xref: /openbmc/linux/drivers/pci/hotplug/shpchp_hpc.c (revision 206204a1)
1 /*
2  * Standard PCI Hot Plug Driver
3  *
4  * Copyright (C) 1995,2001 Compaq Computer Corporation
5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2001 IBM Corp.
7  * Copyright (C) 2003-2004 Intel Corporation
8  *
9  * All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or (at
14  * your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
19  * NON INFRINGEMENT.  See the GNU General Public License for more
20  * details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  * Send feedback to <greg@kroah.com>,<kristen.c.accardi@intel.com>
27  *
28  */
29 
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/types.h>
33 #include <linux/pci.h>
34 #include <linux/interrupt.h>
35 
36 #include "shpchp.h"
37 
38 /* Slot Available Register I field definition */
39 #define SLOT_33MHZ		0x0000001f
40 #define SLOT_66MHZ_PCIX		0x00001f00
41 #define SLOT_100MHZ_PCIX	0x001f0000
42 #define SLOT_133MHZ_PCIX	0x1f000000
43 
44 /* Slot Available Register II field definition */
45 #define SLOT_66MHZ		0x0000001f
46 #define SLOT_66MHZ_PCIX_266	0x00000f00
47 #define SLOT_100MHZ_PCIX_266	0x0000f000
48 #define SLOT_133MHZ_PCIX_266	0x000f0000
49 #define SLOT_66MHZ_PCIX_533	0x00f00000
50 #define SLOT_100MHZ_PCIX_533	0x0f000000
51 #define SLOT_133MHZ_PCIX_533	0xf0000000
52 
53 /* Slot Configuration */
54 #define SLOT_NUM		0x0000001F
55 #define	FIRST_DEV_NUM		0x00001F00
56 #define PSN			0x07FF0000
57 #define	UPDOWN			0x20000000
58 #define	MRLSENSOR		0x40000000
59 #define ATTN_BUTTON		0x80000000
60 
61 /*
62  * Interrupt Locator Register definitions
63  */
64 #define CMD_INTR_PENDING	(1 << 0)
65 #define SLOT_INTR_PENDING(i)	(1 << (i + 1))
66 
67 /*
68  * Controller SERR-INT Register
69  */
70 #define GLOBAL_INTR_MASK	(1 << 0)
71 #define GLOBAL_SERR_MASK	(1 << 1)
72 #define COMMAND_INTR_MASK	(1 << 2)
73 #define ARBITER_SERR_MASK	(1 << 3)
74 #define COMMAND_DETECTED	(1 << 16)
75 #define ARBITER_DETECTED	(1 << 17)
76 #define SERR_INTR_RSVDZ_MASK	0xfffc0000
77 
78 /*
79  * Logical Slot Register definitions
80  */
81 #define SLOT_REG(i)		(SLOT1 + (4 * i))
82 
83 #define SLOT_STATE_SHIFT	(0)
84 #define SLOT_STATE_MASK		(3 << 0)
85 #define SLOT_STATE_PWRONLY	(1)
86 #define SLOT_STATE_ENABLED	(2)
87 #define SLOT_STATE_DISABLED	(3)
88 #define PWR_LED_STATE_SHIFT	(2)
89 #define PWR_LED_STATE_MASK	(3 << 2)
90 #define ATN_LED_STATE_SHIFT	(4)
91 #define ATN_LED_STATE_MASK	(3 << 4)
92 #define ATN_LED_STATE_ON	(1)
93 #define ATN_LED_STATE_BLINK	(2)
94 #define ATN_LED_STATE_OFF	(3)
95 #define POWER_FAULT		(1 << 6)
96 #define ATN_BUTTON		(1 << 7)
97 #define MRL_SENSOR		(1 << 8)
98 #define MHZ66_CAP		(1 << 9)
99 #define PRSNT_SHIFT		(10)
100 #define PRSNT_MASK		(3 << 10)
101 #define PCIX_CAP_SHIFT		(12)
102 #define PCIX_CAP_MASK_PI1	(3 << 12)
103 #define PCIX_CAP_MASK_PI2	(7 << 12)
104 #define PRSNT_CHANGE_DETECTED	(1 << 16)
105 #define ISO_PFAULT_DETECTED	(1 << 17)
106 #define BUTTON_PRESS_DETECTED	(1 << 18)
107 #define MRL_CHANGE_DETECTED	(1 << 19)
108 #define CON_PFAULT_DETECTED	(1 << 20)
109 #define PRSNT_CHANGE_INTR_MASK	(1 << 24)
110 #define ISO_PFAULT_INTR_MASK	(1 << 25)
111 #define BUTTON_PRESS_INTR_MASK	(1 << 26)
112 #define MRL_CHANGE_INTR_MASK	(1 << 27)
113 #define CON_PFAULT_INTR_MASK	(1 << 28)
114 #define MRL_CHANGE_SERR_MASK	(1 << 29)
115 #define CON_PFAULT_SERR_MASK	(1 << 30)
116 #define SLOT_REG_RSVDZ_MASK	((1 << 15) | (7 << 21))
117 
118 /*
119  * SHPC Command Code definitions
120  *
121  *     Slot Operation				00h - 3Fh
122  *     Set Bus Segment Speed/Mode A		40h - 47h
123  *     Power-Only All Slots			48h
124  *     Enable All Slots				49h
125  *     Set Bus Segment Speed/Mode B (PI=2)	50h - 5Fh
126  *     Reserved Command Codes			60h - BFh
127  *     Vendor Specific Commands			C0h - FFh
128  */
129 #define SET_SLOT_PWR		0x01	/* Slot Operation */
130 #define SET_SLOT_ENABLE		0x02
131 #define SET_SLOT_DISABLE	0x03
132 #define SET_PWR_ON		0x04
133 #define SET_PWR_BLINK		0x08
134 #define SET_PWR_OFF		0x0c
135 #define SET_ATTN_ON		0x10
136 #define SET_ATTN_BLINK		0x20
137 #define SET_ATTN_OFF		0x30
138 #define SETA_PCI_33MHZ		0x40	/* Set Bus Segment Speed/Mode A */
139 #define SETA_PCI_66MHZ		0x41
140 #define SETA_PCIX_66MHZ		0x42
141 #define SETA_PCIX_100MHZ	0x43
142 #define SETA_PCIX_133MHZ	0x44
143 #define SETA_RESERVED1		0x45
144 #define SETA_RESERVED2		0x46
145 #define SETA_RESERVED3		0x47
146 #define SET_PWR_ONLY_ALL	0x48	/* Power-Only All Slots */
147 #define SET_ENABLE_ALL		0x49	/* Enable All Slots */
148 #define	SETB_PCI_33MHZ		0x50	/* Set Bus Segment Speed/Mode B */
149 #define SETB_PCI_66MHZ		0x51
150 #define SETB_PCIX_66MHZ_PM	0x52
151 #define SETB_PCIX_100MHZ_PM	0x53
152 #define SETB_PCIX_133MHZ_PM	0x54
153 #define SETB_PCIX_66MHZ_EM	0x55
154 #define SETB_PCIX_100MHZ_EM	0x56
155 #define SETB_PCIX_133MHZ_EM	0x57
156 #define SETB_PCIX_66MHZ_266	0x58
157 #define SETB_PCIX_100MHZ_266	0x59
158 #define SETB_PCIX_133MHZ_266	0x5a
159 #define SETB_PCIX_66MHZ_533	0x5b
160 #define SETB_PCIX_100MHZ_533	0x5c
161 #define SETB_PCIX_133MHZ_533	0x5d
162 #define SETB_RESERVED1		0x5e
163 #define SETB_RESERVED2		0x5f
164 
165 /*
166  * SHPC controller command error code
167  */
168 #define SWITCH_OPEN		0x1
169 #define INVALID_CMD		0x2
170 #define INVALID_SPEED_MODE	0x4
171 
172 /*
173  * For accessing SHPC Working Register Set via PCI Configuration Space
174  */
175 #define DWORD_SELECT		0x2
176 #define DWORD_DATA		0x4
177 
178 /* Field Offset in Logical Slot Register - byte boundary */
179 #define SLOT_EVENT_LATCH	0x2
180 #define SLOT_SERR_INT_MASK	0x3
181 
182 static irqreturn_t shpc_isr(int irq, void *dev_id);
183 static void start_int_poll_timer(struct controller *ctrl, int sec);
184 static int hpc_check_cmd_status(struct controller *ctrl);
185 
186 static inline u8 shpc_readb(struct controller *ctrl, int reg)
187 {
188 	return readb(ctrl->creg + reg);
189 }
190 
191 static inline void shpc_writeb(struct controller *ctrl, int reg, u8 val)
192 {
193 	writeb(val, ctrl->creg + reg);
194 }
195 
196 static inline u16 shpc_readw(struct controller *ctrl, int reg)
197 {
198 	return readw(ctrl->creg + reg);
199 }
200 
201 static inline void shpc_writew(struct controller *ctrl, int reg, u16 val)
202 {
203 	writew(val, ctrl->creg + reg);
204 }
205 
206 static inline u32 shpc_readl(struct controller *ctrl, int reg)
207 {
208 	return readl(ctrl->creg + reg);
209 }
210 
211 static inline void shpc_writel(struct controller *ctrl, int reg, u32 val)
212 {
213 	writel(val, ctrl->creg + reg);
214 }
215 
216 static inline int shpc_indirect_read(struct controller *ctrl, int index,
217 				     u32 *value)
218 {
219 	int rc;
220 	u32 cap_offset = ctrl->cap_offset;
221 	struct pci_dev *pdev = ctrl->pci_dev;
222 
223 	rc = pci_write_config_byte(pdev, cap_offset + DWORD_SELECT, index);
224 	if (rc)
225 		return rc;
226 	return pci_read_config_dword(pdev, cap_offset + DWORD_DATA, value);
227 }
228 
229 /*
230  * This is the interrupt polling timeout function.
231  */
232 static void int_poll_timeout(unsigned long data)
233 {
234 	struct controller *ctrl = (struct controller *)data;
235 
236 	/* Poll for interrupt events.  regs == NULL => polling */
237 	shpc_isr(0, ctrl);
238 
239 	init_timer(&ctrl->poll_timer);
240 	if (!shpchp_poll_time)
241 		shpchp_poll_time = 2; /* default polling interval is 2 sec */
242 
243 	start_int_poll_timer(ctrl, shpchp_poll_time);
244 }
245 
246 /*
247  * This function starts the interrupt polling timer.
248  */
249 static void start_int_poll_timer(struct controller *ctrl, int sec)
250 {
251 	/* Clamp to sane value */
252 	if ((sec <= 0) || (sec > 60))
253 		sec = 2;
254 
255 	ctrl->poll_timer.function = &int_poll_timeout;
256 	ctrl->poll_timer.data = (unsigned long)ctrl;
257 	ctrl->poll_timer.expires = jiffies + sec * HZ;
258 	add_timer(&ctrl->poll_timer);
259 }
260 
261 static inline int is_ctrl_busy(struct controller *ctrl)
262 {
263 	u16 cmd_status = shpc_readw(ctrl, CMD_STATUS);
264 	return cmd_status & 0x1;
265 }
266 
267 /*
268  * Returns 1 if SHPC finishes executing a command within 1 sec,
269  * otherwise returns 0.
270  */
271 static inline int shpc_poll_ctrl_busy(struct controller *ctrl)
272 {
273 	int i;
274 
275 	if (!is_ctrl_busy(ctrl))
276 		return 1;
277 
278 	/* Check every 0.1 sec for a total of 1 sec */
279 	for (i = 0; i < 10; i++) {
280 		msleep(100);
281 		if (!is_ctrl_busy(ctrl))
282 			return 1;
283 	}
284 
285 	return 0;
286 }
287 
288 static inline int shpc_wait_cmd(struct controller *ctrl)
289 {
290 	int retval = 0;
291 	unsigned long timeout = msecs_to_jiffies(1000);
292 	int rc;
293 
294 	if (shpchp_poll_mode)
295 		rc = shpc_poll_ctrl_busy(ctrl);
296 	else
297 		rc = wait_event_interruptible_timeout(ctrl->queue,
298 						!is_ctrl_busy(ctrl), timeout);
299 	if (!rc && is_ctrl_busy(ctrl)) {
300 		retval = -EIO;
301 		ctrl_err(ctrl, "Command not completed in 1000 msec\n");
302 	} else if (rc < 0) {
303 		retval = -EINTR;
304 		ctrl_info(ctrl, "Command was interrupted by a signal\n");
305 	}
306 
307 	return retval;
308 }
309 
310 static int shpc_write_cmd(struct slot *slot, u8 t_slot, u8 cmd)
311 {
312 	struct controller *ctrl = slot->ctrl;
313 	u16 cmd_status;
314 	int retval = 0;
315 	u16 temp_word;
316 
317 	mutex_lock(&slot->ctrl->cmd_lock);
318 
319 	if (!shpc_poll_ctrl_busy(ctrl)) {
320 		/* After 1 sec and and the controller is still busy */
321 		ctrl_err(ctrl, "Controller is still busy after 1 sec\n");
322 		retval = -EBUSY;
323 		goto out;
324 	}
325 
326 	++t_slot;
327 	temp_word =  (t_slot << 8) | (cmd & 0xFF);
328 	ctrl_dbg(ctrl, "%s: t_slot %x cmd %x\n", __func__, t_slot, cmd);
329 
330 	/* To make sure the Controller Busy bit is 0 before we send out the
331 	 * command.
332 	 */
333 	shpc_writew(ctrl, CMD, temp_word);
334 
335 	/*
336 	 * Wait for command completion.
337 	 */
338 	retval = shpc_wait_cmd(slot->ctrl);
339 	if (retval)
340 		goto out;
341 
342 	cmd_status = hpc_check_cmd_status(slot->ctrl);
343 	if (cmd_status) {
344 		ctrl_err(ctrl, "Failed to issued command 0x%x (error code = %d)\n",
345 			 cmd, cmd_status);
346 		retval = -EIO;
347 	}
348  out:
349 	mutex_unlock(&slot->ctrl->cmd_lock);
350 	return retval;
351 }
352 
353 static int hpc_check_cmd_status(struct controller *ctrl)
354 {
355 	int retval = 0;
356 	u16 cmd_status = shpc_readw(ctrl, CMD_STATUS) & 0x000F;
357 
358 	switch (cmd_status >> 1) {
359 	case 0:
360 		retval = 0;
361 		break;
362 	case 1:
363 		retval = SWITCH_OPEN;
364 		ctrl_err(ctrl, "Switch opened!\n");
365 		break;
366 	case 2:
367 		retval = INVALID_CMD;
368 		ctrl_err(ctrl, "Invalid HPC command!\n");
369 		break;
370 	case 4:
371 		retval = INVALID_SPEED_MODE;
372 		ctrl_err(ctrl, "Invalid bus speed/mode!\n");
373 		break;
374 	default:
375 		retval = cmd_status;
376 	}
377 
378 	return retval;
379 }
380 
381 
382 static int hpc_get_attention_status(struct slot *slot, u8 *status)
383 {
384 	struct controller *ctrl = slot->ctrl;
385 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
386 	u8 state = (slot_reg & ATN_LED_STATE_MASK) >> ATN_LED_STATE_SHIFT;
387 
388 	switch (state) {
389 	case ATN_LED_STATE_ON:
390 		*status = 1;	/* On */
391 		break;
392 	case ATN_LED_STATE_BLINK:
393 		*status = 2;	/* Blink */
394 		break;
395 	case ATN_LED_STATE_OFF:
396 		*status = 0;	/* Off */
397 		break;
398 	default:
399 		*status = 0xFF;	/* Reserved */
400 		break;
401 	}
402 
403 	return 0;
404 }
405 
406 static int hpc_get_power_status(struct slot *slot, u8 *status)
407 {
408 	struct controller *ctrl = slot->ctrl;
409 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
410 	u8 state = (slot_reg & SLOT_STATE_MASK) >> SLOT_STATE_SHIFT;
411 
412 	switch (state) {
413 	case SLOT_STATE_PWRONLY:
414 		*status = 2;	/* Powered only */
415 		break;
416 	case SLOT_STATE_ENABLED:
417 		*status = 1;	/* Enabled */
418 		break;
419 	case SLOT_STATE_DISABLED:
420 		*status = 0;	/* Disabled */
421 		break;
422 	default:
423 		*status = 0xFF;	/* Reserved */
424 		break;
425 	}
426 
427 	return 0;
428 }
429 
430 
431 static int hpc_get_latch_status(struct slot *slot, u8 *status)
432 {
433 	struct controller *ctrl = slot->ctrl;
434 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
435 
436 	*status = !!(slot_reg & MRL_SENSOR);	/* 0 -> close; 1 -> open */
437 
438 	return 0;
439 }
440 
441 static int hpc_get_adapter_status(struct slot *slot, u8 *status)
442 {
443 	struct controller *ctrl = slot->ctrl;
444 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
445 	u8 state = (slot_reg & PRSNT_MASK) >> PRSNT_SHIFT;
446 
447 	*status = (state != 0x3) ? 1 : 0;
448 
449 	return 0;
450 }
451 
452 static int hpc_get_prog_int(struct slot *slot, u8 *prog_int)
453 {
454 	struct controller *ctrl = slot->ctrl;
455 
456 	*prog_int = shpc_readb(ctrl, PROG_INTERFACE);
457 
458 	return 0;
459 }
460 
461 static int hpc_get_adapter_speed(struct slot *slot, enum pci_bus_speed *value)
462 {
463 	int retval = 0;
464 	struct controller *ctrl = slot->ctrl;
465 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
466 	u8 m66_cap  = !!(slot_reg & MHZ66_CAP);
467 	u8 pi, pcix_cap;
468 
469 	if ((retval = hpc_get_prog_int(slot, &pi)))
470 		return retval;
471 
472 	switch (pi) {
473 	case 1:
474 		pcix_cap = (slot_reg & PCIX_CAP_MASK_PI1) >> PCIX_CAP_SHIFT;
475 		break;
476 	case 2:
477 		pcix_cap = (slot_reg & PCIX_CAP_MASK_PI2) >> PCIX_CAP_SHIFT;
478 		break;
479 	default:
480 		return -ENODEV;
481 	}
482 
483 	ctrl_dbg(ctrl, "%s: slot_reg = %x, pcix_cap = %x, m66_cap = %x\n",
484 		 __func__, slot_reg, pcix_cap, m66_cap);
485 
486 	switch (pcix_cap) {
487 	case 0x0:
488 		*value = m66_cap ? PCI_SPEED_66MHz : PCI_SPEED_33MHz;
489 		break;
490 	case 0x1:
491 		*value = PCI_SPEED_66MHz_PCIX;
492 		break;
493 	case 0x3:
494 		*value = PCI_SPEED_133MHz_PCIX;
495 		break;
496 	case 0x4:
497 		*value = PCI_SPEED_133MHz_PCIX_266;
498 		break;
499 	case 0x5:
500 		*value = PCI_SPEED_133MHz_PCIX_533;
501 		break;
502 	case 0x2:
503 	default:
504 		*value = PCI_SPEED_UNKNOWN;
505 		retval = -ENODEV;
506 		break;
507 	}
508 
509 	ctrl_dbg(ctrl, "Adapter speed = %d\n", *value);
510 	return retval;
511 }
512 
513 static int hpc_get_mode1_ECC_cap(struct slot *slot, u8 *mode)
514 {
515 	int retval = 0;
516 	struct controller *ctrl = slot->ctrl;
517 	u16 sec_bus_status = shpc_readw(ctrl, SEC_BUS_CONFIG);
518 	u8 pi = shpc_readb(ctrl, PROG_INTERFACE);
519 
520 	if (pi == 2) {
521 		*mode = (sec_bus_status & 0x0100) >> 8;
522 	} else {
523 		retval = -1;
524 	}
525 
526 	ctrl_dbg(ctrl, "Mode 1 ECC cap = %d\n", *mode);
527 	return retval;
528 }
529 
530 static int hpc_query_power_fault(struct slot *slot)
531 {
532 	struct controller *ctrl = slot->ctrl;
533 	u32 slot_reg = shpc_readl(ctrl, SLOT_REG(slot->hp_slot));
534 
535 	/* Note: Logic 0 => fault */
536 	return !(slot_reg & POWER_FAULT);
537 }
538 
539 static int hpc_set_attention_status(struct slot *slot, u8 value)
540 {
541 	u8 slot_cmd = 0;
542 
543 	switch (value) {
544 		case 0 :
545 			slot_cmd = SET_ATTN_OFF;	/* OFF */
546 			break;
547 		case 1:
548 			slot_cmd = SET_ATTN_ON;		/* ON */
549 			break;
550 		case 2:
551 			slot_cmd = SET_ATTN_BLINK;	/* BLINK */
552 			break;
553 		default:
554 			return -1;
555 	}
556 
557 	return shpc_write_cmd(slot, slot->hp_slot, slot_cmd);
558 }
559 
560 
561 static void hpc_set_green_led_on(struct slot *slot)
562 {
563 	shpc_write_cmd(slot, slot->hp_slot, SET_PWR_ON);
564 }
565 
566 static void hpc_set_green_led_off(struct slot *slot)
567 {
568 	shpc_write_cmd(slot, slot->hp_slot, SET_PWR_OFF);
569 }
570 
571 static void hpc_set_green_led_blink(struct slot *slot)
572 {
573 	shpc_write_cmd(slot, slot->hp_slot, SET_PWR_BLINK);
574 }
575 
576 static void hpc_release_ctlr(struct controller *ctrl)
577 {
578 	int i;
579 	u32 slot_reg, serr_int;
580 
581 	/*
582 	 * Mask event interrupts and SERRs of all slots
583 	 */
584 	for (i = 0; i < ctrl->num_slots; i++) {
585 		slot_reg = shpc_readl(ctrl, SLOT_REG(i));
586 		slot_reg |= (PRSNT_CHANGE_INTR_MASK | ISO_PFAULT_INTR_MASK |
587 			     BUTTON_PRESS_INTR_MASK | MRL_CHANGE_INTR_MASK |
588 			     CON_PFAULT_INTR_MASK   | MRL_CHANGE_SERR_MASK |
589 			     CON_PFAULT_SERR_MASK);
590 		slot_reg &= ~SLOT_REG_RSVDZ_MASK;
591 		shpc_writel(ctrl, SLOT_REG(i), slot_reg);
592 	}
593 
594 	cleanup_slots(ctrl);
595 
596 	/*
597 	 * Mask SERR and System Interrupt generation
598 	 */
599 	serr_int = shpc_readl(ctrl, SERR_INTR_ENABLE);
600 	serr_int |= (GLOBAL_INTR_MASK  | GLOBAL_SERR_MASK |
601 		     COMMAND_INTR_MASK | ARBITER_SERR_MASK);
602 	serr_int &= ~SERR_INTR_RSVDZ_MASK;
603 	shpc_writel(ctrl, SERR_INTR_ENABLE, serr_int);
604 
605 	if (shpchp_poll_mode)
606 		del_timer(&ctrl->poll_timer);
607 	else {
608 		free_irq(ctrl->pci_dev->irq, ctrl);
609 		pci_disable_msi(ctrl->pci_dev);
610 	}
611 
612 	iounmap(ctrl->creg);
613 	release_mem_region(ctrl->mmio_base, ctrl->mmio_size);
614 }
615 
616 static int hpc_power_on_slot(struct slot *slot)
617 {
618 	int retval;
619 
620 	retval = shpc_write_cmd(slot, slot->hp_slot, SET_SLOT_PWR);
621 	if (retval)
622 		ctrl_err(slot->ctrl, "%s: Write command failed!\n", __func__);
623 
624 	return retval;
625 }
626 
627 static int hpc_slot_enable(struct slot *slot)
628 {
629 	int retval;
630 
631 	/* Slot - Enable, Power Indicator - Blink, Attention Indicator - Off */
632 	retval = shpc_write_cmd(slot, slot->hp_slot,
633 			SET_SLOT_ENABLE | SET_PWR_BLINK | SET_ATTN_OFF);
634 	if (retval)
635 		ctrl_err(slot->ctrl, "%s: Write command failed!\n", __func__);
636 
637 	return retval;
638 }
639 
640 static int hpc_slot_disable(struct slot *slot)
641 {
642 	int retval;
643 
644 	/* Slot - Disable, Power Indicator - Off, Attention Indicator - On */
645 	retval = shpc_write_cmd(slot, slot->hp_slot,
646 			SET_SLOT_DISABLE | SET_PWR_OFF | SET_ATTN_ON);
647 	if (retval)
648 		ctrl_err(slot->ctrl, "%s: Write command failed!\n", __func__);
649 
650 	return retval;
651 }
652 
653 static int shpc_get_cur_bus_speed(struct controller *ctrl)
654 {
655 	int retval = 0;
656 	struct pci_bus *bus = ctrl->pci_dev->subordinate;
657 	enum pci_bus_speed bus_speed = PCI_SPEED_UNKNOWN;
658 	u16 sec_bus_reg = shpc_readw(ctrl, SEC_BUS_CONFIG);
659 	u8 pi = shpc_readb(ctrl, PROG_INTERFACE);
660 	u8 speed_mode = (pi == 2) ? (sec_bus_reg & 0xF) : (sec_bus_reg & 0x7);
661 
662 	if ((pi == 1) && (speed_mode > 4)) {
663 		retval = -ENODEV;
664 		goto out;
665 	}
666 
667 	switch (speed_mode) {
668 	case 0x0:
669 		bus_speed = PCI_SPEED_33MHz;
670 		break;
671 	case 0x1:
672 		bus_speed = PCI_SPEED_66MHz;
673 		break;
674 	case 0x2:
675 		bus_speed = PCI_SPEED_66MHz_PCIX;
676 		break;
677 	case 0x3:
678 		bus_speed = PCI_SPEED_100MHz_PCIX;
679 		break;
680 	case 0x4:
681 		bus_speed = PCI_SPEED_133MHz_PCIX;
682 		break;
683 	case 0x5:
684 		bus_speed = PCI_SPEED_66MHz_PCIX_ECC;
685 		break;
686 	case 0x6:
687 		bus_speed = PCI_SPEED_100MHz_PCIX_ECC;
688 		break;
689 	case 0x7:
690 		bus_speed = PCI_SPEED_133MHz_PCIX_ECC;
691 		break;
692 	case 0x8:
693 		bus_speed = PCI_SPEED_66MHz_PCIX_266;
694 		break;
695 	case 0x9:
696 		bus_speed = PCI_SPEED_100MHz_PCIX_266;
697 		break;
698 	case 0xa:
699 		bus_speed = PCI_SPEED_133MHz_PCIX_266;
700 		break;
701 	case 0xb:
702 		bus_speed = PCI_SPEED_66MHz_PCIX_533;
703 		break;
704 	case 0xc:
705 		bus_speed = PCI_SPEED_100MHz_PCIX_533;
706 		break;
707 	case 0xd:
708 		bus_speed = PCI_SPEED_133MHz_PCIX_533;
709 		break;
710 	default:
711 		retval = -ENODEV;
712 		break;
713 	}
714 
715  out:
716 	bus->cur_bus_speed = bus_speed;
717 	dbg("Current bus speed = %d\n", bus_speed);
718 	return retval;
719 }
720 
721 
722 static int hpc_set_bus_speed_mode(struct slot *slot, enum pci_bus_speed value)
723 {
724 	int retval;
725 	struct controller *ctrl = slot->ctrl;
726 	u8 pi, cmd;
727 
728 	pi = shpc_readb(ctrl, PROG_INTERFACE);
729 	if ((pi == 1) && (value > PCI_SPEED_133MHz_PCIX))
730 		return -EINVAL;
731 
732 	switch (value) {
733 	case PCI_SPEED_33MHz:
734 		cmd = SETA_PCI_33MHZ;
735 		break;
736 	case PCI_SPEED_66MHz:
737 		cmd = SETA_PCI_66MHZ;
738 		break;
739 	case PCI_SPEED_66MHz_PCIX:
740 		cmd = SETA_PCIX_66MHZ;
741 		break;
742 	case PCI_SPEED_100MHz_PCIX:
743 		cmd = SETA_PCIX_100MHZ;
744 		break;
745 	case PCI_SPEED_133MHz_PCIX:
746 		cmd = SETA_PCIX_133MHZ;
747 		break;
748 	case PCI_SPEED_66MHz_PCIX_ECC:
749 		cmd = SETB_PCIX_66MHZ_EM;
750 		break;
751 	case PCI_SPEED_100MHz_PCIX_ECC:
752 		cmd = SETB_PCIX_100MHZ_EM;
753 		break;
754 	case PCI_SPEED_133MHz_PCIX_ECC:
755 		cmd = SETB_PCIX_133MHZ_EM;
756 		break;
757 	case PCI_SPEED_66MHz_PCIX_266:
758 		cmd = SETB_PCIX_66MHZ_266;
759 		break;
760 	case PCI_SPEED_100MHz_PCIX_266:
761 		cmd = SETB_PCIX_100MHZ_266;
762 		break;
763 	case PCI_SPEED_133MHz_PCIX_266:
764 		cmd = SETB_PCIX_133MHZ_266;
765 		break;
766 	case PCI_SPEED_66MHz_PCIX_533:
767 		cmd = SETB_PCIX_66MHZ_533;
768 		break;
769 	case PCI_SPEED_100MHz_PCIX_533:
770 		cmd = SETB_PCIX_100MHZ_533;
771 		break;
772 	case PCI_SPEED_133MHz_PCIX_533:
773 		cmd = SETB_PCIX_133MHZ_533;
774 		break;
775 	default:
776 		return -EINVAL;
777 	}
778 
779 	retval = shpc_write_cmd(slot, 0, cmd);
780 	if (retval)
781 		ctrl_err(ctrl, "%s: Write command failed!\n", __func__);
782 	else
783 		shpc_get_cur_bus_speed(ctrl);
784 
785 	return retval;
786 }
787 
788 static irqreturn_t shpc_isr(int irq, void *dev_id)
789 {
790 	struct controller *ctrl = (struct controller *)dev_id;
791 	u32 serr_int, slot_reg, intr_loc, intr_loc2;
792 	int hp_slot;
793 
794 	/* Check to see if it was our interrupt */
795 	intr_loc = shpc_readl(ctrl, INTR_LOC);
796 	if (!intr_loc)
797 		return IRQ_NONE;
798 
799 	ctrl_dbg(ctrl, "%s: intr_loc = %x\n", __func__, intr_loc);
800 
801 	if(!shpchp_poll_mode) {
802 		/*
803 		 * Mask Global Interrupt Mask - see implementation
804 		 * note on p. 139 of SHPC spec rev 1.0
805 		 */
806 		serr_int = shpc_readl(ctrl, SERR_INTR_ENABLE);
807 		serr_int |= GLOBAL_INTR_MASK;
808 		serr_int &= ~SERR_INTR_RSVDZ_MASK;
809 		shpc_writel(ctrl, SERR_INTR_ENABLE, serr_int);
810 
811 		intr_loc2 = shpc_readl(ctrl, INTR_LOC);
812 		ctrl_dbg(ctrl, "%s: intr_loc2 = %x\n", __func__, intr_loc2);
813 	}
814 
815 	if (intr_loc & CMD_INTR_PENDING) {
816 		/*
817 		 * Command Complete Interrupt Pending
818 		 * RO only - clear by writing 1 to the Command Completion
819 		 * Detect bit in Controller SERR-INT register
820 		 */
821 		serr_int = shpc_readl(ctrl, SERR_INTR_ENABLE);
822 		serr_int &= ~SERR_INTR_RSVDZ_MASK;
823 		shpc_writel(ctrl, SERR_INTR_ENABLE, serr_int);
824 
825 		wake_up_interruptible(&ctrl->queue);
826 	}
827 
828 	if (!(intr_loc & ~CMD_INTR_PENDING))
829 		goto out;
830 
831 	for (hp_slot = 0; hp_slot < ctrl->num_slots; hp_slot++) {
832 		/* To find out which slot has interrupt pending */
833 		if (!(intr_loc & SLOT_INTR_PENDING(hp_slot)))
834 			continue;
835 
836 		slot_reg = shpc_readl(ctrl, SLOT_REG(hp_slot));
837 		ctrl_dbg(ctrl, "Slot %x with intr, slot register = %x\n",
838 			 hp_slot, slot_reg);
839 
840 		if (slot_reg & MRL_CHANGE_DETECTED)
841 			shpchp_handle_switch_change(hp_slot, ctrl);
842 
843 		if (slot_reg & BUTTON_PRESS_DETECTED)
844 			shpchp_handle_attention_button(hp_slot, ctrl);
845 
846 		if (slot_reg & PRSNT_CHANGE_DETECTED)
847 			shpchp_handle_presence_change(hp_slot, ctrl);
848 
849 		if (slot_reg & (ISO_PFAULT_DETECTED | CON_PFAULT_DETECTED))
850 			shpchp_handle_power_fault(hp_slot, ctrl);
851 
852 		/* Clear all slot events */
853 		slot_reg &= ~SLOT_REG_RSVDZ_MASK;
854 		shpc_writel(ctrl, SLOT_REG(hp_slot), slot_reg);
855 	}
856  out:
857 	if (!shpchp_poll_mode) {
858 		/* Unmask Global Interrupt Mask */
859 		serr_int = shpc_readl(ctrl, SERR_INTR_ENABLE);
860 		serr_int &= ~(GLOBAL_INTR_MASK | SERR_INTR_RSVDZ_MASK);
861 		shpc_writel(ctrl, SERR_INTR_ENABLE, serr_int);
862 	}
863 
864 	return IRQ_HANDLED;
865 }
866 
867 static int shpc_get_max_bus_speed(struct controller *ctrl)
868 {
869 	int retval = 0;
870 	struct pci_bus *bus = ctrl->pci_dev->subordinate;
871 	enum pci_bus_speed bus_speed = PCI_SPEED_UNKNOWN;
872 	u8 pi = shpc_readb(ctrl, PROG_INTERFACE);
873 	u32 slot_avail1 = shpc_readl(ctrl, SLOT_AVAIL1);
874 	u32 slot_avail2 = shpc_readl(ctrl, SLOT_AVAIL2);
875 
876 	if (pi == 2) {
877 		if (slot_avail2 & SLOT_133MHZ_PCIX_533)
878 			bus_speed = PCI_SPEED_133MHz_PCIX_533;
879 		else if (slot_avail2 & SLOT_100MHZ_PCIX_533)
880 			bus_speed = PCI_SPEED_100MHz_PCIX_533;
881 		else if (slot_avail2 & SLOT_66MHZ_PCIX_533)
882 			bus_speed = PCI_SPEED_66MHz_PCIX_533;
883 		else if (slot_avail2 & SLOT_133MHZ_PCIX_266)
884 			bus_speed = PCI_SPEED_133MHz_PCIX_266;
885 		else if (slot_avail2 & SLOT_100MHZ_PCIX_266)
886 			bus_speed = PCI_SPEED_100MHz_PCIX_266;
887 		else if (slot_avail2 & SLOT_66MHZ_PCIX_266)
888 			bus_speed = PCI_SPEED_66MHz_PCIX_266;
889 	}
890 
891 	if (bus_speed == PCI_SPEED_UNKNOWN) {
892 		if (slot_avail1 & SLOT_133MHZ_PCIX)
893 			bus_speed = PCI_SPEED_133MHz_PCIX;
894 		else if (slot_avail1 & SLOT_100MHZ_PCIX)
895 			bus_speed = PCI_SPEED_100MHz_PCIX;
896 		else if (slot_avail1 & SLOT_66MHZ_PCIX)
897 			bus_speed = PCI_SPEED_66MHz_PCIX;
898 		else if (slot_avail2 & SLOT_66MHZ)
899 			bus_speed = PCI_SPEED_66MHz;
900 		else if (slot_avail1 & SLOT_33MHZ)
901 			bus_speed = PCI_SPEED_33MHz;
902 		else
903 			retval = -ENODEV;
904 	}
905 
906 	bus->max_bus_speed = bus_speed;
907 	ctrl_dbg(ctrl, "Max bus speed = %d\n", bus_speed);
908 
909 	return retval;
910 }
911 
912 static struct hpc_ops shpchp_hpc_ops = {
913 	.power_on_slot			= hpc_power_on_slot,
914 	.slot_enable			= hpc_slot_enable,
915 	.slot_disable			= hpc_slot_disable,
916 	.set_bus_speed_mode		= hpc_set_bus_speed_mode,
917 	.set_attention_status	= hpc_set_attention_status,
918 	.get_power_status		= hpc_get_power_status,
919 	.get_attention_status	= hpc_get_attention_status,
920 	.get_latch_status		= hpc_get_latch_status,
921 	.get_adapter_status		= hpc_get_adapter_status,
922 
923 	.get_adapter_speed		= hpc_get_adapter_speed,
924 	.get_mode1_ECC_cap		= hpc_get_mode1_ECC_cap,
925 	.get_prog_int			= hpc_get_prog_int,
926 
927 	.query_power_fault		= hpc_query_power_fault,
928 	.green_led_on			= hpc_set_green_led_on,
929 	.green_led_off			= hpc_set_green_led_off,
930 	.green_led_blink		= hpc_set_green_led_blink,
931 
932 	.release_ctlr			= hpc_release_ctlr,
933 };
934 
935 int shpc_init(struct controller *ctrl, struct pci_dev *pdev)
936 {
937 	int rc = -1, num_slots = 0;
938 	u8 hp_slot;
939 	u32 shpc_base_offset;
940 	u32 tempdword, slot_reg, slot_config;
941 	u8 i;
942 
943 	ctrl->pci_dev = pdev;  /* pci_dev of the P2P bridge */
944 	ctrl_dbg(ctrl, "Hotplug Controller:\n");
945 
946 	if (pdev->vendor == PCI_VENDOR_ID_AMD &&
947 	    pdev->device == PCI_DEVICE_ID_AMD_GOLAM_7450) {
948 		/* amd shpc driver doesn't use Base Offset; assume 0 */
949 		ctrl->mmio_base = pci_resource_start(pdev, 0);
950 		ctrl->mmio_size = pci_resource_len(pdev, 0);
951 	} else {
952 		ctrl->cap_offset = pci_find_capability(pdev, PCI_CAP_ID_SHPC);
953 		if (!ctrl->cap_offset) {
954 			ctrl_err(ctrl, "Cannot find PCI capability\n");
955 			goto abort;
956 		}
957 		ctrl_dbg(ctrl, " cap_offset = %x\n", ctrl->cap_offset);
958 
959 		rc = shpc_indirect_read(ctrl, 0, &shpc_base_offset);
960 		if (rc) {
961 			ctrl_err(ctrl, "Cannot read base_offset\n");
962 			goto abort;
963 		}
964 
965 		rc = shpc_indirect_read(ctrl, 3, &tempdword);
966 		if (rc) {
967 			ctrl_err(ctrl, "Cannot read slot config\n");
968 			goto abort;
969 		}
970 		num_slots = tempdword & SLOT_NUM;
971 		ctrl_dbg(ctrl, " num_slots (indirect) %x\n", num_slots);
972 
973 		for (i = 0; i < 9 + num_slots; i++) {
974 			rc = shpc_indirect_read(ctrl, i, &tempdword);
975 			if (rc) {
976 				ctrl_err(ctrl, "Cannot read creg (index = %d)\n",
977 					 i);
978 				goto abort;
979 			}
980 			ctrl_dbg(ctrl, " offset %d: value %x\n", i, tempdword);
981 		}
982 
983 		ctrl->mmio_base =
984 			pci_resource_start(pdev, 0) + shpc_base_offset;
985 		ctrl->mmio_size = 0x24 + 0x4 * num_slots;
986 	}
987 
988 	ctrl_info(ctrl, "HPC vendor_id %x device_id %x ss_vid %x ss_did %x\n",
989 		  pdev->vendor, pdev->device, pdev->subsystem_vendor,
990 		  pdev->subsystem_device);
991 
992 	rc = pci_enable_device(pdev);
993 	if (rc) {
994 		ctrl_err(ctrl, "pci_enable_device failed\n");
995 		goto abort;
996 	}
997 
998 	if (!request_mem_region(ctrl->mmio_base, ctrl->mmio_size, MY_NAME)) {
999 		ctrl_err(ctrl, "Cannot reserve MMIO region\n");
1000 		rc = -1;
1001 		goto abort;
1002 	}
1003 
1004 	ctrl->creg = ioremap(ctrl->mmio_base, ctrl->mmio_size);
1005 	if (!ctrl->creg) {
1006 		ctrl_err(ctrl, "Cannot remap MMIO region %lx @ %lx\n",
1007 			 ctrl->mmio_size, ctrl->mmio_base);
1008 		release_mem_region(ctrl->mmio_base, ctrl->mmio_size);
1009 		rc = -1;
1010 		goto abort;
1011 	}
1012 	ctrl_dbg(ctrl, "ctrl->creg %p\n", ctrl->creg);
1013 
1014 	mutex_init(&ctrl->crit_sect);
1015 	mutex_init(&ctrl->cmd_lock);
1016 
1017 	/* Setup wait queue */
1018 	init_waitqueue_head(&ctrl->queue);
1019 
1020 	ctrl->hpc_ops = &shpchp_hpc_ops;
1021 
1022 	/* Return PCI Controller Info */
1023 	slot_config = shpc_readl(ctrl, SLOT_CONFIG);
1024 	ctrl->slot_device_offset = (slot_config & FIRST_DEV_NUM) >> 8;
1025 	ctrl->num_slots = slot_config & SLOT_NUM;
1026 	ctrl->first_slot = (slot_config & PSN) >> 16;
1027 	ctrl->slot_num_inc = ((slot_config & UPDOWN) >> 29) ? 1 : -1;
1028 
1029 	/* Mask Global Interrupt Mask & Command Complete Interrupt Mask */
1030 	tempdword = shpc_readl(ctrl, SERR_INTR_ENABLE);
1031 	ctrl_dbg(ctrl, "SERR_INTR_ENABLE = %x\n", tempdword);
1032 	tempdword |= (GLOBAL_INTR_MASK  | GLOBAL_SERR_MASK |
1033 		      COMMAND_INTR_MASK | ARBITER_SERR_MASK);
1034 	tempdword &= ~SERR_INTR_RSVDZ_MASK;
1035 	shpc_writel(ctrl, SERR_INTR_ENABLE, tempdword);
1036 	tempdword = shpc_readl(ctrl, SERR_INTR_ENABLE);
1037 	ctrl_dbg(ctrl, "SERR_INTR_ENABLE = %x\n", tempdword);
1038 
1039 	/* Mask the MRL sensor SERR Mask of individual slot in
1040 	 * Slot SERR-INT Mask & clear all the existing event if any
1041 	 */
1042 	for (hp_slot = 0; hp_slot < ctrl->num_slots; hp_slot++) {
1043 		slot_reg = shpc_readl(ctrl, SLOT_REG(hp_slot));
1044 		ctrl_dbg(ctrl, "Default Logical Slot Register %d value %x\n",
1045 			 hp_slot, slot_reg);
1046 		slot_reg |= (PRSNT_CHANGE_INTR_MASK | ISO_PFAULT_INTR_MASK |
1047 			     BUTTON_PRESS_INTR_MASK | MRL_CHANGE_INTR_MASK |
1048 			     CON_PFAULT_INTR_MASK   | MRL_CHANGE_SERR_MASK |
1049 			     CON_PFAULT_SERR_MASK);
1050 		slot_reg &= ~SLOT_REG_RSVDZ_MASK;
1051 		shpc_writel(ctrl, SLOT_REG(hp_slot), slot_reg);
1052 	}
1053 
1054 	if (shpchp_poll_mode) {
1055 		/* Install interrupt polling timer. Start with 10 sec delay */
1056 		init_timer(&ctrl->poll_timer);
1057 		start_int_poll_timer(ctrl, 10);
1058 	} else {
1059 		/* Installs the interrupt handler */
1060 		rc = pci_enable_msi(pdev);
1061 		if (rc) {
1062 			ctrl_info(ctrl, "Can't get msi for the hotplug controller\n");
1063 			ctrl_info(ctrl, "Use INTx for the hotplug controller\n");
1064 		}
1065 
1066 		rc = request_irq(ctrl->pci_dev->irq, shpc_isr, IRQF_SHARED,
1067 				 MY_NAME, (void *)ctrl);
1068 		ctrl_dbg(ctrl, "request_irq %d (returns %d)\n",
1069 			 ctrl->pci_dev->irq, rc);
1070 		if (rc) {
1071 			ctrl_err(ctrl, "Can't get irq %d for the hotplug controller\n",
1072 				 ctrl->pci_dev->irq);
1073 			goto abort_iounmap;
1074 		}
1075 	}
1076 	ctrl_dbg(ctrl, "HPC at %s irq=%x\n", pci_name(pdev), pdev->irq);
1077 
1078 	shpc_get_max_bus_speed(ctrl);
1079 	shpc_get_cur_bus_speed(ctrl);
1080 
1081 	/*
1082 	 * Unmask all event interrupts of all slots
1083 	 */
1084 	for (hp_slot = 0; hp_slot < ctrl->num_slots; hp_slot++) {
1085 		slot_reg = shpc_readl(ctrl, SLOT_REG(hp_slot));
1086 		ctrl_dbg(ctrl, "Default Logical Slot Register %d value %x\n",
1087 			 hp_slot, slot_reg);
1088 		slot_reg &= ~(PRSNT_CHANGE_INTR_MASK | ISO_PFAULT_INTR_MASK |
1089 			      BUTTON_PRESS_INTR_MASK | MRL_CHANGE_INTR_MASK |
1090 			      CON_PFAULT_INTR_MASK | SLOT_REG_RSVDZ_MASK);
1091 		shpc_writel(ctrl, SLOT_REG(hp_slot), slot_reg);
1092 	}
1093 	if (!shpchp_poll_mode) {
1094 		/* Unmask all general input interrupts and SERR */
1095 		tempdword = shpc_readl(ctrl, SERR_INTR_ENABLE);
1096 		tempdword &= ~(GLOBAL_INTR_MASK | COMMAND_INTR_MASK |
1097 			       SERR_INTR_RSVDZ_MASK);
1098 		shpc_writel(ctrl, SERR_INTR_ENABLE, tempdword);
1099 		tempdword = shpc_readl(ctrl, SERR_INTR_ENABLE);
1100 		ctrl_dbg(ctrl, "SERR_INTR_ENABLE = %x\n", tempdword);
1101 	}
1102 
1103 	return 0;
1104 
1105 	/* We end up here for the many possible ways to fail this API.  */
1106 abort_iounmap:
1107 	iounmap(ctrl->creg);
1108 abort:
1109 	return rc;
1110 }
1111