• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * PCI Express 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/signal.h>
34 #include <linux/jiffies.h>
35 #include <linux/timer.h>
36 #include <linux/pci.h>
37 #include <linux/interrupt.h>
38 #include <linux/time.h>
39 #include <linux/slab.h>
40 
41 #include "../pci.h"
42 #include "pciehp.h"
43 
ctrl_dev(struct controller * ctrl)44 static inline struct pci_dev *ctrl_dev(struct controller *ctrl)
45 {
46 	return ctrl->pcie->port;
47 }
48 
49 static irqreturn_t pcie_isr(int irq, void *dev_id);
50 static void start_int_poll_timer(struct controller *ctrl, int sec);
51 
52 /* This is the interrupt polling timeout function. */
int_poll_timeout(unsigned long data)53 static void int_poll_timeout(unsigned long data)
54 {
55 	struct controller *ctrl = (struct controller *)data;
56 
57 	/* Poll for interrupt events.  regs == NULL => polling */
58 	pcie_isr(0, ctrl);
59 
60 	init_timer(&ctrl->poll_timer);
61 	if (!pciehp_poll_time)
62 		pciehp_poll_time = 2; /* default polling interval is 2 sec */
63 
64 	start_int_poll_timer(ctrl, pciehp_poll_time);
65 }
66 
67 /* This function starts the interrupt polling timer. */
start_int_poll_timer(struct controller * ctrl,int sec)68 static void start_int_poll_timer(struct controller *ctrl, int sec)
69 {
70 	/* Clamp to sane value */
71 	if ((sec <= 0) || (sec > 60))
72 		sec = 2;
73 
74 	ctrl->poll_timer.function = &int_poll_timeout;
75 	ctrl->poll_timer.data = (unsigned long)ctrl;
76 	ctrl->poll_timer.expires = jiffies + sec * HZ;
77 	add_timer(&ctrl->poll_timer);
78 }
79 
pciehp_request_irq(struct controller * ctrl)80 static inline int pciehp_request_irq(struct controller *ctrl)
81 {
82 	int retval, irq = ctrl->pcie->irq;
83 
84 	/* Install interrupt polling timer. Start with 10 sec delay */
85 	if (pciehp_poll_mode) {
86 		init_timer(&ctrl->poll_timer);
87 		start_int_poll_timer(ctrl, 10);
88 		return 0;
89 	}
90 
91 	/* Installs the interrupt handler */
92 	retval = request_irq(irq, pcie_isr, IRQF_SHARED, MY_NAME, ctrl);
93 	if (retval)
94 		ctrl_err(ctrl, "Cannot get irq %d for the hotplug controller\n",
95 			 irq);
96 	return retval;
97 }
98 
pciehp_free_irq(struct controller * ctrl)99 static inline void pciehp_free_irq(struct controller *ctrl)
100 {
101 	if (pciehp_poll_mode)
102 		del_timer_sync(&ctrl->poll_timer);
103 	else
104 		free_irq(ctrl->pcie->irq, ctrl);
105 }
106 
pcie_poll_cmd(struct controller * ctrl,int timeout)107 static int pcie_poll_cmd(struct controller *ctrl, int timeout)
108 {
109 	struct pci_dev *pdev = ctrl_dev(ctrl);
110 	u16 slot_status;
111 
112 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
113 	if (slot_status & PCI_EXP_SLTSTA_CC) {
114 		pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
115 					   PCI_EXP_SLTSTA_CC);
116 		return 1;
117 	}
118 	while (timeout > 0) {
119 		msleep(10);
120 		timeout -= 10;
121 		pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
122 		if (slot_status & PCI_EXP_SLTSTA_CC) {
123 			pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
124 						   PCI_EXP_SLTSTA_CC);
125 			return 1;
126 		}
127 	}
128 	return 0;	/* timeout */
129 }
130 
pcie_wait_cmd(struct controller * ctrl)131 static void pcie_wait_cmd(struct controller *ctrl)
132 {
133 	unsigned int msecs = pciehp_poll_mode ? 2500 : 1000;
134 	unsigned long duration = msecs_to_jiffies(msecs);
135 	unsigned long cmd_timeout = ctrl->cmd_started + duration;
136 	unsigned long now, timeout;
137 	int rc;
138 
139 	/*
140 	 * If the controller does not generate notifications for command
141 	 * completions, we never need to wait between writes.
142 	 */
143 	if (NO_CMD_CMPL(ctrl))
144 		return;
145 
146 	if (!ctrl->cmd_busy)
147 		return;
148 
149 	/*
150 	 * Even if the command has already timed out, we want to call
151 	 * pcie_poll_cmd() so it can clear PCI_EXP_SLTSTA_CC.
152 	 */
153 	now = jiffies;
154 	if (time_before_eq(cmd_timeout, now))
155 		timeout = 1;
156 	else
157 		timeout = cmd_timeout - now;
158 
159 	if (ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE &&
160 	    ctrl->slot_ctrl & PCI_EXP_SLTCTL_CCIE)
161 		rc = wait_event_timeout(ctrl->queue, !ctrl->cmd_busy, timeout);
162 	else
163 		rc = pcie_poll_cmd(ctrl, jiffies_to_msecs(timeout));
164 
165 	/*
166 	 * Controllers with errata like Intel CF118 don't generate
167 	 * completion notifications unless the power/indicator/interlock
168 	 * control bits are changed.  On such controllers, we'll emit this
169 	 * timeout message when we wait for completion of commands that
170 	 * don't change those bits, e.g., commands that merely enable
171 	 * interrupts.
172 	 */
173 	if (!rc)
174 		ctrl_info(ctrl, "Timeout on hotplug command %#06x (issued %u msec ago)\n",
175 			  ctrl->slot_ctrl,
176 			  jiffies_to_msecs(jiffies - ctrl->cmd_started));
177 }
178 
pcie_do_write_cmd(struct controller * ctrl,u16 cmd,u16 mask,bool wait)179 static void pcie_do_write_cmd(struct controller *ctrl, u16 cmd,
180 			      u16 mask, bool wait)
181 {
182 	struct pci_dev *pdev = ctrl_dev(ctrl);
183 	u16 slot_ctrl;
184 
185 	mutex_lock(&ctrl->ctrl_lock);
186 
187 	/*
188 	 * Always wait for any previous command that might still be in progress
189 	 */
190 	pcie_wait_cmd(ctrl);
191 
192 	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
193 	slot_ctrl &= ~mask;
194 	slot_ctrl |= (cmd & mask);
195 	ctrl->cmd_busy = 1;
196 	smp_mb();
197 	pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, slot_ctrl);
198 	ctrl->cmd_started = jiffies;
199 	ctrl->slot_ctrl = slot_ctrl;
200 
201 	/*
202 	 * Optionally wait for the hardware to be ready for a new command,
203 	 * indicating completion of the above issued command.
204 	 */
205 	if (wait)
206 		pcie_wait_cmd(ctrl);
207 
208 	mutex_unlock(&ctrl->ctrl_lock);
209 }
210 
211 /**
212  * pcie_write_cmd - Issue controller command
213  * @ctrl: controller to which the command is issued
214  * @cmd:  command value written to slot control register
215  * @mask: bitmask of slot control register to be modified
216  */
pcie_write_cmd(struct controller * ctrl,u16 cmd,u16 mask)217 static void pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask)
218 {
219 	pcie_do_write_cmd(ctrl, cmd, mask, true);
220 }
221 
222 /* Same as above without waiting for the hardware to latch */
pcie_write_cmd_nowait(struct controller * ctrl,u16 cmd,u16 mask)223 static void pcie_write_cmd_nowait(struct controller *ctrl, u16 cmd, u16 mask)
224 {
225 	pcie_do_write_cmd(ctrl, cmd, mask, false);
226 }
227 
pciehp_check_link_active(struct controller * ctrl)228 bool pciehp_check_link_active(struct controller *ctrl)
229 {
230 	struct pci_dev *pdev = ctrl_dev(ctrl);
231 	u16 lnk_status;
232 	bool ret;
233 
234 	pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
235 	ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
236 
237 	if (ret)
238 		ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
239 
240 	return ret;
241 }
242 
__pcie_wait_link_active(struct controller * ctrl,bool active)243 static void __pcie_wait_link_active(struct controller *ctrl, bool active)
244 {
245 	int timeout = 1000;
246 
247 	if (pciehp_check_link_active(ctrl) == active)
248 		return;
249 	while (timeout > 0) {
250 		msleep(10);
251 		timeout -= 10;
252 		if (pciehp_check_link_active(ctrl) == active)
253 			return;
254 	}
255 	ctrl_dbg(ctrl, "Data Link Layer Link Active not %s in 1000 msec\n",
256 			active ? "set" : "cleared");
257 }
258 
pcie_wait_link_active(struct controller * ctrl)259 static void pcie_wait_link_active(struct controller *ctrl)
260 {
261 	__pcie_wait_link_active(ctrl, true);
262 }
263 
pci_bus_check_dev(struct pci_bus * bus,int devfn)264 static bool pci_bus_check_dev(struct pci_bus *bus, int devfn)
265 {
266 	u32 l;
267 	int count = 0;
268 	int delay = 1000, step = 20;
269 	bool found = false;
270 
271 	do {
272 		found = pci_bus_read_dev_vendor_id(bus, devfn, &l, 0);
273 		count++;
274 
275 		if (found)
276 			break;
277 
278 		msleep(step);
279 		delay -= step;
280 	} while (delay > 0);
281 
282 	if (count > 1 && pciehp_debug)
283 		printk(KERN_DEBUG "pci %04x:%02x:%02x.%d id reading try %d times with interval %d ms to get %08x\n",
284 			pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
285 			PCI_FUNC(devfn), count, step, l);
286 
287 	return found;
288 }
289 
pciehp_check_link_status(struct controller * ctrl)290 int pciehp_check_link_status(struct controller *ctrl)
291 {
292 	struct pci_dev *pdev = ctrl_dev(ctrl);
293 	bool found;
294 	u16 lnk_status;
295 
296 	/*
297 	 * Data Link Layer Link Active Reporting must be capable for
298 	 * hot-plug capable downstream port. But old controller might
299 	 * not implement it. In this case, we wait for 1000 ms.
300 	*/
301 	if (ctrl->link_active_reporting)
302 		pcie_wait_link_active(ctrl);
303 	else
304 		msleep(1000);
305 
306 	/* wait 100ms before read pci conf, and try in 1s */
307 	msleep(100);
308 	found = pci_bus_check_dev(ctrl->pcie->port->subordinate,
309 					PCI_DEVFN(0, 0));
310 
311 	pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
312 	ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
313 	if ((lnk_status & PCI_EXP_LNKSTA_LT) ||
314 	    !(lnk_status & PCI_EXP_LNKSTA_NLW)) {
315 		ctrl_err(ctrl, "Link Training Error occurs\n");
316 		return -1;
317 	}
318 
319 	pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
320 
321 	if (!found)
322 		return -1;
323 
324 	return 0;
325 }
326 
__pciehp_link_set(struct controller * ctrl,bool enable)327 static int __pciehp_link_set(struct controller *ctrl, bool enable)
328 {
329 	struct pci_dev *pdev = ctrl_dev(ctrl);
330 	u16 lnk_ctrl;
331 
332 	pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnk_ctrl);
333 
334 	if (enable)
335 		lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
336 	else
337 		lnk_ctrl |= PCI_EXP_LNKCTL_LD;
338 
339 	pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnk_ctrl);
340 	ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
341 	return 0;
342 }
343 
pciehp_link_enable(struct controller * ctrl)344 static int pciehp_link_enable(struct controller *ctrl)
345 {
346 	return __pciehp_link_set(ctrl, true);
347 }
348 
pciehp_get_attention_status(struct slot * slot,u8 * status)349 void pciehp_get_attention_status(struct slot *slot, u8 *status)
350 {
351 	struct controller *ctrl = slot->ctrl;
352 	struct pci_dev *pdev = ctrl_dev(ctrl);
353 	u16 slot_ctrl;
354 
355 	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
356 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x, value read %x\n", __func__,
357 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
358 
359 	switch (slot_ctrl & PCI_EXP_SLTCTL_AIC) {
360 	case PCI_EXP_SLTCTL_ATTN_IND_ON:
361 		*status = 1;	/* On */
362 		break;
363 	case PCI_EXP_SLTCTL_ATTN_IND_BLINK:
364 		*status = 2;	/* Blink */
365 		break;
366 	case PCI_EXP_SLTCTL_ATTN_IND_OFF:
367 		*status = 0;	/* Off */
368 		break;
369 	default:
370 		*status = 0xFF;
371 		break;
372 	}
373 }
374 
pciehp_get_power_status(struct slot * slot,u8 * status)375 void pciehp_get_power_status(struct slot *slot, u8 *status)
376 {
377 	struct controller *ctrl = slot->ctrl;
378 	struct pci_dev *pdev = ctrl_dev(ctrl);
379 	u16 slot_ctrl;
380 
381 	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
382 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x value read %x\n", __func__,
383 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
384 
385 	switch (slot_ctrl & PCI_EXP_SLTCTL_PCC) {
386 	case PCI_EXP_SLTCTL_PWR_ON:
387 		*status = 1;	/* On */
388 		break;
389 	case PCI_EXP_SLTCTL_PWR_OFF:
390 		*status = 0;	/* Off */
391 		break;
392 	default:
393 		*status = 0xFF;
394 		break;
395 	}
396 }
397 
pciehp_get_latch_status(struct slot * slot,u8 * status)398 void pciehp_get_latch_status(struct slot *slot, u8 *status)
399 {
400 	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
401 	u16 slot_status;
402 
403 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
404 	*status = !!(slot_status & PCI_EXP_SLTSTA_MRLSS);
405 }
406 
pciehp_get_adapter_status(struct slot * slot,u8 * status)407 void pciehp_get_adapter_status(struct slot *slot, u8 *status)
408 {
409 	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
410 	u16 slot_status;
411 
412 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
413 	*status = !!(slot_status & PCI_EXP_SLTSTA_PDS);
414 }
415 
pciehp_query_power_fault(struct slot * slot)416 int pciehp_query_power_fault(struct slot *slot)
417 {
418 	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
419 	u16 slot_status;
420 
421 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
422 	return !!(slot_status & PCI_EXP_SLTSTA_PFD);
423 }
424 
pciehp_set_attention_status(struct slot * slot,u8 value)425 void pciehp_set_attention_status(struct slot *slot, u8 value)
426 {
427 	struct controller *ctrl = slot->ctrl;
428 	u16 slot_cmd;
429 
430 	if (!ATTN_LED(ctrl))
431 		return;
432 
433 	switch (value) {
434 	case 0:		/* turn off */
435 		slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_OFF;
436 		break;
437 	case 1:		/* turn on */
438 		slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_ON;
439 		break;
440 	case 2:		/* turn blink */
441 		slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_BLINK;
442 		break;
443 	default:
444 		return;
445 	}
446 	pcie_write_cmd_nowait(ctrl, slot_cmd, PCI_EXP_SLTCTL_AIC);
447 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
448 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
449 }
450 
pciehp_green_led_on(struct slot * slot)451 void pciehp_green_led_on(struct slot *slot)
452 {
453 	struct controller *ctrl = slot->ctrl;
454 
455 	if (!PWR_LED(ctrl))
456 		return;
457 
458 	pcie_write_cmd_nowait(ctrl, PCI_EXP_SLTCTL_PWR_IND_ON,
459 			      PCI_EXP_SLTCTL_PIC);
460 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
461 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
462 		 PCI_EXP_SLTCTL_PWR_IND_ON);
463 }
464 
pciehp_green_led_off(struct slot * slot)465 void pciehp_green_led_off(struct slot *slot)
466 {
467 	struct controller *ctrl = slot->ctrl;
468 
469 	if (!PWR_LED(ctrl))
470 		return;
471 
472 	pcie_write_cmd_nowait(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
473 			      PCI_EXP_SLTCTL_PIC);
474 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
475 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
476 		 PCI_EXP_SLTCTL_PWR_IND_OFF);
477 }
478 
pciehp_green_led_blink(struct slot * slot)479 void pciehp_green_led_blink(struct slot *slot)
480 {
481 	struct controller *ctrl = slot->ctrl;
482 
483 	if (!PWR_LED(ctrl))
484 		return;
485 
486 	pcie_write_cmd_nowait(ctrl, PCI_EXP_SLTCTL_PWR_IND_BLINK,
487 			      PCI_EXP_SLTCTL_PIC);
488 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
489 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
490 		 PCI_EXP_SLTCTL_PWR_IND_BLINK);
491 }
492 
pciehp_power_on_slot(struct slot * slot)493 int pciehp_power_on_slot(struct slot *slot)
494 {
495 	struct controller *ctrl = slot->ctrl;
496 	struct pci_dev *pdev = ctrl_dev(ctrl);
497 	u16 slot_status;
498 	int retval;
499 
500 	/* Clear sticky power-fault bit from previous power failures */
501 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
502 	if (slot_status & PCI_EXP_SLTSTA_PFD)
503 		pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
504 					   PCI_EXP_SLTSTA_PFD);
505 	ctrl->power_fault_detected = 0;
506 
507 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_ON, PCI_EXP_SLTCTL_PCC);
508 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
509 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
510 		 PCI_EXP_SLTCTL_PWR_ON);
511 
512 	retval = pciehp_link_enable(ctrl);
513 	if (retval)
514 		ctrl_err(ctrl, "%s: Can not enable the link!\n", __func__);
515 
516 	return retval;
517 }
518 
pciehp_power_off_slot(struct slot * slot)519 void pciehp_power_off_slot(struct slot *slot)
520 {
521 	struct controller *ctrl = slot->ctrl;
522 
523 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_OFF, PCI_EXP_SLTCTL_PCC);
524 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
525 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
526 		 PCI_EXP_SLTCTL_PWR_OFF);
527 }
528 
pcie_isr(int irq,void * dev_id)529 static irqreturn_t pcie_isr(int irq, void *dev_id)
530 {
531 	struct controller *ctrl = (struct controller *)dev_id;
532 	struct pci_dev *pdev = ctrl_dev(ctrl);
533 	struct pci_bus *subordinate = pdev->subordinate;
534 	struct pci_dev *dev;
535 	struct slot *slot = ctrl->slot;
536 	u16 detected, intr_loc;
537 
538 	/*
539 	 * In order to guarantee that all interrupt events are
540 	 * serviced, we need to re-inspect Slot Status register after
541 	 * clearing what is presumed to be the last pending interrupt.
542 	 */
543 	intr_loc = 0;
544 	do {
545 		pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &detected);
546 
547 		detected &= (PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
548 			     PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC |
549 			     PCI_EXP_SLTSTA_CC | PCI_EXP_SLTSTA_DLLSC);
550 		detected &= ~intr_loc;
551 		intr_loc |= detected;
552 		if (!intr_loc)
553 			return IRQ_NONE;
554 		if (detected)
555 			pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
556 						   intr_loc);
557 	} while (detected);
558 
559 	ctrl_dbg(ctrl, "%s: intr_loc %x\n", __func__, intr_loc);
560 
561 	/* Check Command Complete Interrupt Pending */
562 	if (intr_loc & PCI_EXP_SLTSTA_CC) {
563 		ctrl->cmd_busy = 0;
564 		smp_mb();
565 		wake_up(&ctrl->queue);
566 	}
567 
568 	if (subordinate) {
569 		list_for_each_entry(dev, &subordinate->devices, bus_list) {
570 			if (dev->ignore_hotplug) {
571 				ctrl_dbg(ctrl, "ignoring hotplug event %#06x (%s requested no hotplug)\n",
572 					 intr_loc, pci_name(dev));
573 				return IRQ_HANDLED;
574 			}
575 		}
576 	}
577 
578 	if (!(intr_loc & ~PCI_EXP_SLTSTA_CC))
579 		return IRQ_HANDLED;
580 
581 	/* Check MRL Sensor Changed */
582 	if (intr_loc & PCI_EXP_SLTSTA_MRLSC)
583 		pciehp_handle_switch_change(slot);
584 
585 	/* Check Attention Button Pressed */
586 	if (intr_loc & PCI_EXP_SLTSTA_ABP)
587 		pciehp_handle_attention_button(slot);
588 
589 	/* Check Presence Detect Changed */
590 	if (intr_loc & PCI_EXP_SLTSTA_PDC)
591 		pciehp_handle_presence_change(slot);
592 
593 	/* Check Power Fault Detected */
594 	if ((intr_loc & PCI_EXP_SLTSTA_PFD) && !ctrl->power_fault_detected) {
595 		ctrl->power_fault_detected = 1;
596 		pciehp_handle_power_fault(slot);
597 	}
598 
599 	if (intr_loc & PCI_EXP_SLTSTA_DLLSC)
600 		pciehp_handle_linkstate_change(slot);
601 
602 	return IRQ_HANDLED;
603 }
604 
pcie_enable_notification(struct controller * ctrl)605 void pcie_enable_notification(struct controller *ctrl)
606 {
607 	u16 cmd, mask;
608 
609 	/*
610 	 * TBD: Power fault detected software notification support.
611 	 *
612 	 * Power fault detected software notification is not enabled
613 	 * now, because it caused power fault detected interrupt storm
614 	 * on some machines. On those machines, power fault detected
615 	 * bit in the slot status register was set again immediately
616 	 * when it is cleared in the interrupt service routine, and
617 	 * next power fault detected interrupt was notified again.
618 	 */
619 
620 	/*
621 	 * Always enable link events: thus link-up and link-down shall
622 	 * always be treated as hotplug and unplug respectively. Enable
623 	 * presence detect only if Attention Button is not present.
624 	 */
625 	cmd = PCI_EXP_SLTCTL_DLLSCE;
626 	if (ATTN_BUTTN(ctrl))
627 		cmd |= PCI_EXP_SLTCTL_ABPE;
628 	else
629 		cmd |= PCI_EXP_SLTCTL_PDCE;
630 	if (MRL_SENS(ctrl))
631 		cmd |= PCI_EXP_SLTCTL_MRLSCE;
632 	if (!pciehp_poll_mode)
633 		cmd |= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE;
634 
635 	mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
636 		PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
637 		PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
638 		PCI_EXP_SLTCTL_DLLSCE);
639 
640 	pcie_write_cmd_nowait(ctrl, cmd, mask);
641 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
642 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd);
643 }
644 
pcie_disable_notification(struct controller * ctrl)645 static void pcie_disable_notification(struct controller *ctrl)
646 {
647 	u16 mask;
648 
649 	mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
650 		PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
651 		PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
652 		PCI_EXP_SLTCTL_DLLSCE);
653 	pcie_write_cmd(ctrl, 0, mask);
654 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
655 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0);
656 }
657 
658 /*
659  * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary
660  * bus reset of the bridge, but at the same time we want to ensure that it is
661  * not seen as a hot-unplug, followed by the hot-plug of the device. Thus,
662  * disable link state notification and presence detection change notification
663  * momentarily, if we see that they could interfere. Also, clear any spurious
664  * events after.
665  */
pciehp_reset_slot(struct slot * slot,int probe)666 int pciehp_reset_slot(struct slot *slot, int probe)
667 {
668 	struct controller *ctrl = slot->ctrl;
669 	struct pci_dev *pdev = ctrl_dev(ctrl);
670 	u16 stat_mask = 0, ctrl_mask = 0;
671 
672 	if (probe)
673 		return 0;
674 
675 	if (!ATTN_BUTTN(ctrl)) {
676 		ctrl_mask |= PCI_EXP_SLTCTL_PDCE;
677 		stat_mask |= PCI_EXP_SLTSTA_PDC;
678 	}
679 	ctrl_mask |= PCI_EXP_SLTCTL_DLLSCE;
680 	stat_mask |= PCI_EXP_SLTSTA_DLLSC;
681 
682 	pcie_write_cmd(ctrl, 0, ctrl_mask);
683 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
684 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0);
685 	if (pciehp_poll_mode)
686 		del_timer_sync(&ctrl->poll_timer);
687 
688 	pci_reset_bridge_secondary_bus(ctrl->pcie->port);
689 
690 	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, stat_mask);
691 	pcie_write_cmd_nowait(ctrl, ctrl_mask, ctrl_mask);
692 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
693 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, ctrl_mask);
694 	if (pciehp_poll_mode)
695 		int_poll_timeout(ctrl->poll_timer.data);
696 
697 	return 0;
698 }
699 
pcie_init_notification(struct controller * ctrl)700 int pcie_init_notification(struct controller *ctrl)
701 {
702 	if (pciehp_request_irq(ctrl))
703 		return -1;
704 	pcie_enable_notification(ctrl);
705 	ctrl->notification_enabled = 1;
706 	return 0;
707 }
708 
pcie_shutdown_notification(struct controller * ctrl)709 static void pcie_shutdown_notification(struct controller *ctrl)
710 {
711 	if (ctrl->notification_enabled) {
712 		pcie_disable_notification(ctrl);
713 		pciehp_free_irq(ctrl);
714 		ctrl->notification_enabled = 0;
715 	}
716 }
717 
pcie_init_slot(struct controller * ctrl)718 static int pcie_init_slot(struct controller *ctrl)
719 {
720 	struct slot *slot;
721 
722 	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
723 	if (!slot)
724 		return -ENOMEM;
725 
726 	slot->wq = alloc_workqueue("pciehp-%u", 0, 0, PSN(ctrl));
727 	if (!slot->wq)
728 		goto abort;
729 
730 	slot->ctrl = ctrl;
731 	mutex_init(&slot->lock);
732 	mutex_init(&slot->hotplug_lock);
733 	INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
734 	ctrl->slot = slot;
735 	return 0;
736 abort:
737 	kfree(slot);
738 	return -ENOMEM;
739 }
740 
pcie_cleanup_slot(struct controller * ctrl)741 static void pcie_cleanup_slot(struct controller *ctrl)
742 {
743 	struct slot *slot = ctrl->slot;
744 	cancel_delayed_work(&slot->work);
745 	destroy_workqueue(slot->wq);
746 	kfree(slot);
747 }
748 
dbg_ctrl(struct controller * ctrl)749 static inline void dbg_ctrl(struct controller *ctrl)
750 {
751 	int i;
752 	u16 reg16;
753 	struct pci_dev *pdev = ctrl->pcie->port;
754 
755 	if (!pciehp_debug)
756 		return;
757 
758 	ctrl_info(ctrl, "Hotplug Controller:\n");
759 	ctrl_info(ctrl, "  Seg/Bus/Dev/Func/IRQ : %s IRQ %d\n",
760 		  pci_name(pdev), pdev->irq);
761 	ctrl_info(ctrl, "  Vendor ID            : 0x%04x\n", pdev->vendor);
762 	ctrl_info(ctrl, "  Device ID            : 0x%04x\n", pdev->device);
763 	ctrl_info(ctrl, "  Subsystem ID         : 0x%04x\n",
764 		  pdev->subsystem_device);
765 	ctrl_info(ctrl, "  Subsystem Vendor ID  : 0x%04x\n",
766 		  pdev->subsystem_vendor);
767 	ctrl_info(ctrl, "  PCIe Cap offset      : 0x%02x\n",
768 		  pci_pcie_cap(pdev));
769 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
770 		if (!pci_resource_len(pdev, i))
771 			continue;
772 		ctrl_info(ctrl, "  PCI resource [%d]     : %pR\n",
773 			  i, &pdev->resource[i]);
774 	}
775 	ctrl_info(ctrl, "Slot Capabilities      : 0x%08x\n", ctrl->slot_cap);
776 	ctrl_info(ctrl, "  Physical Slot Number : %d\n", PSN(ctrl));
777 	ctrl_info(ctrl, "  Attention Button     : %3s\n",
778 		  ATTN_BUTTN(ctrl) ? "yes" : "no");
779 	ctrl_info(ctrl, "  Power Controller     : %3s\n",
780 		  POWER_CTRL(ctrl) ? "yes" : "no");
781 	ctrl_info(ctrl, "  MRL Sensor           : %3s\n",
782 		  MRL_SENS(ctrl)   ? "yes" : "no");
783 	ctrl_info(ctrl, "  Attention Indicator  : %3s\n",
784 		  ATTN_LED(ctrl)   ? "yes" : "no");
785 	ctrl_info(ctrl, "  Power Indicator      : %3s\n",
786 		  PWR_LED(ctrl)    ? "yes" : "no");
787 	ctrl_info(ctrl, "  Hot-Plug Surprise    : %3s\n",
788 		  HP_SUPR_RM(ctrl) ? "yes" : "no");
789 	ctrl_info(ctrl, "  EMI Present          : %3s\n",
790 		  EMI(ctrl)        ? "yes" : "no");
791 	ctrl_info(ctrl, "  Command Completed    : %3s\n",
792 		  NO_CMD_CMPL(ctrl) ? "no" : "yes");
793 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &reg16);
794 	ctrl_info(ctrl, "Slot Status            : 0x%04x\n", reg16);
795 	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &reg16);
796 	ctrl_info(ctrl, "Slot Control           : 0x%04x\n", reg16);
797 }
798 
799 #define FLAG(x, y)	(((x) & (y)) ? '+' : '-')
800 
pcie_init(struct pcie_device * dev)801 struct controller *pcie_init(struct pcie_device *dev)
802 {
803 	struct controller *ctrl;
804 	u32 slot_cap, link_cap;
805 	struct pci_dev *pdev = dev->port;
806 
807 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
808 	if (!ctrl) {
809 		dev_err(&dev->device, "%s: Out of memory\n", __func__);
810 		goto abort;
811 	}
812 	ctrl->pcie = dev;
813 	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
814 	ctrl->slot_cap = slot_cap;
815 	mutex_init(&ctrl->ctrl_lock);
816 	init_waitqueue_head(&ctrl->queue);
817 	dbg_ctrl(ctrl);
818 
819 	/* Check if Data Link Layer Link Active Reporting is implemented */
820 	pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
821 	if (link_cap & PCI_EXP_LNKCAP_DLLLARC) {
822 		ctrl_dbg(ctrl, "Link Active Reporting supported\n");
823 		ctrl->link_active_reporting = 1;
824 	}
825 
826 	/* Clear all remaining event bits in Slot Status register */
827 	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
828 		PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
829 		PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC |
830 		PCI_EXP_SLTSTA_CC | PCI_EXP_SLTSTA_DLLSC);
831 
832 	ctrl_info(ctrl, "Slot #%d AttnBtn%c AttnInd%c PwrInd%c PwrCtrl%c MRL%c Interlock%c NoCompl%c LLActRep%c\n",
833 		(slot_cap & PCI_EXP_SLTCAP_PSN) >> 19,
834 		FLAG(slot_cap, PCI_EXP_SLTCAP_ABP),
835 		FLAG(slot_cap, PCI_EXP_SLTCAP_AIP),
836 		FLAG(slot_cap, PCI_EXP_SLTCAP_PIP),
837 		FLAG(slot_cap, PCI_EXP_SLTCAP_PCP),
838 		FLAG(slot_cap, PCI_EXP_SLTCAP_MRLSP),
839 		FLAG(slot_cap, PCI_EXP_SLTCAP_EIP),
840 		FLAG(slot_cap, PCI_EXP_SLTCAP_NCCS),
841 		FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC));
842 
843 	if (pcie_init_slot(ctrl))
844 		goto abort_ctrl;
845 
846 	return ctrl;
847 
848 abort_ctrl:
849 	kfree(ctrl);
850 abort:
851 	return NULL;
852 }
853 
pciehp_release_ctrl(struct controller * ctrl)854 void pciehp_release_ctrl(struct controller *ctrl)
855 {
856 	pcie_shutdown_notification(ctrl);
857 	pcie_cleanup_slot(ctrl);
858 	kfree(ctrl);
859 }
860