xref: /linux/drivers/pci/hotplug/shpchp_hpc.c (revision e7d759f31ca295d589f7420719c311870bb3166f)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Standard PCI Hot Plug Driver
4  *
5  * Copyright (C) 1995,2001 Compaq Computer Corporation
6  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
7  * Copyright (C) 2001 IBM Corp.
8  * Copyright (C) 2003-2004 Intel Corporation
9  *
10  * All rights reserved.
11  *
12  * Send feedback to <greg@kroah.com>,<kristen.c.accardi@intel.com>
13  *
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/types.h>
19 #include <linux/pci.h>
20 #include <linux/interrupt.h>
21 
22 #include "shpchp.h"
23 
24 /* Slot Available Register I field definition */
25 #define SLOT_33MHZ		0x0000001f
26 #define SLOT_66MHZ_PCIX		0x00001f00
27 #define SLOT_100MHZ_PCIX	0x001f0000
28 #define SLOT_133MHZ_PCIX	0x1f000000
29 
30 /* Slot Available Register II field definition */
31 #define SLOT_66MHZ		0x0000001f
32 #define SLOT_66MHZ_PCIX_266	0x00000f00
33 #define SLOT_100MHZ_PCIX_266	0x0000f000
34 #define SLOT_133MHZ_PCIX_266	0x000f0000
35 #define SLOT_66MHZ_PCIX_533	0x00f00000
36 #define SLOT_100MHZ_PCIX_533	0x0f000000
37 #define SLOT_133MHZ_PCIX_533	0xf0000000
38 
39 /* Slot Configuration */
40 #define SLOT_NUM		0x0000001F
41 #define	FIRST_DEV_NUM		0x00001F00
42 #define PSN			0x07FF0000
43 #define	UPDOWN			0x20000000
44 #define	MRLSENSOR		0x40000000
45 #define ATTN_BUTTON		0x80000000
46 
47 /*
48  * Interrupt Locator Register definitions
49  */
50 #define CMD_INTR_PENDING	(1 << 0)
51 #define SLOT_INTR_PENDING(i)	(1 << (i + 1))
52 
53 /*
54  * Controller SERR-INT Register
55  */
56 #define GLOBAL_INTR_MASK	(1 << 0)
57 #define GLOBAL_SERR_MASK	(1 << 1)
58 #define COMMAND_INTR_MASK	(1 << 2)
59 #define ARBITER_SERR_MASK	(1 << 3)
60 #define COMMAND_DETECTED	(1 << 16)
61 #define ARBITER_DETECTED	(1 << 17)
62 #define SERR_INTR_RSVDZ_MASK	0xfffc0000
63 
64 /*
65  * Logical Slot Register definitions
66  */
67 #define SLOT_REG(i)		(SLOT1 + (4 * i))
68 
69 #define SLOT_STATE_SHIFT	(0)
70 #define SLOT_STATE_MASK		(3 << 0)
71 #define SLOT_STATE_PWRONLY	(1)
72 #define SLOT_STATE_ENABLED	(2)
73 #define SLOT_STATE_DISABLED	(3)
74 #define PWR_LED_STATE_SHIFT	(2)
75 #define PWR_LED_STATE_MASK	(3 << 2)
76 #define ATN_LED_STATE_SHIFT	(4)
77 #define ATN_LED_STATE_MASK	(3 << 4)
78 #define ATN_LED_STATE_ON	(1)
79 #define ATN_LED_STATE_BLINK	(2)
80 #define ATN_LED_STATE_OFF	(3)
81 #define POWER_FAULT		(1 << 6)
82 #define ATN_BUTTON		(1 << 7)
83 #define MRL_SENSOR		(1 << 8)
84 #define MHZ66_CAP		(1 << 9)
85 #define PRSNT_SHIFT		(10)
86 #define PRSNT_MASK		(3 << 10)
87 #define PCIX_CAP_SHIFT		(12)
88 #define PCIX_CAP_MASK_PI1	(3 << 12)
89 #define PCIX_CAP_MASK_PI2	(7 << 12)
90 #define PRSNT_CHANGE_DETECTED	(1 << 16)
91 #define ISO_PFAULT_DETECTED	(1 << 17)
92 #define BUTTON_PRESS_DETECTED	(1 << 18)
93 #define MRL_CHANGE_DETECTED	(1 << 19)
94 #define CON_PFAULT_DETECTED	(1 << 20)
95 #define PRSNT_CHANGE_INTR_MASK	(1 << 24)
96 #define ISO_PFAULT_INTR_MASK	(1 << 25)
97 #define BUTTON_PRESS_INTR_MASK	(1 << 26)
98 #define MRL_CHANGE_INTR_MASK	(1 << 27)
99 #define CON_PFAULT_INTR_MASK	(1 << 28)
100 #define MRL_CHANGE_SERR_MASK	(1 << 29)
101 #define CON_PFAULT_SERR_MASK	(1 << 30)
102 #define SLOT_REG_RSVDZ_MASK	((1 << 15) | (7 << 21))
103 
104 /*
105  * SHPC Command Code definitions
106  *
107  *     Slot Operation				00h - 3Fh
108  *     Set Bus Segment Speed/Mode A		40h - 47h
109  *     Power-Only All Slots			48h
110  *     Enable All Slots				49h
111  *     Set Bus Segment Speed/Mode B (PI=2)	50h - 5Fh
112  *     Reserved Command Codes			60h - BFh
113  *     Vendor Specific Commands			C0h - FFh
114  */
115 #define SET_SLOT_PWR		0x01	/* Slot Operation */
116 #define SET_SLOT_ENABLE		0x02
117 #define SET_SLOT_DISABLE	0x03
118 #define SET_PWR_ON		0x04
119 #define SET_PWR_BLINK		0x08
120 #define SET_PWR_OFF		0x0c
121 #define SET_ATTN_ON		0x10
122 #define SET_ATTN_BLINK		0x20
123 #define SET_ATTN_OFF		0x30
124 #define SETA_PCI_33MHZ		0x40	/* Set Bus Segment Speed/Mode A */
125 #define SETA_PCI_66MHZ		0x41
126 #define SETA_PCIX_66MHZ		0x42
127 #define SETA_PCIX_100MHZ	0x43
128 #define SETA_PCIX_133MHZ	0x44
129 #define SETA_RESERVED1		0x45
130 #define SETA_RESERVED2		0x46
131 #define SETA_RESERVED3		0x47
132 #define SET_PWR_ONLY_ALL	0x48	/* Power-Only All Slots */
133 #define SET_ENABLE_ALL		0x49	/* Enable All Slots */
134 #define	SETB_PCI_33MHZ		0x50	/* Set Bus Segment Speed/Mode B */
135 #define SETB_PCI_66MHZ		0x51
136 #define SETB_PCIX_66MHZ_PM	0x52
137 #define SETB_PCIX_100MHZ_PM	0x53
138 #define SETB_PCIX_133MHZ_PM	0x54
139 #define SETB_PCIX_66MHZ_EM	0x55
140 #define SETB_PCIX_100MHZ_EM	0x56
141 #define SETB_PCIX_133MHZ_EM	0x57
142 #define SETB_PCIX_66MHZ_266	0x58
143 #define SETB_PCIX_100MHZ_266	0x59
144 #define SETB_PCIX_133MHZ_266	0x5a
145 #define SETB_PCIX_66MHZ_533	0x5b
146 #define SETB_PCIX_100MHZ_533	0x5c
147 #define SETB_PCIX_133MHZ_533	0x5d
148 #define SETB_RESERVED1		0x5e
149 #define SETB_RESERVED2		0x5f
150 
151 /*
152  * SHPC controller command error code
153  */
154 #define SWITCH_OPEN		0x1
155 #define INVALID_CMD		0x2
156 #define INVALID_SPEED_MODE	0x4
157 
158 /*
159  * For accessing SHPC Working Register Set via PCI Configuration Space
160  */
161 #define DWORD_SELECT		0x2
162 #define DWORD_DATA		0x4
163 
164 /* Field Offset in Logical Slot Register - byte boundary */
165 #define SLOT_EVENT_LATCH	0x2
166 #define SLOT_SERR_INT_MASK	0x3
167 
168 static irqreturn_t shpc_isr(int irq, void *dev_id);
169 static void start_int_poll_timer(struct controller *ctrl, int sec);
170 static int hpc_check_cmd_status(struct controller *ctrl);
171 
172 static inline u8 shpc_readb(struct controller *ctrl, int reg)
173 {
174 	return readb(ctrl->creg + reg);
175 }
176 
177 static inline u16 shpc_readw(struct controller *ctrl, int reg)
178 {
179 	return readw(ctrl->creg + reg);
180 }
181 
182 static inline void shpc_writew(struct controller *ctrl, int reg, u16 val)
183 {
184 	writew(val, ctrl->creg + reg);
185 }
186 
187 static inline u32 shpc_readl(struct controller *ctrl, int reg)
188 {
189 	return readl(ctrl->creg + reg);
190 }
191 
192 static inline void shpc_writel(struct controller *ctrl, int reg, u32 val)
193 {
194 	writel(val, ctrl->creg + reg);
195 }
196 
197 static inline int shpc_indirect_read(struct controller *ctrl, int index,
198 				     u32 *value)
199 {
200 	int rc;
201 	u32 cap_offset = ctrl->cap_offset;
202 	struct pci_dev *pdev = ctrl->pci_dev;
203 
204 	rc = pci_write_config_byte(pdev, cap_offset + DWORD_SELECT, index);
205 	if (rc)
206 		return rc;
207 	return pci_read_config_dword(pdev, cap_offset + DWORD_DATA, value);
208 }
209 
210 /*
211  * This is the interrupt polling timeout function.
212  */
213 static void int_poll_timeout(struct timer_list *t)
214 {
215 	struct controller *ctrl = from_timer(ctrl, t, poll_timer);
216 
217 	/* Poll for interrupt events.  regs == NULL => polling */
218 	shpc_isr(0, ctrl);
219 
220 	if (!shpchp_poll_time)
221 		shpchp_poll_time = 2; /* default polling interval is 2 sec */
222 
223 	start_int_poll_timer(ctrl, shpchp_poll_time);
224 }
225 
226 /*
227  * This function starts the interrupt polling timer.
228  */
229 static void start_int_poll_timer(struct controller *ctrl, int sec)
230 {
231 	/* Clamp to sane value */
232 	if ((sec <= 0) || (sec > 60))
233 		sec = 2;
234 
235 	ctrl->poll_timer.expires = jiffies + sec * HZ;
236 	add_timer(&ctrl->poll_timer);
237 }
238 
239 static inline int is_ctrl_busy(struct controller *ctrl)
240 {
241 	u16 cmd_status = shpc_readw(ctrl, CMD_STATUS);
242 	return cmd_status & 0x1;
243 }
244 
245 /*
246  * Returns 1 if SHPC finishes executing a command within 1 sec,
247  * otherwise returns 0.
248  */
249 static inline int shpc_poll_ctrl_busy(struct controller *ctrl)
250 {
251 	int i;
252 
253 	if (!is_ctrl_busy(ctrl))
254 		return 1;
255 
256 	/* Check every 0.1 sec for a total of 1 sec */
257 	for (i = 0; i < 10; i++) {
258 		msleep(100);
259 		if (!is_ctrl_busy(ctrl))
260 			return 1;
261 	}
262 
263 	return 0;
264 }
265 
266 static inline int shpc_wait_cmd(struct controller *ctrl)
267 {
268 	int retval = 0;
269 	unsigned long timeout = msecs_to_jiffies(1000);
270 	int rc;
271 
272 	if (shpchp_poll_mode)
273 		rc = shpc_poll_ctrl_busy(ctrl);
274 	else
275 		rc = wait_event_interruptible_timeout(ctrl->queue,
276 						!is_ctrl_busy(ctrl), timeout);
277 	if (!rc && is_ctrl_busy(ctrl)) {
278 		retval = -EIO;
279 		ctrl_err(ctrl, "Command not completed in 1000 msec\n");
280 	} else if (rc < 0) {
281 		retval = -EINTR;
282 		ctrl_info(ctrl, "Command was interrupted by a signal\n");
283 	}
284 
285 	return retval;
286 }
287 
288 static int shpc_write_cmd(struct slot *slot, u8 t_slot, u8 cmd)
289 {
290 	struct controller *ctrl = slot->ctrl;
291 	u16 cmd_status;
292 	int retval = 0;
293 	u16 temp_word;
294 
295 	mutex_lock(&slot->ctrl->cmd_lock);
296 
297 	if (!shpc_poll_ctrl_busy(ctrl)) {
298 		/* After 1 sec and the controller is still busy */
299 		ctrl_err(ctrl, "Controller is still busy after 1 sec\n");
300 		retval = -EBUSY;
301 		goto out;
302 	}
303 
304 	++t_slot;
305 	temp_word =  (t_slot << 8) | (cmd & 0xFF);
306 	ctrl_dbg(ctrl, "%s: t_slot %x cmd %x\n", __func__, t_slot, cmd);
307 
308 	/* To make sure the Controller Busy bit is 0 before we send out the
309 	 * command.
310 	 */
311 	shpc_writew(ctrl, CMD, temp_word);
312 
313 	/*
314 	 * Wait for command completion.
315 	 */
316 	retval = shpc_wait_cmd(slot->ctrl);
317 	if (retval)
318 		goto out;
319 
320 	cmd_status = hpc_check_cmd_status(slot->ctrl);
321 	if (cmd_status) {
322 		ctrl_err(ctrl, "Failed to issued command 0x%x (error code = %d)\n",
323 			 cmd, cmd_status);
324 		retval = -EIO;
325 	}
326  out:
327 	mutex_unlock(&slot->ctrl->cmd_lock);
328 	return retval;
329 }
330 
331 static int hpc_check_cmd_status(struct controller *ctrl)
332 {
333 	int retval = 0;
334 	u16 cmd_status = shpc_readw(ctrl, CMD_STATUS) & 0x000F;
335 
336 	switch (cmd_status >> 1) {
337 	case 0:
338 		retval = 0;
339 		break;
340 	case 1:
341 		retval = SWITCH_OPEN;
342 		ctrl_err(ctrl, "Switch opened!\n");
343 		break;
344 	case 2:
345 		retval = INVALID_CMD;
346 		ctrl_err(ctrl, "Invalid HPC command!\n");
347 		break;
348 	case 4:
349 		retval = INVALID_SPEED_MODE;
350 		ctrl_err(ctrl, "Invalid bus speed/mode!\n");
351 		break;
352 	default:
353 		retval = cmd_status;
354 	}
355 
356 	return retval;
357 }
358 
359 
360 static int hpc_get_attention_status(struct slot *slot, u8 *status)
361 {
362 	struct controller *ctrl = slot->ctrl;
363 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
364 	u8 state = (slot_reg & ATN_LED_STATE_MASK) >> ATN_LED_STATE_SHIFT;
365 
366 	switch (state) {
367 	case ATN_LED_STATE_ON:
368 		*status = 1;	/* On */
369 		break;
370 	case ATN_LED_STATE_BLINK:
371 		*status = 2;	/* Blink */
372 		break;
373 	case ATN_LED_STATE_OFF:
374 		*status = 0;	/* Off */
375 		break;
376 	default:
377 		*status = 0xFF;	/* Reserved */
378 		break;
379 	}
380 
381 	return 0;
382 }
383 
384 static int hpc_get_power_status(struct slot *slot, u8 *status)
385 {
386 	struct controller *ctrl = slot->ctrl;
387 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
388 	u8 state = (slot_reg & SLOT_STATE_MASK) >> SLOT_STATE_SHIFT;
389 
390 	switch (state) {
391 	case SLOT_STATE_PWRONLY:
392 		*status = 2;	/* Powered only */
393 		break;
394 	case SLOT_STATE_ENABLED:
395 		*status = 1;	/* Enabled */
396 		break;
397 	case SLOT_STATE_DISABLED:
398 		*status = 0;	/* Disabled */
399 		break;
400 	default:
401 		*status = 0xFF;	/* Reserved */
402 		break;
403 	}
404 
405 	return 0;
406 }
407 
408 
409 static int hpc_get_latch_status(struct slot *slot, u8 *status)
410 {
411 	struct controller *ctrl = slot->ctrl;
412 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
413 
414 	*status = !!(slot_reg & MRL_SENSOR);	/* 0 -> close; 1 -> open */
415 
416 	return 0;
417 }
418 
419 static int hpc_get_adapter_status(struct slot *slot, u8 *status)
420 {
421 	struct controller *ctrl = slot->ctrl;
422 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
423 	u8 state = (slot_reg & PRSNT_MASK) >> PRSNT_SHIFT;
424 
425 	*status = (state != 0x3) ? 1 : 0;
426 
427 	return 0;
428 }
429 
430 static int hpc_get_prog_int(struct slot *slot, u8 *prog_int)
431 {
432 	struct controller *ctrl = slot->ctrl;
433 
434 	*prog_int = shpc_readb(ctrl, PROG_INTERFACE);
435 
436 	return 0;
437 }
438 
439 static int hpc_get_adapter_speed(struct slot *slot, enum pci_bus_speed *value)
440 {
441 	int retval = 0;
442 	struct controller *ctrl = slot->ctrl;
443 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
444 	u8 m66_cap  = !!(slot_reg & MHZ66_CAP);
445 	u8 pi, pcix_cap;
446 
447 	retval = hpc_get_prog_int(slot, &pi);
448 	if (retval)
449 		return retval;
450 
451 	switch (pi) {
452 	case 1:
453 		pcix_cap = (slot_reg & PCIX_CAP_MASK_PI1) >> PCIX_CAP_SHIFT;
454 		break;
455 	case 2:
456 		pcix_cap = (slot_reg & PCIX_CAP_MASK_PI2) >> PCIX_CAP_SHIFT;
457 		break;
458 	default:
459 		return -ENODEV;
460 	}
461 
462 	ctrl_dbg(ctrl, "%s: slot_reg = %x, pcix_cap = %x, m66_cap = %x\n",
463 		 __func__, slot_reg, pcix_cap, m66_cap);
464 
465 	switch (pcix_cap) {
466 	case 0x0:
467 		*value = m66_cap ? PCI_SPEED_66MHz : PCI_SPEED_33MHz;
468 		break;
469 	case 0x1:
470 		*value = PCI_SPEED_66MHz_PCIX;
471 		break;
472 	case 0x3:
473 		*value = PCI_SPEED_133MHz_PCIX;
474 		break;
475 	case 0x4:
476 		*value = PCI_SPEED_133MHz_PCIX_266;
477 		break;
478 	case 0x5:
479 		*value = PCI_SPEED_133MHz_PCIX_533;
480 		break;
481 	case 0x2:
482 	default:
483 		*value = PCI_SPEED_UNKNOWN;
484 		retval = -ENODEV;
485 		break;
486 	}
487 
488 	ctrl_dbg(ctrl, "Adapter speed = %d\n", *value);
489 	return retval;
490 }
491 
492 static int hpc_query_power_fault(struct slot *slot)
493 {
494 	struct controller *ctrl = slot->ctrl;
495 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
496 
497 	/* Note: Logic 0 => fault */
498 	return !(slot_reg & POWER_FAULT);
499 }
500 
501 static int hpc_set_attention_status(struct slot *slot, u8 value)
502 {
503 	u8 slot_cmd = 0;
504 
505 	switch (value) {
506 		case 0:
507 			slot_cmd = SET_ATTN_OFF;	/* OFF */
508 			break;
509 		case 1:
510 			slot_cmd = SET_ATTN_ON;		/* ON */
511 			break;
512 		case 2:
513 			slot_cmd = SET_ATTN_BLINK;	/* BLINK */
514 			break;
515 		default:
516 			return -1;
517 	}
518 
519 	return shpc_write_cmd(slot, slot->hp_slot, slot_cmd);
520 }
521 
522 
523 static void hpc_set_green_led_on(struct slot *slot)
524 {
525 	shpc_write_cmd(slot, slot->hp_slot, SET_PWR_ON);
526 }
527 
528 static void hpc_set_green_led_off(struct slot *slot)
529 {
530 	shpc_write_cmd(slot, slot->hp_slot, SET_PWR_OFF);
531 }
532 
533 static void hpc_set_green_led_blink(struct slot *slot)
534 {
535 	shpc_write_cmd(slot, slot->hp_slot, SET_PWR_BLINK);
536 }
537 
538 static void hpc_release_ctlr(struct controller *ctrl)
539 {
540 	int i;
541 	u32 slot_reg, serr_int;
542 
543 	/*
544 	 * Mask event interrupts and SERRs of all slots
545 	 */
546 	for (i = 0; i < ctrl->num_slots; i++) {
547 		slot_reg = shpc_readl(ctrl, SLOT_REG(i));
548 		slot_reg |= (PRSNT_CHANGE_INTR_MASK | ISO_PFAULT_INTR_MASK |
549 			     BUTTON_PRESS_INTR_MASK | MRL_CHANGE_INTR_MASK |
550 			     CON_PFAULT_INTR_MASK   | MRL_CHANGE_SERR_MASK |
551 			     CON_PFAULT_SERR_MASK);
552 		slot_reg &= ~SLOT_REG_RSVDZ_MASK;
553 		shpc_writel(ctrl, SLOT_REG(i), slot_reg);
554 	}
555 
556 	cleanup_slots(ctrl);
557 
558 	/*
559 	 * Mask SERR and System Interrupt generation
560 	 */
561 	serr_int = shpc_readl(ctrl, SERR_INTR_ENABLE);
562 	serr_int |= (GLOBAL_INTR_MASK  | GLOBAL_SERR_MASK |
563 		     COMMAND_INTR_MASK | ARBITER_SERR_MASK);
564 	serr_int &= ~SERR_INTR_RSVDZ_MASK;
565 	shpc_writel(ctrl, SERR_INTR_ENABLE, serr_int);
566 
567 	if (shpchp_poll_mode)
568 		del_timer(&ctrl->poll_timer);
569 	else {
570 		free_irq(ctrl->pci_dev->irq, ctrl);
571 		pci_disable_msi(ctrl->pci_dev);
572 	}
573 
574 	iounmap(ctrl->creg);
575 	release_mem_region(ctrl->mmio_base, ctrl->mmio_size);
576 }
577 
578 static int hpc_power_on_slot(struct slot *slot)
579 {
580 	int retval;
581 
582 	retval = shpc_write_cmd(slot, slot->hp_slot, SET_SLOT_PWR);
583 	if (retval)
584 		ctrl_err(slot->ctrl, "%s: Write command failed!\n", __func__);
585 
586 	return retval;
587 }
588 
589 static int hpc_slot_enable(struct slot *slot)
590 {
591 	int retval;
592 
593 	/* Slot - Enable, Power Indicator - Blink, Attention Indicator - Off */
594 	retval = shpc_write_cmd(slot, slot->hp_slot,
595 			SET_SLOT_ENABLE | SET_PWR_BLINK | SET_ATTN_OFF);
596 	if (retval)
597 		ctrl_err(slot->ctrl, "%s: Write command failed!\n", __func__);
598 
599 	return retval;
600 }
601 
602 static int hpc_slot_disable(struct slot *slot)
603 {
604 	int retval;
605 
606 	/* Slot - Disable, Power Indicator - Off, Attention Indicator - On */
607 	retval = shpc_write_cmd(slot, slot->hp_slot,
608 			SET_SLOT_DISABLE | SET_PWR_OFF | SET_ATTN_ON);
609 	if (retval)
610 		ctrl_err(slot->ctrl, "%s: Write command failed!\n", __func__);
611 
612 	return retval;
613 }
614 
615 static int shpc_get_cur_bus_speed(struct controller *ctrl)
616 {
617 	int retval = 0;
618 	struct pci_bus *bus = ctrl->pci_dev->subordinate;
619 	enum pci_bus_speed bus_speed = PCI_SPEED_UNKNOWN;
620 	u16 sec_bus_reg = shpc_readw(ctrl, SEC_BUS_CONFIG);
621 	u8 pi = shpc_readb(ctrl, PROG_INTERFACE);
622 	u8 speed_mode = (pi == 2) ? (sec_bus_reg & 0xF) : (sec_bus_reg & 0x7);
623 
624 	if ((pi == 1) && (speed_mode > 4)) {
625 		retval = -ENODEV;
626 		goto out;
627 	}
628 
629 	switch (speed_mode) {
630 	case 0x0:
631 		bus_speed = PCI_SPEED_33MHz;
632 		break;
633 	case 0x1:
634 		bus_speed = PCI_SPEED_66MHz;
635 		break;
636 	case 0x2:
637 		bus_speed = PCI_SPEED_66MHz_PCIX;
638 		break;
639 	case 0x3:
640 		bus_speed = PCI_SPEED_100MHz_PCIX;
641 		break;
642 	case 0x4:
643 		bus_speed = PCI_SPEED_133MHz_PCIX;
644 		break;
645 	case 0x5:
646 		bus_speed = PCI_SPEED_66MHz_PCIX_ECC;
647 		break;
648 	case 0x6:
649 		bus_speed = PCI_SPEED_100MHz_PCIX_ECC;
650 		break;
651 	case 0x7:
652 		bus_speed = PCI_SPEED_133MHz_PCIX_ECC;
653 		break;
654 	case 0x8:
655 		bus_speed = PCI_SPEED_66MHz_PCIX_266;
656 		break;
657 	case 0x9:
658 		bus_speed = PCI_SPEED_100MHz_PCIX_266;
659 		break;
660 	case 0xa:
661 		bus_speed = PCI_SPEED_133MHz_PCIX_266;
662 		break;
663 	case 0xb:
664 		bus_speed = PCI_SPEED_66MHz_PCIX_533;
665 		break;
666 	case 0xc:
667 		bus_speed = PCI_SPEED_100MHz_PCIX_533;
668 		break;
669 	case 0xd:
670 		bus_speed = PCI_SPEED_133MHz_PCIX_533;
671 		break;
672 	default:
673 		retval = -ENODEV;
674 		break;
675 	}
676 
677  out:
678 	bus->cur_bus_speed = bus_speed;
679 	dbg("Current bus speed = %d\n", bus_speed);
680 	return retval;
681 }
682 
683 
684 static int hpc_set_bus_speed_mode(struct slot *slot, enum pci_bus_speed value)
685 {
686 	int retval;
687 	struct controller *ctrl = slot->ctrl;
688 	u8 pi, cmd;
689 
690 	pi = shpc_readb(ctrl, PROG_INTERFACE);
691 	if ((pi == 1) && (value > PCI_SPEED_133MHz_PCIX))
692 		return -EINVAL;
693 
694 	switch (value) {
695 	case PCI_SPEED_33MHz:
696 		cmd = SETA_PCI_33MHZ;
697 		break;
698 	case PCI_SPEED_66MHz:
699 		cmd = SETA_PCI_66MHZ;
700 		break;
701 	case PCI_SPEED_66MHz_PCIX:
702 		cmd = SETA_PCIX_66MHZ;
703 		break;
704 	case PCI_SPEED_100MHz_PCIX:
705 		cmd = SETA_PCIX_100MHZ;
706 		break;
707 	case PCI_SPEED_133MHz_PCIX:
708 		cmd = SETA_PCIX_133MHZ;
709 		break;
710 	case PCI_SPEED_66MHz_PCIX_ECC:
711 		cmd = SETB_PCIX_66MHZ_EM;
712 		break;
713 	case PCI_SPEED_100MHz_PCIX_ECC:
714 		cmd = SETB_PCIX_100MHZ_EM;
715 		break;
716 	case PCI_SPEED_133MHz_PCIX_ECC:
717 		cmd = SETB_PCIX_133MHZ_EM;
718 		break;
719 	case PCI_SPEED_66MHz_PCIX_266:
720 		cmd = SETB_PCIX_66MHZ_266;
721 		break;
722 	case PCI_SPEED_100MHz_PCIX_266:
723 		cmd = SETB_PCIX_100MHZ_266;
724 		break;
725 	case PCI_SPEED_133MHz_PCIX_266:
726 		cmd = SETB_PCIX_133MHZ_266;
727 		break;
728 	case PCI_SPEED_66MHz_PCIX_533:
729 		cmd = SETB_PCIX_66MHZ_533;
730 		break;
731 	case PCI_SPEED_100MHz_PCIX_533:
732 		cmd = SETB_PCIX_100MHZ_533;
733 		break;
734 	case PCI_SPEED_133MHz_PCIX_533:
735 		cmd = SETB_PCIX_133MHZ_533;
736 		break;
737 	default:
738 		return -EINVAL;
739 	}
740 
741 	retval = shpc_write_cmd(slot, 0, cmd);
742 	if (retval)
743 		ctrl_err(ctrl, "%s: Write command failed!\n", __func__);
744 	else
745 		shpc_get_cur_bus_speed(ctrl);
746 
747 	return retval;
748 }
749 
750 static irqreturn_t shpc_isr(int irq, void *dev_id)
751 {
752 	struct controller *ctrl = (struct controller *)dev_id;
753 	u32 serr_int, slot_reg, intr_loc, intr_loc2;
754 	int hp_slot;
755 
756 	/* Check to see if it was our interrupt */
757 	intr_loc = shpc_readl(ctrl, INTR_LOC);
758 	if (!intr_loc)
759 		return IRQ_NONE;
760 
761 	ctrl_dbg(ctrl, "%s: intr_loc = %x\n", __func__, intr_loc);
762 
763 	if (!shpchp_poll_mode) {
764 		/*
765 		 * Mask Global Interrupt Mask - see implementation
766 		 * note on p. 139 of SHPC spec rev 1.0
767 		 */
768 		serr_int = shpc_readl(ctrl, SERR_INTR_ENABLE);
769 		serr_int |= GLOBAL_INTR_MASK;
770 		serr_int &= ~SERR_INTR_RSVDZ_MASK;
771 		shpc_writel(ctrl, SERR_INTR_ENABLE, serr_int);
772 
773 		intr_loc2 = shpc_readl(ctrl, INTR_LOC);
774 		ctrl_dbg(ctrl, "%s: intr_loc2 = %x\n", __func__, intr_loc2);
775 	}
776 
777 	if (intr_loc & CMD_INTR_PENDING) {
778 		/*
779 		 * Command Complete Interrupt Pending
780 		 * RO only - clear by writing 1 to the Command Completion
781 		 * Detect bit in Controller SERR-INT register
782 		 */
783 		serr_int = shpc_readl(ctrl, SERR_INTR_ENABLE);
784 		serr_int &= ~SERR_INTR_RSVDZ_MASK;
785 		shpc_writel(ctrl, SERR_INTR_ENABLE, serr_int);
786 
787 		wake_up_interruptible(&ctrl->queue);
788 	}
789 
790 	if (!(intr_loc & ~CMD_INTR_PENDING))
791 		goto out;
792 
793 	for (hp_slot = 0; hp_slot < ctrl->num_slots; hp_slot++) {
794 		/* To find out which slot has interrupt pending */
795 		if (!(intr_loc & SLOT_INTR_PENDING(hp_slot)))
796 			continue;
797 
798 		slot_reg = shpc_readl(ctrl, SLOT_REG(hp_slot));
799 		ctrl_dbg(ctrl, "Slot %x with intr, slot register = %x\n",
800 			 hp_slot, slot_reg);
801 
802 		if (slot_reg & MRL_CHANGE_DETECTED)
803 			shpchp_handle_switch_change(hp_slot, ctrl);
804 
805 		if (slot_reg & BUTTON_PRESS_DETECTED)
806 			shpchp_handle_attention_button(hp_slot, ctrl);
807 
808 		if (slot_reg & PRSNT_CHANGE_DETECTED)
809 			shpchp_handle_presence_change(hp_slot, ctrl);
810 
811 		if (slot_reg & (ISO_PFAULT_DETECTED | CON_PFAULT_DETECTED))
812 			shpchp_handle_power_fault(hp_slot, ctrl);
813 
814 		/* Clear all slot events */
815 		slot_reg &= ~SLOT_REG_RSVDZ_MASK;
816 		shpc_writel(ctrl, SLOT_REG(hp_slot), slot_reg);
817 	}
818  out:
819 	if (!shpchp_poll_mode) {
820 		/* Unmask Global Interrupt Mask */
821 		serr_int = shpc_readl(ctrl, SERR_INTR_ENABLE);
822 		serr_int &= ~(GLOBAL_INTR_MASK | SERR_INTR_RSVDZ_MASK);
823 		shpc_writel(ctrl, SERR_INTR_ENABLE, serr_int);
824 	}
825 
826 	return IRQ_HANDLED;
827 }
828 
829 static int shpc_get_max_bus_speed(struct controller *ctrl)
830 {
831 	int retval = 0;
832 	struct pci_bus *bus = ctrl->pci_dev->subordinate;
833 	enum pci_bus_speed bus_speed = PCI_SPEED_UNKNOWN;
834 	u8 pi = shpc_readb(ctrl, PROG_INTERFACE);
835 	u32 slot_avail1 = shpc_readl(ctrl, SLOT_AVAIL1);
836 	u32 slot_avail2 = shpc_readl(ctrl, SLOT_AVAIL2);
837 
838 	if (pi == 2) {
839 		if (slot_avail2 & SLOT_133MHZ_PCIX_533)
840 			bus_speed = PCI_SPEED_133MHz_PCIX_533;
841 		else if (slot_avail2 & SLOT_100MHZ_PCIX_533)
842 			bus_speed = PCI_SPEED_100MHz_PCIX_533;
843 		else if (slot_avail2 & SLOT_66MHZ_PCIX_533)
844 			bus_speed = PCI_SPEED_66MHz_PCIX_533;
845 		else if (slot_avail2 & SLOT_133MHZ_PCIX_266)
846 			bus_speed = PCI_SPEED_133MHz_PCIX_266;
847 		else if (slot_avail2 & SLOT_100MHZ_PCIX_266)
848 			bus_speed = PCI_SPEED_100MHz_PCIX_266;
849 		else if (slot_avail2 & SLOT_66MHZ_PCIX_266)
850 			bus_speed = PCI_SPEED_66MHz_PCIX_266;
851 	}
852 
853 	if (bus_speed == PCI_SPEED_UNKNOWN) {
854 		if (slot_avail1 & SLOT_133MHZ_PCIX)
855 			bus_speed = PCI_SPEED_133MHz_PCIX;
856 		else if (slot_avail1 & SLOT_100MHZ_PCIX)
857 			bus_speed = PCI_SPEED_100MHz_PCIX;
858 		else if (slot_avail1 & SLOT_66MHZ_PCIX)
859 			bus_speed = PCI_SPEED_66MHz_PCIX;
860 		else if (slot_avail2 & SLOT_66MHZ)
861 			bus_speed = PCI_SPEED_66MHz;
862 		else if (slot_avail1 & SLOT_33MHZ)
863 			bus_speed = PCI_SPEED_33MHz;
864 		else
865 			retval = -ENODEV;
866 	}
867 
868 	bus->max_bus_speed = bus_speed;
869 	ctrl_dbg(ctrl, "Max bus speed = %d\n", bus_speed);
870 
871 	return retval;
872 }
873 
874 static const struct hpc_ops shpchp_hpc_ops = {
875 	.power_on_slot			= hpc_power_on_slot,
876 	.slot_enable			= hpc_slot_enable,
877 	.slot_disable			= hpc_slot_disable,
878 	.set_bus_speed_mode		= hpc_set_bus_speed_mode,
879 	.set_attention_status	= hpc_set_attention_status,
880 	.get_power_status		= hpc_get_power_status,
881 	.get_attention_status	= hpc_get_attention_status,
882 	.get_latch_status		= hpc_get_latch_status,
883 	.get_adapter_status		= hpc_get_adapter_status,
884 
885 	.get_adapter_speed		= hpc_get_adapter_speed,
886 	.get_prog_int			= hpc_get_prog_int,
887 
888 	.query_power_fault		= hpc_query_power_fault,
889 	.green_led_on			= hpc_set_green_led_on,
890 	.green_led_off			= hpc_set_green_led_off,
891 	.green_led_blink		= hpc_set_green_led_blink,
892 
893 	.release_ctlr			= hpc_release_ctlr,
894 };
895 
896 int shpc_init(struct controller *ctrl, struct pci_dev *pdev)
897 {
898 	int rc = -1, num_slots = 0;
899 	u8 hp_slot;
900 	u32 shpc_base_offset;
901 	u32 tempdword, slot_reg, slot_config;
902 	u8 i;
903 
904 	ctrl->pci_dev = pdev;  /* pci_dev of the P2P bridge */
905 	ctrl_dbg(ctrl, "Hotplug Controller:\n");
906 
907 	if (pdev->vendor == PCI_VENDOR_ID_AMD &&
908 	    pdev->device == PCI_DEVICE_ID_AMD_GOLAM_7450) {
909 		/* amd shpc driver doesn't use Base Offset; assume 0 */
910 		ctrl->mmio_base = pci_resource_start(pdev, 0);
911 		ctrl->mmio_size = pci_resource_len(pdev, 0);
912 	} else {
913 		ctrl->cap_offset = pci_find_capability(pdev, PCI_CAP_ID_SHPC);
914 		if (!ctrl->cap_offset) {
915 			ctrl_err(ctrl, "Cannot find PCI capability\n");
916 			goto abort;
917 		}
918 		ctrl_dbg(ctrl, " cap_offset = %x\n", ctrl->cap_offset);
919 
920 		rc = shpc_indirect_read(ctrl, 0, &shpc_base_offset);
921 		if (rc) {
922 			ctrl_err(ctrl, "Cannot read base_offset\n");
923 			goto abort;
924 		}
925 
926 		rc = shpc_indirect_read(ctrl, 3, &tempdword);
927 		if (rc) {
928 			ctrl_err(ctrl, "Cannot read slot config\n");
929 			goto abort;
930 		}
931 		num_slots = tempdword & SLOT_NUM;
932 		ctrl_dbg(ctrl, " num_slots (indirect) %x\n", num_slots);
933 
934 		for (i = 0; i < 9 + num_slots; i++) {
935 			rc = shpc_indirect_read(ctrl, i, &tempdword);
936 			if (rc) {
937 				ctrl_err(ctrl, "Cannot read creg (index = %d)\n",
938 					 i);
939 				goto abort;
940 			}
941 			ctrl_dbg(ctrl, " offset %d: value %x\n", i, tempdword);
942 		}
943 
944 		ctrl->mmio_base =
945 			pci_resource_start(pdev, 0) + shpc_base_offset;
946 		ctrl->mmio_size = 0x24 + 0x4 * num_slots;
947 	}
948 
949 	ctrl_info(ctrl, "HPC vendor_id %x device_id %x ss_vid %x ss_did %x\n",
950 		  pdev->vendor, pdev->device, pdev->subsystem_vendor,
951 		  pdev->subsystem_device);
952 
953 	rc = pci_enable_device(pdev);
954 	if (rc) {
955 		ctrl_err(ctrl, "pci_enable_device failed\n");
956 		goto abort;
957 	}
958 
959 	if (!request_mem_region(ctrl->mmio_base, ctrl->mmio_size, MY_NAME)) {
960 		ctrl_err(ctrl, "Cannot reserve MMIO region\n");
961 		rc = -1;
962 		goto abort;
963 	}
964 
965 	ctrl->creg = ioremap(ctrl->mmio_base, ctrl->mmio_size);
966 	if (!ctrl->creg) {
967 		ctrl_err(ctrl, "Cannot remap MMIO region %lx @ %lx\n",
968 			 ctrl->mmio_size, ctrl->mmio_base);
969 		release_mem_region(ctrl->mmio_base, ctrl->mmio_size);
970 		rc = -1;
971 		goto abort;
972 	}
973 	ctrl_dbg(ctrl, "ctrl->creg %p\n", ctrl->creg);
974 
975 	mutex_init(&ctrl->crit_sect);
976 	mutex_init(&ctrl->cmd_lock);
977 
978 	/* Setup wait queue */
979 	init_waitqueue_head(&ctrl->queue);
980 
981 	ctrl->hpc_ops = &shpchp_hpc_ops;
982 
983 	/* Return PCI Controller Info */
984 	slot_config = shpc_readl(ctrl, SLOT_CONFIG);
985 	ctrl->slot_device_offset = (slot_config & FIRST_DEV_NUM) >> 8;
986 	ctrl->num_slots = slot_config & SLOT_NUM;
987 	ctrl->first_slot = (slot_config & PSN) >> 16;
988 	ctrl->slot_num_inc = ((slot_config & UPDOWN) >> 29) ? 1 : -1;
989 
990 	/* Mask Global Interrupt Mask & Command Complete Interrupt Mask */
991 	tempdword = shpc_readl(ctrl, SERR_INTR_ENABLE);
992 	ctrl_dbg(ctrl, "SERR_INTR_ENABLE = %x\n", tempdword);
993 	tempdword |= (GLOBAL_INTR_MASK  | GLOBAL_SERR_MASK |
994 		      COMMAND_INTR_MASK | ARBITER_SERR_MASK);
995 	tempdword &= ~SERR_INTR_RSVDZ_MASK;
996 	shpc_writel(ctrl, SERR_INTR_ENABLE, tempdword);
997 	tempdword = shpc_readl(ctrl, SERR_INTR_ENABLE);
998 	ctrl_dbg(ctrl, "SERR_INTR_ENABLE = %x\n", tempdword);
999 
1000 	/* Mask the MRL sensor SERR Mask of individual slot in
1001 	 * Slot SERR-INT Mask & clear all the existing event if any
1002 	 */
1003 	for (hp_slot = 0; hp_slot < ctrl->num_slots; hp_slot++) {
1004 		slot_reg = shpc_readl(ctrl, SLOT_REG(hp_slot));
1005 		ctrl_dbg(ctrl, "Default Logical Slot Register %d value %x\n",
1006 			 hp_slot, slot_reg);
1007 		slot_reg |= (PRSNT_CHANGE_INTR_MASK | ISO_PFAULT_INTR_MASK |
1008 			     BUTTON_PRESS_INTR_MASK | MRL_CHANGE_INTR_MASK |
1009 			     CON_PFAULT_INTR_MASK   | MRL_CHANGE_SERR_MASK |
1010 			     CON_PFAULT_SERR_MASK);
1011 		slot_reg &= ~SLOT_REG_RSVDZ_MASK;
1012 		shpc_writel(ctrl, SLOT_REG(hp_slot), slot_reg);
1013 	}
1014 
1015 	if (shpchp_poll_mode) {
1016 		/* Install interrupt polling timer. Start with 10 sec delay */
1017 		timer_setup(&ctrl->poll_timer, int_poll_timeout, 0);
1018 		start_int_poll_timer(ctrl, 10);
1019 	} else {
1020 		/* Installs the interrupt handler */
1021 		rc = pci_enable_msi(pdev);
1022 		if (rc) {
1023 			ctrl_info(ctrl, "Can't get msi for the hotplug controller\n");
1024 			ctrl_info(ctrl, "Use INTx for the hotplug controller\n");
1025 		} else {
1026 			pci_set_master(pdev);
1027 		}
1028 
1029 		rc = request_irq(ctrl->pci_dev->irq, shpc_isr, IRQF_SHARED,
1030 				 MY_NAME, (void *)ctrl);
1031 		ctrl_dbg(ctrl, "request_irq %d (returns %d)\n",
1032 			 ctrl->pci_dev->irq, rc);
1033 		if (rc) {
1034 			ctrl_err(ctrl, "Can't get irq %d for the hotplug controller\n",
1035 				 ctrl->pci_dev->irq);
1036 			goto abort_iounmap;
1037 		}
1038 	}
1039 	ctrl_dbg(ctrl, "HPC at %s irq=%x\n", pci_name(pdev), pdev->irq);
1040 
1041 	shpc_get_max_bus_speed(ctrl);
1042 	shpc_get_cur_bus_speed(ctrl);
1043 
1044 	/*
1045 	 * Unmask all event interrupts of all slots
1046 	 */
1047 	for (hp_slot = 0; hp_slot < ctrl->num_slots; hp_slot++) {
1048 		slot_reg = shpc_readl(ctrl, SLOT_REG(hp_slot));
1049 		ctrl_dbg(ctrl, "Default Logical Slot Register %d value %x\n",
1050 			 hp_slot, slot_reg);
1051 		slot_reg &= ~(PRSNT_CHANGE_INTR_MASK | ISO_PFAULT_INTR_MASK |
1052 			      BUTTON_PRESS_INTR_MASK | MRL_CHANGE_INTR_MASK |
1053 			      CON_PFAULT_INTR_MASK | SLOT_REG_RSVDZ_MASK);
1054 		shpc_writel(ctrl, SLOT_REG(hp_slot), slot_reg);
1055 	}
1056 	if (!shpchp_poll_mode) {
1057 		/* Unmask all general input interrupts and SERR */
1058 		tempdword = shpc_readl(ctrl, SERR_INTR_ENABLE);
1059 		tempdword &= ~(GLOBAL_INTR_MASK | COMMAND_INTR_MASK |
1060 			       SERR_INTR_RSVDZ_MASK);
1061 		shpc_writel(ctrl, SERR_INTR_ENABLE, tempdword);
1062 		tempdword = shpc_readl(ctrl, SERR_INTR_ENABLE);
1063 		ctrl_dbg(ctrl, "SERR_INTR_ENABLE = %x\n", tempdword);
1064 	}
1065 
1066 	return 0;
1067 
1068 	/* We end up here for the many possible ways to fail this API.  */
1069 abort_iounmap:
1070 	iounmap(ctrl->creg);
1071 abort:
1072 	return rc;
1073 }
1074