xref: /openbmc/linux/drivers/i2c/busses/i2c-piix4.c (revision 3213486f)
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 
44 
45 /* PIIX4 SMBus address offsets */
46 #define SMBHSTSTS	(0 + piix4_smba)
47 #define SMBHSLVSTS	(1 + piix4_smba)
48 #define SMBHSTCNT	(2 + piix4_smba)
49 #define SMBHSTCMD	(3 + piix4_smba)
50 #define SMBHSTADD	(4 + piix4_smba)
51 #define SMBHSTDAT0	(5 + piix4_smba)
52 #define SMBHSTDAT1	(6 + piix4_smba)
53 #define SMBBLKDAT	(7 + piix4_smba)
54 #define SMBSLVCNT	(8 + piix4_smba)
55 #define SMBSHDWCMD	(9 + piix4_smba)
56 #define SMBSLVEVT	(0xA + piix4_smba)
57 #define SMBSLVDAT	(0xC + piix4_smba)
58 
59 /* count for request_region */
60 #define SMBIOSIZE	9
61 
62 /* PCI Address Constants */
63 #define SMBBA		0x090
64 #define SMBHSTCFG	0x0D2
65 #define SMBSLVC		0x0D3
66 #define SMBSHDW1	0x0D4
67 #define SMBSHDW2	0x0D5
68 #define SMBREV		0x0D6
69 
70 /* Other settings */
71 #define MAX_TIMEOUT	500
72 #define  ENABLE_INT9	0
73 
74 /* PIIX4 constants */
75 #define PIIX4_QUICK		0x00
76 #define PIIX4_BYTE		0x04
77 #define PIIX4_BYTE_DATA		0x08
78 #define PIIX4_WORD_DATA		0x0C
79 #define PIIX4_BLOCK_DATA	0x14
80 
81 /* Multi-port constants */
82 #define PIIX4_MAX_ADAPTERS 4
83 
84 /* SB800 constants */
85 #define SB800_PIIX4_SMB_IDX		0xcd6
86 
87 #define KERNCZ_IMC_IDX			0x3e
88 #define KERNCZ_IMC_DATA			0x3f
89 
90 /*
91  * SB800 port is selected by bits 2:1 of the smb_en register (0x2c)
92  * or the smb_sel register (0x2e), depending on bit 0 of register 0x2f.
93  * Hudson-2/Bolton port is always selected by bits 2:1 of register 0x2f.
94  */
95 #define SB800_PIIX4_PORT_IDX		0x2c
96 #define SB800_PIIX4_PORT_IDX_ALT	0x2e
97 #define SB800_PIIX4_PORT_IDX_SEL	0x2f
98 #define SB800_PIIX4_PORT_IDX_MASK	0x06
99 #define SB800_PIIX4_PORT_IDX_SHIFT	1
100 
101 /* On kerncz, SmBus0Sel is at bit 20:19 of PMx00 DecodeEn */
102 #define SB800_PIIX4_PORT_IDX_KERNCZ		0x02
103 #define SB800_PIIX4_PORT_IDX_MASK_KERNCZ	0x18
104 #define SB800_PIIX4_PORT_IDX_SHIFT_KERNCZ	3
105 
106 /* insmod parameters */
107 
108 /* If force is set to anything different from 0, we forcibly enable the
109    PIIX4. DANGEROUS! */
110 static int force;
111 module_param (force, int, 0);
112 MODULE_PARM_DESC(force, "Forcibly enable the PIIX4. DANGEROUS!");
113 
114 /* If force_addr is set to anything different from 0, we forcibly enable
115    the PIIX4 at the given address. VERY DANGEROUS! */
116 static int force_addr;
117 module_param_hw(force_addr, int, ioport, 0);
118 MODULE_PARM_DESC(force_addr,
119 		 "Forcibly enable the PIIX4 at the given address. "
120 		 "EXTREMELY DANGEROUS!");
121 
122 static int srvrworks_csb5_delay;
123 static struct pci_driver piix4_driver;
124 
125 static const struct dmi_system_id piix4_dmi_blacklist[] = {
126 	{
127 		.ident = "Sapphire AM2RD790",
128 		.matches = {
129 			DMI_MATCH(DMI_BOARD_VENDOR, "SAPPHIRE Inc."),
130 			DMI_MATCH(DMI_BOARD_NAME, "PC-AM2RD790"),
131 		},
132 	},
133 	{
134 		.ident = "DFI Lanparty UT 790FX",
135 		.matches = {
136 			DMI_MATCH(DMI_BOARD_VENDOR, "DFI Inc."),
137 			DMI_MATCH(DMI_BOARD_NAME, "LP UT 790FX"),
138 		},
139 	},
140 	{ }
141 };
142 
143 /* The IBM entry is in a separate table because we only check it
144    on Intel-based systems */
145 static const struct dmi_system_id piix4_dmi_ibm[] = {
146 	{
147 		.ident = "IBM",
148 		.matches = { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
149 	},
150 	{ },
151 };
152 
153 /*
154  * SB800 globals
155  */
156 static u8 piix4_port_sel_sb800;
157 static u8 piix4_port_mask_sb800;
158 static u8 piix4_port_shift_sb800;
159 static const char *piix4_main_port_names_sb800[PIIX4_MAX_ADAPTERS] = {
160 	" port 0", " port 2", " port 3", " port 4"
161 };
162 static const char *piix4_aux_port_name_sb800 = " port 1";
163 
164 struct i2c_piix4_adapdata {
165 	unsigned short smba;
166 
167 	/* SB800 */
168 	bool sb800_main;
169 	bool notify_imc;
170 	u8 port;		/* Port number, shifted */
171 };
172 
173 static int piix4_setup(struct pci_dev *PIIX4_dev,
174 		       const struct pci_device_id *id)
175 {
176 	unsigned char temp;
177 	unsigned short piix4_smba;
178 
179 	if ((PIIX4_dev->vendor == PCI_VENDOR_ID_SERVERWORKS) &&
180 	    (PIIX4_dev->device == PCI_DEVICE_ID_SERVERWORKS_CSB5))
181 		srvrworks_csb5_delay = 1;
182 
183 	/* On some motherboards, it was reported that accessing the SMBus
184 	   caused severe hardware problems */
185 	if (dmi_check_system(piix4_dmi_blacklist)) {
186 		dev_err(&PIIX4_dev->dev,
187 			"Accessing the SMBus on this system is unsafe!\n");
188 		return -EPERM;
189 	}
190 
191 	/* Don't access SMBus on IBM systems which get corrupted eeproms */
192 	if (dmi_check_system(piix4_dmi_ibm) &&
193 			PIIX4_dev->vendor == PCI_VENDOR_ID_INTEL) {
194 		dev_err(&PIIX4_dev->dev, "IBM system detected; this module "
195 			"may corrupt your serial eeprom! Refusing to load "
196 			"module!\n");
197 		return -EPERM;
198 	}
199 
200 	/* Determine the address of the SMBus areas */
201 	if (force_addr) {
202 		piix4_smba = force_addr & 0xfff0;
203 		force = 0;
204 	} else {
205 		pci_read_config_word(PIIX4_dev, SMBBA, &piix4_smba);
206 		piix4_smba &= 0xfff0;
207 		if(piix4_smba == 0) {
208 			dev_err(&PIIX4_dev->dev, "SMBus base address "
209 				"uninitialized - upgrade BIOS or use "
210 				"force_addr=0xaddr\n");
211 			return -ENODEV;
212 		}
213 	}
214 
215 	if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
216 		return -ENODEV;
217 
218 	if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
219 		dev_err(&PIIX4_dev->dev, "SMBus region 0x%x already in use!\n",
220 			piix4_smba);
221 		return -EBUSY;
222 	}
223 
224 	pci_read_config_byte(PIIX4_dev, SMBHSTCFG, &temp);
225 
226 	/* If force_addr is set, we program the new address here. Just to make
227 	   sure, we disable the PIIX4 first. */
228 	if (force_addr) {
229 		pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp & 0xfe);
230 		pci_write_config_word(PIIX4_dev, SMBBA, piix4_smba);
231 		pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp | 0x01);
232 		dev_info(&PIIX4_dev->dev, "WARNING: SMBus interface set to "
233 			"new address %04x!\n", piix4_smba);
234 	} else if ((temp & 1) == 0) {
235 		if (force) {
236 			/* This should never need to be done, but has been
237 			 * noted that many Dell machines have the SMBus
238 			 * interface on the PIIX4 disabled!? NOTE: This assumes
239 			 * I/O space and other allocations WERE done by the
240 			 * Bios!  Don't complain if your hardware does weird
241 			 * things after enabling this. :') Check for Bios
242 			 * updates before resorting to this.
243 			 */
244 			pci_write_config_byte(PIIX4_dev, SMBHSTCFG,
245 					      temp | 1);
246 			dev_notice(&PIIX4_dev->dev,
247 				   "WARNING: SMBus interface has been FORCEFULLY ENABLED!\n");
248 		} else {
249 			dev_err(&PIIX4_dev->dev,
250 				"SMBus Host Controller not enabled!\n");
251 			release_region(piix4_smba, SMBIOSIZE);
252 			return -ENODEV;
253 		}
254 	}
255 
256 	if (((temp & 0x0E) == 8) || ((temp & 0x0E) == 2))
257 		dev_dbg(&PIIX4_dev->dev, "Using IRQ for SMBus\n");
258 	else if ((temp & 0x0E) == 0)
259 		dev_dbg(&PIIX4_dev->dev, "Using SMI# for SMBus\n");
260 	else
261 		dev_err(&PIIX4_dev->dev, "Illegal Interrupt configuration "
262 			"(or code out of date)!\n");
263 
264 	pci_read_config_byte(PIIX4_dev, SMBREV, &temp);
265 	dev_info(&PIIX4_dev->dev,
266 		 "SMBus Host Controller at 0x%x, revision %d\n",
267 		 piix4_smba, temp);
268 
269 	return piix4_smba;
270 }
271 
272 static int piix4_setup_sb800(struct pci_dev *PIIX4_dev,
273 			     const struct pci_device_id *id, u8 aux)
274 {
275 	unsigned short piix4_smba;
276 	u8 smba_en_lo, smba_en_hi, smb_en, smb_en_status, port_sel;
277 	u8 i2ccfg, i2ccfg_offset = 0x10;
278 
279 	/* SB800 and later SMBus does not support forcing address */
280 	if (force || force_addr) {
281 		dev_err(&PIIX4_dev->dev, "SMBus does not support "
282 			"forcing address!\n");
283 		return -EINVAL;
284 	}
285 
286 	/* Determine the address of the SMBus areas */
287 	if ((PIIX4_dev->vendor == PCI_VENDOR_ID_AMD &&
288 	     PIIX4_dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS &&
289 	     PIIX4_dev->revision >= 0x41) ||
290 	    (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD &&
291 	     PIIX4_dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS &&
292 	     PIIX4_dev->revision >= 0x49))
293 		smb_en = 0x00;
294 	else
295 		smb_en = (aux) ? 0x28 : 0x2c;
296 
297 	if (!request_muxed_region(SB800_PIIX4_SMB_IDX, 2, "sb800_piix4_smb")) {
298 		dev_err(&PIIX4_dev->dev,
299 			"SMB base address index region 0x%x already in use.\n",
300 			SB800_PIIX4_SMB_IDX);
301 		return -EBUSY;
302 	}
303 
304 	outb_p(smb_en, SB800_PIIX4_SMB_IDX);
305 	smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
306 	outb_p(smb_en + 1, SB800_PIIX4_SMB_IDX);
307 	smba_en_hi = inb_p(SB800_PIIX4_SMB_IDX + 1);
308 
309 	release_region(SB800_PIIX4_SMB_IDX, 2);
310 
311 	if (!smb_en) {
312 		smb_en_status = smba_en_lo & 0x10;
313 		piix4_smba = smba_en_hi << 8;
314 		if (aux)
315 			piix4_smba |= 0x20;
316 	} else {
317 		smb_en_status = smba_en_lo & 0x01;
318 		piix4_smba = ((smba_en_hi << 8) | smba_en_lo) & 0xffe0;
319 	}
320 
321 	if (!smb_en_status) {
322 		dev_err(&PIIX4_dev->dev,
323 			"SMBus Host Controller not enabled!\n");
324 		return -ENODEV;
325 	}
326 
327 	if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
328 		return -ENODEV;
329 
330 	if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
331 		dev_err(&PIIX4_dev->dev, "SMBus region 0x%x already in use!\n",
332 			piix4_smba);
333 		return -EBUSY;
334 	}
335 
336 	/* Aux SMBus does not support IRQ information */
337 	if (aux) {
338 		dev_info(&PIIX4_dev->dev,
339 			 "Auxiliary SMBus Host Controller at 0x%x\n",
340 			 piix4_smba);
341 		return piix4_smba;
342 	}
343 
344 	/* Request the SMBus I2C bus config region */
345 	if (!request_region(piix4_smba + i2ccfg_offset, 1, "i2ccfg")) {
346 		dev_err(&PIIX4_dev->dev, "SMBus I2C bus config region "
347 			"0x%x already in use!\n", piix4_smba + i2ccfg_offset);
348 		release_region(piix4_smba, SMBIOSIZE);
349 		return -EBUSY;
350 	}
351 	i2ccfg = inb_p(piix4_smba + i2ccfg_offset);
352 	release_region(piix4_smba + i2ccfg_offset, 1);
353 
354 	if (i2ccfg & 1)
355 		dev_dbg(&PIIX4_dev->dev, "Using IRQ for SMBus\n");
356 	else
357 		dev_dbg(&PIIX4_dev->dev, "Using SMI# for SMBus\n");
358 
359 	dev_info(&PIIX4_dev->dev,
360 		 "SMBus Host Controller at 0x%x, revision %d\n",
361 		 piix4_smba, i2ccfg >> 4);
362 
363 	/* Find which register is used for port selection */
364 	if (PIIX4_dev->vendor == PCI_VENDOR_ID_AMD) {
365 		switch (PIIX4_dev->device) {
366 		case PCI_DEVICE_ID_AMD_KERNCZ_SMBUS:
367 			piix4_port_sel_sb800 = SB800_PIIX4_PORT_IDX_KERNCZ;
368 			piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK_KERNCZ;
369 			piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT_KERNCZ;
370 			break;
371 		case PCI_DEVICE_ID_AMD_HUDSON2_SMBUS:
372 		default:
373 			piix4_port_sel_sb800 = SB800_PIIX4_PORT_IDX_ALT;
374 			piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK;
375 			piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT;
376 			break;
377 		}
378 	} else {
379 		if (!request_muxed_region(SB800_PIIX4_SMB_IDX, 2,
380 					  "sb800_piix4_smb")) {
381 			release_region(piix4_smba, SMBIOSIZE);
382 			return -EBUSY;
383 		}
384 
385 		outb_p(SB800_PIIX4_PORT_IDX_SEL, SB800_PIIX4_SMB_IDX);
386 		port_sel = inb_p(SB800_PIIX4_SMB_IDX + 1);
387 		piix4_port_sel_sb800 = (port_sel & 0x01) ?
388 				       SB800_PIIX4_PORT_IDX_ALT :
389 				       SB800_PIIX4_PORT_IDX;
390 		piix4_port_mask_sb800 = SB800_PIIX4_PORT_IDX_MASK;
391 		piix4_port_shift_sb800 = SB800_PIIX4_PORT_IDX_SHIFT;
392 		release_region(SB800_PIIX4_SMB_IDX, 2);
393 	}
394 
395 	dev_info(&PIIX4_dev->dev,
396 		 "Using register 0x%02x for SMBus port selection\n",
397 		 (unsigned int)piix4_port_sel_sb800);
398 
399 	return piix4_smba;
400 }
401 
402 static int piix4_setup_aux(struct pci_dev *PIIX4_dev,
403 			   const struct pci_device_id *id,
404 			   unsigned short base_reg_addr)
405 {
406 	/* Set up auxiliary SMBus controllers found on some
407 	 * AMD chipsets e.g. SP5100 (SB700 derivative) */
408 
409 	unsigned short piix4_smba;
410 
411 	/* Read address of auxiliary SMBus controller */
412 	pci_read_config_word(PIIX4_dev, base_reg_addr, &piix4_smba);
413 	if ((piix4_smba & 1) == 0) {
414 		dev_dbg(&PIIX4_dev->dev,
415 			"Auxiliary SMBus controller not enabled\n");
416 		return -ENODEV;
417 	}
418 
419 	piix4_smba &= 0xfff0;
420 	if (piix4_smba == 0) {
421 		dev_dbg(&PIIX4_dev->dev,
422 			"Auxiliary SMBus base address uninitialized\n");
423 		return -ENODEV;
424 	}
425 
426 	if (acpi_check_region(piix4_smba, SMBIOSIZE, piix4_driver.name))
427 		return -ENODEV;
428 
429 	if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
430 		dev_err(&PIIX4_dev->dev, "Auxiliary SMBus region 0x%x "
431 			"already in use!\n", piix4_smba);
432 		return -EBUSY;
433 	}
434 
435 	dev_info(&PIIX4_dev->dev,
436 		 "Auxiliary SMBus Host Controller at 0x%x\n",
437 		 piix4_smba);
438 
439 	return piix4_smba;
440 }
441 
442 static int piix4_transaction(struct i2c_adapter *piix4_adapter)
443 {
444 	struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(piix4_adapter);
445 	unsigned short piix4_smba = adapdata->smba;
446 	int temp;
447 	int result = 0;
448 	int timeout = 0;
449 
450 	dev_dbg(&piix4_adapter->dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
451 		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
452 		inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
453 		inb_p(SMBHSTDAT1));
454 
455 	/* Make sure the SMBus host is ready to start transmitting */
456 	if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
457 		dev_dbg(&piix4_adapter->dev, "SMBus busy (%02x). "
458 			"Resetting...\n", temp);
459 		outb_p(temp, SMBHSTSTS);
460 		if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
461 			dev_err(&piix4_adapter->dev, "Failed! (%02x)\n", temp);
462 			return -EBUSY;
463 		} else {
464 			dev_dbg(&piix4_adapter->dev, "Successful!\n");
465 		}
466 	}
467 
468 	/* start the transaction by setting bit 6 */
469 	outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT);
470 
471 	/* We will always wait for a fraction of a second! (See PIIX4 docs errata) */
472 	if (srvrworks_csb5_delay) /* Extra delay for SERVERWORKS_CSB5 */
473 		usleep_range(2000, 2100);
474 	else
475 		usleep_range(250, 500);
476 
477 	while ((++timeout < MAX_TIMEOUT) &&
478 	       ((temp = inb_p(SMBHSTSTS)) & 0x01))
479 		usleep_range(250, 500);
480 
481 	/* If the SMBus is still busy, we give up */
482 	if (timeout == MAX_TIMEOUT) {
483 		dev_err(&piix4_adapter->dev, "SMBus Timeout!\n");
484 		result = -ETIMEDOUT;
485 	}
486 
487 	if (temp & 0x10) {
488 		result = -EIO;
489 		dev_err(&piix4_adapter->dev, "Error: Failed bus transaction\n");
490 	}
491 
492 	if (temp & 0x08) {
493 		result = -EIO;
494 		dev_dbg(&piix4_adapter->dev, "Bus collision! SMBus may be "
495 			"locked until next hard reset. (sorry!)\n");
496 		/* Clock stops and slave is stuck in mid-transmission */
497 	}
498 
499 	if (temp & 0x04) {
500 		result = -ENXIO;
501 		dev_dbg(&piix4_adapter->dev, "Error: no response!\n");
502 	}
503 
504 	if (inb_p(SMBHSTSTS) != 0x00)
505 		outb_p(inb(SMBHSTSTS), SMBHSTSTS);
506 
507 	if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
508 		dev_err(&piix4_adapter->dev, "Failed reset at end of "
509 			"transaction (%02x)\n", temp);
510 	}
511 	dev_dbg(&piix4_adapter->dev, "Transaction (post): CNT=%02x, CMD=%02x, "
512 		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
513 		inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
514 		inb_p(SMBHSTDAT1));
515 	return result;
516 }
517 
518 /* Return negative errno on error. */
519 static s32 piix4_access(struct i2c_adapter * adap, u16 addr,
520 		 unsigned short flags, char read_write,
521 		 u8 command, int size, union i2c_smbus_data * data)
522 {
523 	struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
524 	unsigned short piix4_smba = adapdata->smba;
525 	int i, len;
526 	int status;
527 
528 	switch (size) {
529 	case I2C_SMBUS_QUICK:
530 		outb_p((addr << 1) | read_write,
531 		       SMBHSTADD);
532 		size = PIIX4_QUICK;
533 		break;
534 	case I2C_SMBUS_BYTE:
535 		outb_p((addr << 1) | read_write,
536 		       SMBHSTADD);
537 		if (read_write == I2C_SMBUS_WRITE)
538 			outb_p(command, SMBHSTCMD);
539 		size = PIIX4_BYTE;
540 		break;
541 	case I2C_SMBUS_BYTE_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->byte, SMBHSTDAT0);
547 		size = PIIX4_BYTE_DATA;
548 		break;
549 	case I2C_SMBUS_WORD_DATA:
550 		outb_p((addr << 1) | read_write,
551 		       SMBHSTADD);
552 		outb_p(command, SMBHSTCMD);
553 		if (read_write == I2C_SMBUS_WRITE) {
554 			outb_p(data->word & 0xff, SMBHSTDAT0);
555 			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
556 		}
557 		size = PIIX4_WORD_DATA;
558 		break;
559 	case I2C_SMBUS_BLOCK_DATA:
560 		outb_p((addr << 1) | read_write,
561 		       SMBHSTADD);
562 		outb_p(command, SMBHSTCMD);
563 		if (read_write == I2C_SMBUS_WRITE) {
564 			len = data->block[0];
565 			if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
566 				return -EINVAL;
567 			outb_p(len, SMBHSTDAT0);
568 			inb_p(SMBHSTCNT);	/* Reset SMBBLKDAT */
569 			for (i = 1; i <= len; i++)
570 				outb_p(data->block[i], SMBBLKDAT);
571 		}
572 		size = PIIX4_BLOCK_DATA;
573 		break;
574 	default:
575 		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
576 		return -EOPNOTSUPP;
577 	}
578 
579 	outb_p((size & 0x1C) + (ENABLE_INT9 & 1), SMBHSTCNT);
580 
581 	status = piix4_transaction(adap);
582 	if (status)
583 		return status;
584 
585 	if ((read_write == I2C_SMBUS_WRITE) || (size == PIIX4_QUICK))
586 		return 0;
587 
588 
589 	switch (size) {
590 	case PIIX4_BYTE:
591 	case PIIX4_BYTE_DATA:
592 		data->byte = inb_p(SMBHSTDAT0);
593 		break;
594 	case PIIX4_WORD_DATA:
595 		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
596 		break;
597 	case PIIX4_BLOCK_DATA:
598 		data->block[0] = inb_p(SMBHSTDAT0);
599 		if (data->block[0] == 0 || data->block[0] > I2C_SMBUS_BLOCK_MAX)
600 			return -EPROTO;
601 		inb_p(SMBHSTCNT);	/* Reset SMBBLKDAT */
602 		for (i = 1; i <= data->block[0]; i++)
603 			data->block[i] = inb_p(SMBBLKDAT);
604 		break;
605 	}
606 	return 0;
607 }
608 
609 static uint8_t piix4_imc_read(uint8_t idx)
610 {
611 	outb_p(idx, KERNCZ_IMC_IDX);
612 	return inb_p(KERNCZ_IMC_DATA);
613 }
614 
615 static void piix4_imc_write(uint8_t idx, uint8_t value)
616 {
617 	outb_p(idx, KERNCZ_IMC_IDX);
618 	outb_p(value, KERNCZ_IMC_DATA);
619 }
620 
621 static int piix4_imc_sleep(void)
622 {
623 	int timeout = MAX_TIMEOUT;
624 
625 	if (!request_muxed_region(KERNCZ_IMC_IDX, 2, "smbus_kerncz_imc"))
626 		return -EBUSY;
627 
628 	/* clear response register */
629 	piix4_imc_write(0x82, 0x00);
630 	/* request ownership flag */
631 	piix4_imc_write(0x83, 0xB4);
632 	/* kick off IMC Mailbox command 96 */
633 	piix4_imc_write(0x80, 0x96);
634 
635 	while (timeout--) {
636 		if (piix4_imc_read(0x82) == 0xfa) {
637 			release_region(KERNCZ_IMC_IDX, 2);
638 			return 0;
639 		}
640 		usleep_range(1000, 2000);
641 	}
642 
643 	release_region(KERNCZ_IMC_IDX, 2);
644 	return -ETIMEDOUT;
645 }
646 
647 static void piix4_imc_wakeup(void)
648 {
649 	int timeout = MAX_TIMEOUT;
650 
651 	if (!request_muxed_region(KERNCZ_IMC_IDX, 2, "smbus_kerncz_imc"))
652 		return;
653 
654 	/* clear response register */
655 	piix4_imc_write(0x82, 0x00);
656 	/* release ownership flag */
657 	piix4_imc_write(0x83, 0xB5);
658 	/* kick off IMC Mailbox command 96 */
659 	piix4_imc_write(0x80, 0x96);
660 
661 	while (timeout--) {
662 		if (piix4_imc_read(0x82) == 0xfa)
663 			break;
664 		usleep_range(1000, 2000);
665 	}
666 
667 	release_region(KERNCZ_IMC_IDX, 2);
668 }
669 
670 /*
671  * Handles access to multiple SMBus ports on the SB800.
672  * The port is selected by bits 2:1 of the smb_en register (0x2c).
673  * Returns negative errno on error.
674  *
675  * Note: The selected port must be returned to the initial selection to avoid
676  * problems on certain systems.
677  */
678 static s32 piix4_access_sb800(struct i2c_adapter *adap, u16 addr,
679 		 unsigned short flags, char read_write,
680 		 u8 command, int size, union i2c_smbus_data *data)
681 {
682 	struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
683 	unsigned short piix4_smba = adapdata->smba;
684 	int retries = MAX_TIMEOUT;
685 	int smbslvcnt;
686 	u8 smba_en_lo;
687 	u8 port;
688 	int retval;
689 
690 	if (!request_muxed_region(SB800_PIIX4_SMB_IDX, 2, "sb800_piix4_smb"))
691 		return -EBUSY;
692 
693 	/* Request the SMBUS semaphore, avoid conflicts with the IMC */
694 	smbslvcnt  = inb_p(SMBSLVCNT);
695 	do {
696 		outb_p(smbslvcnt | 0x10, SMBSLVCNT);
697 
698 		/* Check the semaphore status */
699 		smbslvcnt  = inb_p(SMBSLVCNT);
700 		if (smbslvcnt & 0x10)
701 			break;
702 
703 		usleep_range(1000, 2000);
704 	} while (--retries);
705 	/* SMBus is still owned by the IMC, we give up */
706 	if (!retries) {
707 		retval = -EBUSY;
708 		goto release;
709 	}
710 
711 	/*
712 	 * Notify the IMC (Integrated Micro Controller) if required.
713 	 * Among other responsibilities, the IMC is in charge of monitoring
714 	 * the System fans and temperature sensors, and act accordingly.
715 	 * All this is done through SMBus and can/will collide
716 	 * with our transactions if they are long (BLOCK_DATA).
717 	 * Therefore we need to request the ownership flag during those
718 	 * transactions.
719 	 */
720 	if ((size == I2C_SMBUS_BLOCK_DATA) && adapdata->notify_imc) {
721 		int ret;
722 
723 		ret = piix4_imc_sleep();
724 		switch (ret) {
725 		case -EBUSY:
726 			dev_warn(&adap->dev,
727 				 "IMC base address index region 0x%x already in use.\n",
728 				 KERNCZ_IMC_IDX);
729 			break;
730 		case -ETIMEDOUT:
731 			dev_warn(&adap->dev,
732 				 "Failed to communicate with the IMC.\n");
733 			break;
734 		default:
735 			break;
736 		}
737 
738 		/* If IMC communication fails do not retry */
739 		if (ret) {
740 			dev_warn(&adap->dev,
741 				 "Continuing without IMC notification.\n");
742 			adapdata->notify_imc = false;
743 		}
744 	}
745 
746 	outb_p(piix4_port_sel_sb800, SB800_PIIX4_SMB_IDX);
747 	smba_en_lo = inb_p(SB800_PIIX4_SMB_IDX + 1);
748 
749 	port = adapdata->port;
750 	if ((smba_en_lo & piix4_port_mask_sb800) != port)
751 		outb_p((smba_en_lo & ~piix4_port_mask_sb800) | port,
752 		       SB800_PIIX4_SMB_IDX + 1);
753 
754 	retval = piix4_access(adap, addr, flags, read_write,
755 			      command, size, data);
756 
757 	outb_p(smba_en_lo, SB800_PIIX4_SMB_IDX + 1);
758 
759 	/* Release the semaphore */
760 	outb_p(smbslvcnt | 0x20, SMBSLVCNT);
761 
762 	if ((size == I2C_SMBUS_BLOCK_DATA) && adapdata->notify_imc)
763 		piix4_imc_wakeup();
764 
765 release:
766 	release_region(SB800_PIIX4_SMB_IDX, 2);
767 	return retval;
768 }
769 
770 static u32 piix4_func(struct i2c_adapter *adapter)
771 {
772 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
773 	    I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
774 	    I2C_FUNC_SMBUS_BLOCK_DATA;
775 }
776 
777 static const struct i2c_algorithm smbus_algorithm = {
778 	.smbus_xfer	= piix4_access,
779 	.functionality	= piix4_func,
780 };
781 
782 static const struct i2c_algorithm piix4_smbus_algorithm_sb800 = {
783 	.smbus_xfer	= piix4_access_sb800,
784 	.functionality	= piix4_func,
785 };
786 
787 static const struct pci_device_id piix4_ids[] = {
788 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3) },
789 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443MX_3) },
790 	{ PCI_DEVICE(PCI_VENDOR_ID_EFAR, PCI_DEVICE_ID_EFAR_SLC90E66_3) },
791 	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP200_SMBUS) },
792 	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP300_SMBUS) },
793 	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS) },
794 	{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS) },
795 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_HUDSON2_SMBUS) },
796 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) },
797 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
798 		     PCI_DEVICE_ID_SERVERWORKS_OSB4) },
799 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
800 		     PCI_DEVICE_ID_SERVERWORKS_CSB5) },
801 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
802 		     PCI_DEVICE_ID_SERVERWORKS_CSB6) },
803 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
804 		     PCI_DEVICE_ID_SERVERWORKS_HT1000SB) },
805 	{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS,
806 		     PCI_DEVICE_ID_SERVERWORKS_HT1100LD) },
807 	{ 0, }
808 };
809 
810 MODULE_DEVICE_TABLE (pci, piix4_ids);
811 
812 static struct i2c_adapter *piix4_main_adapters[PIIX4_MAX_ADAPTERS];
813 static struct i2c_adapter *piix4_aux_adapter;
814 
815 static int piix4_add_adapter(struct pci_dev *dev, unsigned short smba,
816 			     bool sb800_main, u8 port, bool notify_imc,
817 			     const char *name, struct i2c_adapter **padap)
818 {
819 	struct i2c_adapter *adap;
820 	struct i2c_piix4_adapdata *adapdata;
821 	int retval;
822 
823 	adap = kzalloc(sizeof(*adap), GFP_KERNEL);
824 	if (adap == NULL) {
825 		release_region(smba, SMBIOSIZE);
826 		return -ENOMEM;
827 	}
828 
829 	adap->owner = THIS_MODULE;
830 	adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
831 	adap->algo = sb800_main ? &piix4_smbus_algorithm_sb800
832 				: &smbus_algorithm;
833 
834 	adapdata = kzalloc(sizeof(*adapdata), GFP_KERNEL);
835 	if (adapdata == NULL) {
836 		kfree(adap);
837 		release_region(smba, SMBIOSIZE);
838 		return -ENOMEM;
839 	}
840 
841 	adapdata->smba = smba;
842 	adapdata->sb800_main = sb800_main;
843 	adapdata->port = port << piix4_port_shift_sb800;
844 	adapdata->notify_imc = notify_imc;
845 
846 	/* set up the sysfs linkage to our parent device */
847 	adap->dev.parent = &dev->dev;
848 
849 	snprintf(adap->name, sizeof(adap->name),
850 		"SMBus PIIX4 adapter%s at %04x", name, smba);
851 
852 	i2c_set_adapdata(adap, adapdata);
853 
854 	retval = i2c_add_adapter(adap);
855 	if (retval) {
856 		kfree(adapdata);
857 		kfree(adap);
858 		release_region(smba, SMBIOSIZE);
859 		return retval;
860 	}
861 
862 	*padap = adap;
863 	return 0;
864 }
865 
866 static int piix4_add_adapters_sb800(struct pci_dev *dev, unsigned short smba,
867 				    bool notify_imc)
868 {
869 	struct i2c_piix4_adapdata *adapdata;
870 	int port;
871 	int retval;
872 
873 	for (port = 0; port < PIIX4_MAX_ADAPTERS; port++) {
874 		retval = piix4_add_adapter(dev, smba, true, port, notify_imc,
875 					   piix4_main_port_names_sb800[port],
876 					   &piix4_main_adapters[port]);
877 		if (retval < 0)
878 			goto error;
879 	}
880 
881 	return retval;
882 
883 error:
884 	dev_err(&dev->dev,
885 		"Error setting up SB800 adapters. Unregistering!\n");
886 	while (--port >= 0) {
887 		adapdata = i2c_get_adapdata(piix4_main_adapters[port]);
888 		if (adapdata->smba) {
889 			i2c_del_adapter(piix4_main_adapters[port]);
890 			kfree(adapdata);
891 			kfree(piix4_main_adapters[port]);
892 			piix4_main_adapters[port] = NULL;
893 		}
894 	}
895 
896 	return retval;
897 }
898 
899 static int piix4_probe(struct pci_dev *dev, const struct pci_device_id *id)
900 {
901 	int retval;
902 	bool is_sb800 = false;
903 
904 	if ((dev->vendor == PCI_VENDOR_ID_ATI &&
905 	     dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS &&
906 	     dev->revision >= 0x40) ||
907 	    dev->vendor == PCI_VENDOR_ID_AMD) {
908 		bool notify_imc = false;
909 		is_sb800 = true;
910 
911 		if (dev->vendor == PCI_VENDOR_ID_AMD &&
912 		    dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS) {
913 			u8 imc;
914 
915 			/*
916 			 * Detect if IMC is active or not, this method is
917 			 * described on coreboot's AMD IMC notes
918 			 */
919 			pci_bus_read_config_byte(dev->bus, PCI_DEVFN(0x14, 3),
920 						 0x40, &imc);
921 			if (imc & 0x80)
922 				notify_imc = true;
923 		}
924 
925 		/* base address location etc changed in SB800 */
926 		retval = piix4_setup_sb800(dev, id, 0);
927 		if (retval < 0)
928 			return retval;
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 			return retval;
937 	} else {
938 		retval = piix4_setup(dev, id);
939 		if (retval < 0)
940 			return retval;
941 
942 		/* Try to register main SMBus adapter, give up if we can't */
943 		retval = piix4_add_adapter(dev, retval, false, 0, false, "",
944 					   &piix4_main_adapters[0]);
945 		if (retval < 0)
946 			return retval;
947 	}
948 
949 	/* Check for auxiliary SMBus on some AMD chipsets */
950 	retval = -ENODEV;
951 
952 	if (dev->vendor == PCI_VENDOR_ID_ATI &&
953 	    dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS) {
954 		if (dev->revision < 0x40) {
955 			retval = piix4_setup_aux(dev, id, 0x58);
956 		} else {
957 			/* SB800 added aux bus too */
958 			retval = piix4_setup_sb800(dev, id, 1);
959 		}
960 	}
961 
962 	if (dev->vendor == PCI_VENDOR_ID_AMD &&
963 	    dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS) {
964 		retval = piix4_setup_sb800(dev, id, 1);
965 	}
966 
967 	if (retval > 0) {
968 		/* Try to add the aux adapter if it exists,
969 		 * piix4_add_adapter will clean up if this fails */
970 		piix4_add_adapter(dev, retval, false, 0, false,
971 				  is_sb800 ? piix4_aux_port_name_sb800 : "",
972 				  &piix4_aux_adapter);
973 	}
974 
975 	return 0;
976 }
977 
978 static void piix4_adap_remove(struct i2c_adapter *adap)
979 {
980 	struct i2c_piix4_adapdata *adapdata = i2c_get_adapdata(adap);
981 
982 	if (adapdata->smba) {
983 		i2c_del_adapter(adap);
984 		if (adapdata->port == (0 << piix4_port_shift_sb800))
985 			release_region(adapdata->smba, SMBIOSIZE);
986 		kfree(adapdata);
987 		kfree(adap);
988 	}
989 }
990 
991 static void piix4_remove(struct pci_dev *dev)
992 {
993 	int port = PIIX4_MAX_ADAPTERS;
994 
995 	while (--port >= 0) {
996 		if (piix4_main_adapters[port]) {
997 			piix4_adap_remove(piix4_main_adapters[port]);
998 			piix4_main_adapters[port] = NULL;
999 		}
1000 	}
1001 
1002 	if (piix4_aux_adapter) {
1003 		piix4_adap_remove(piix4_aux_adapter);
1004 		piix4_aux_adapter = NULL;
1005 	}
1006 }
1007 
1008 static struct pci_driver piix4_driver = {
1009 	.name		= "piix4_smbus",
1010 	.id_table	= piix4_ids,
1011 	.probe		= piix4_probe,
1012 	.remove		= piix4_remove,
1013 };
1014 
1015 module_pci_driver(piix4_driver);
1016 
1017 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
1018 		"Philip Edelbrock <phil@netroedge.com>");
1019 MODULE_DESCRIPTION("PIIX4 SMBus driver");
1020 MODULE_LICENSE("GPL");
1021