * with our transactions if they are long (BLOCK_DATA).
708 	 * Therefore we need to request the ownership flag during those
709 	 * transactions.
710 	 */
711 	if ((size == I2C_SMBUS_BLOCK_DATA) && adapdata->notify_imc) {
712 		int ret;
713 
714 		ret = piix4_imc_sleep();
715 		switch (ret) {
716 		case -EBUSY:
717 			dev_warn(&adap->dev,
718 				 "IMC base address index region 0x%x already in use.\n",
719 				 KERNCZ_IMC_IDX);
720 			break;
721 		case -ETIMEDOUT:
722 			dev_warn(&adap->dev,
723 				 "Failed to communicate with the IMC.\n");
724 			break;
725 		default:
726 			break;
727 		}
728 
729 		/* If IMC communication fails do not retry */
730 		if (ret) {
731 			dev_warn(&adap->dev,
732 				 "Continuing without IMC notification.\n");
733 			adapdata->notify_imc = false;
734 		}
735 	}
736 
737 	outb_p(piix4_port_sel_sb800, SB800_PIIX4_SMB_IDX);
738 	smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
739 
740 	port = adapdata->port;
741 	if ((smba_en_lo & piix4_port_mask_sb800) != port)
742 		outb_p((smba_en_lo & ~piix4_port_mask_sb800) | port,
743 		       SB800_PIIX4_SMB_IDX + 1);
744 
745 	retval = piix4_access(adap, addr, flags, read_write,
746 			      command, size, data);
747 
748 	outb_p(smba_en_lo, SB800_PIIX4_SMB_IDX + 1);
749 
750 	/* Release the semaphore */
751 	outb_p(smbslvcnt | 0x20, SMBSLVCNT);
752 
753 	if ((size == I2C_SMBUS_BLOCK_DATA) && adapdata->notify_imc)
754 		piix4_imc_wakeup();
755 
756 	mutex_unlock(&piix4_mutex_sb800);
757 
758 	return retval;
759 }
760 
761 static u32 piix4_func(struct i2c_adapter *adapter)
762 {
763 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
764 	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
765 	    I2C_FUNC_SMBUS_BLOCK_DATA;
766 }
767 
768 static const struct i2c_algorithm smbus_algorithm = {
769 	.smbus_xfer	= piix4_access,
770 	.functionality	= piix4_func,
771 };
772 
773 static const struct i2c_algorithm piix4_smbus_algorithm_sb800 = {
774 	.smbus_xfer	= piix4_access_sb800,
775 	.functionality	= piix4_func,
776 };
777 
778 static const struct pci_device_id piix4_ids[] = {
779 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3) },
780 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443MX_3) },
781 	{ PCI_DEVICE(PCI_VENDOR_ID_EFAR, PCI_DEVICE_ID_EFAR_SLC90E66_3) },
782 	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP200_SMBUS) },
783 	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP300_SMBUS) },
784 	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS) },
785 	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS) },
786 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_HUDSON2_SMBUS) },
787 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) },
788 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
789 		     PCI_DEVICE_ID_SERVERWORKS_OSB4) },
790 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
791 		     PCI_DEVICE_ID_SERVERWORKS_CSB5) },
792 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
793 		     PCI_DEVICE_ID_SERVERWORKS_CSB6) },
794 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
795 		     PCI_DEVICE_ID_SERVERWORKS_HT1000SB) },
796 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
797 		     PCI_DEVICE_ID_SERVERWORKS_HT1100LD) },
798 	{ 0, }
799 };
800 
801 MODULE_DEVICE_TABLE (pci, piix4_ids);
802 
803 static struct i2c_adapter *piix4_main_adapters[PIIX4_MAX_ADAPTERS];
804 static struct i2c_adapter *piix4_aux_adapter;
805 
806 static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba,
807 			     bool sb800_main, u8 port, bool notify_imc,
808 			     const char *name, struct i2c_adapter **padap)
809 {
810 	struct i2c_adapter *adap;
811 	struct i2c_piix4_adapdata *adapdata;
812 	int retval;
813 
814 	adap = kzalloc(sizeof(*adap), GFP_KERNEL);
815 	if (adap == NULL) {
816 		release_region(smba, SMBIOSIZE);
817 		return -ENOMEM;
818 	}
819 
820 	adap->owner = THIS_MODULE;
821 	adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
822 	adap->algo = sb800_main ? &piix4_smbus_algorithm_sb800
823 				: &smbus_algorithm;
824 
825 	adapdata = kzalloc(sizeof(*adapdata), GFP_KERNEL);
826 	if (adapdata == NULL) {
827 		kfree(adap);
828 		release_region(smba, SMBIOSIZE);
829 		return -ENOMEM;
830 	}
831 
832 	adapdata->smba = smba;
833 	adapdata->sb800_main = sb800_main;
834 	adapdata->port = port << piix4_port_shift_sb800;
835 	adapdata->notify_imc = notify_imc;
836 
837 	/* set up the sysfs linkage to our parent device */
838 	adap->dev.parent = &dev->dev;
839 
840 	snprintf(adap->name, sizeof(adap->name),
841 		"SMBus PIIX4 adapter%s at %04x", name, smba);
842 
843 	i2c_set_adapdata(adap, adapdata);
844 
845 	retval = i2c_add_adapter(adap);
846 	if (retval) {
847 		kfree(adapdata);
848 		kfree(adap);
849 		release_region(smba, SMBIOSIZE);
850 		return retval;
851 	}
852 
853 	*padap = adap;
854 	return 0;
855 }
856 
857 static int piix4_add_adapters_sb800(struct pci_dev *dev, unsigned short smba,
858 				    bool notify_imc)
859 {
860 	struct i2c_piix4_adapdata *adapdata;
861 	int port;
862 	int retval;
863 
864 	for (port = 0; port < PIIX4_MAX_ADAPTERS; port++) {
865 		retval = piix4_add_adapter(dev, smba, true, port, notify_imc,
866 					   piix4_main_port_names_sb800[port],
867 					   &piix4_main_adapters[port]);
868 		if (retval < 0)
869 			goto error;
870 	}
871 
872 	return retval;
873 
874 error:
875 	dev_err(&dev->dev,
876 		"Error setting up SB800 adapters. Unregistering!\n");
877 	while (--port >= 0) {
878 		adapdata = i2c_get_adapdata(piix4_main_adapters[port]);
879 		if (adapdata->smba) {
880 			i2c_del_adapter(piix4_main_adapters[port]);
881 			kfree(adapdata);
882 			kfree(piix4_main_adapters[port]);
883 			piix4_main_adapters[port] = NULL;
884 		}
885 	}
886 
887 	return retval;
888 }
889 
890 static int piix4_probe(struct pci_dev *dev, const struct pci_device_id *id)
891 {
892 	int retval;
893 	bool is_sb800 = false;
894 
895 	if ((dev->vendor == PCI_VENDOR_ID_ATI &&
896 	     dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS &&
897 	     dev->revision >= 0x40) ||
898 	    dev->vendor == PCI_VENDOR_ID_AMD) {
899 		bool notify_imc = false;
900 		is_sb800 = true;
901 
902 		if (!request_region(SB800_PIIX4_SMB_IDX, 2, "smba_idx")) {
903 			dev_err(&dev->dev,
904 			"SMBus base address index region 0x%x already in use!\n",
905 			SB800_PIIX4_SMB_IDX);
906 			return -EBUSY;
907 		}
908 
909 		if (dev->vendor == PCI_VENDOR_ID_AMD &&
910 		    dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) {
911 			u8 imc;
912 
913 			/*
914 			 * Detect if IMC is active or not, this method is
915 			 * described on coreboot's AMD IMC notes
916 			 */
917 			pci_bus_read_config_byte(dev->bus, PCI_DEVFN(0x14, 3),
918 						 0x40, &imc);
919 			if (imc & 0x80)
920 				notify_imc = true;
921 		}
922 
923 		/* base address location etc changed in SB800 */
924 		retval = piix4_setup_sb800(dev, id, 0);
925 		if (retval < 0) {
926 			release_region(SB800_PIIX4_SMB_IDX, 2);
927 			return retval;
928 		}
929 
930 		/*
931 		 * Try to register multiplexed main SMBus adapter,
932 		 * give up if we can't
933 		 */
934 		retval = piix4_add_adapters_sb800(dev, retval, notify_imc);
935 		if (retval < 0) {
936 			release_region(SB800_PIIX4_SMB_IDX, 2);
937 			return retval;
938 		}
939 	} else {
940 		retval = piix4_setup(dev, id);
941 		if (retval < 0)
942 			return retval;
943 
944 		/* Try to register main SMBus adapter, give up if we can't */
945 		retval = piix4_add_adapter(dev, retval, false, 0, false, "",
946 					   &piix4_main_adapters[0]);
947 		if (retval < 0)
948 			return retval;
949 	}
950 
951 	/* Check for auxiliary SMBus on some AMD chipsets */
952 	retval = -ENODEV;
953 
954 	if (dev->vendor == PCI_VENDOR_ID_ATI &&
955 	    dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS) {
956 		if (dev->revision < 0x40) {
957 			retval = piix4_setup_aux(dev, id, 0x58);
958 		} else {
959 			/* SB800 added aux bus too */
960 			retval = piix4_setup_sb800(dev, id, 1);
961 		}
962 	}
963 
964 	if (dev->vendor == PCI_VENDOR_ID_AMD &&
965 	    dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS) {
966 		retval = piix4_setup_sb800(dev, id, 1);
967 	}
968 
969 	if (retval > 0) {
970 		/* Try to add the aux adapter if it exists,
971 		 * piix4_add_adapter will clean up if this fails */
972 		piix4_add_adapter(dev, retval, false, 0, false,
973 				  is_sb800 ? piix4_aux_port_name_sb800 : "",
974 				  &piix4_aux_adapter);
975 	}
976 
977 	return 0;
978 }
979 
980 static void piix4_adap_remove(struct i2c_adapter *adap)
981 {
982 	struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
983 
984 	if (adapdata->smba) {
985 		i2c_del_adapter(adap);
986 		if (adapdata->port == (0 << piix4_port_shift_sb800)) {
987 			release_region(adapdata->smba, SMBIOSIZE);
988 			if (adapdata->sb800_main)
989 				release_region(SB800_PIIX4_SMB_IDX, 2);
990 		}
991 		kfree(adapdata);
992 		kfree(adap);
993 	}
994 }
995 
996 static void piix4_remove(struct pci_dev *dev)
997 {
998 	int port = PIIX4_MAX_ADAPTERS;
999 
1000 	while (--port >= 0) {
1001 		if (piix4_main_adapters[port]) {
1002 			piix4_adap_remove(piix4_main_adapters[port]);
1003 			piix4_main_adapters[port] = NULL;
1004 		}
1005 	}
1006 
1007 	if (piix4_aux_adapter) {
1008 		piix4_adap_remove(piix4_aux_adapter);
1009 		piix4_aux_adapter = NULL;
1010 	}
1011 }
1012 
1013 static struct pci_driver piix4_driver = {
1014 	.name		= "piix4_smbus",
1015 	.id_table	= piix4_ids,
1016 	.probe		= piix4_probe,
1017 	.remove		= piix4_remove,
1018 };
1019 
1020 module_pci_driver(piix4_driver);
1021 
1022 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
1023 		"Philip Edelbrock <phil@netroedge.com>");
1024 MODULE_DESCRIPTION("PIIX4 SMBus driver");
1025 MODULE_LICENSE("GPL");
1026