shpchp_ctrl.c

  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Standard Hot Plug Controller 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/module.h>
 17#include <linux/kernel.h>
 18#include <linux/types.h>
 19#include <linux/slab.h>
 20#include <linux/pci.h>
 21#include "../pci.h"
 22#include "shpchp.h"
 23
 24static void interrupt_event_handler(struct work_struct *work);
 25static int shpchp_enable_slot(struct slot *p_slot);
 26static int shpchp_disable_slot(struct slot *p_slot);
 27
 28static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
 29{
 30	struct event_info *info;
 31
 32	info = kmalloc(sizeof(*info), GFP_ATOMIC);
 33	if (!info)
 34		return -ENOMEM;
 35
 36	info->event_type = event_type;
 37	info->p_slot = p_slot;
 38	INIT_WORK(&info->work, interrupt_event_handler);
 39
 40	queue_work(p_slot->wq, &info->work);
 41
 42	return 0;
 43}
 44
 45u8 shpchp_handle_attention_button(u8 hp_slot, struct controller *ctrl)
 46{
 47	struct slot *p_slot;
 48	u32 event_type;
 49
 50	/* Attention Button Change */
 51	ctrl_dbg(ctrl, "Attention button interrupt received\n");
 52
 53	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
 54	shpchp_get_adapter_status(p_slot, &p_slot->presence_save);
 55
 56	/*
 57	 *  Button pressed - See if need to TAKE ACTION!!!
 58	 */
 59	ctrl_info(ctrl, "Button pressed on Slot(%s)\n", slot_name(p_slot));
 60	event_type = INT_BUTTON_PRESS;
 61
 62	queue_interrupt_event(p_slot, event_type);
 63
 64	return 0;
 65
 66}
 67
 68u8 shpchp_handle_switch_change(u8 hp_slot, struct controller *ctrl)
 69{
 70	struct slot *p_slot;
 71	u8 getstatus;
 72	u32 event_type;
 73
 74	/* Switch Change */
 75	ctrl_dbg(ctrl, "Switch interrupt received\n");
 76
 77	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
 78	shpchp_get_adapter_status(p_slot, &p_slot->presence_save);
 79	shpchp_get_latch_status(p_slot, &getstatus);
 80	ctrl_dbg(ctrl, "Card present %x Power status %x\n",
 81		 p_slot->presence_save, p_slot->pwr_save);
 82
 83	if (getstatus) {
 84		/*
 85		 * Switch opened
 86		 */
 87		ctrl_info(ctrl, "Latch open on Slot(%s)\n", slot_name(p_slot));
 88		event_type = INT_SWITCH_OPEN;
 89		if (p_slot->pwr_save && p_slot->presence_save) {
 90			event_type = INT_POWER_FAULT;
 91			ctrl_err(ctrl, "Surprise Removal of card\n");
 92		}
 93	} else {
 94		/*
 95		 *  Switch closed
 96		 */
 97		ctrl_info(ctrl, "Latch close on Slot(%s)\n", slot_name(p_slot));
 98		event_type = INT_SWITCH_CLOSE;
 99	}
100
101	queue_interrupt_event(p_slot, event_type);
102
103	return 1;
104}
105
106u8 shpchp_handle_presence_change(u8 hp_slot, struct controller *ctrl)
107{
108	struct slot *p_slot;
109	u32 event_type;
110
111	/* Presence Change */
112	ctrl_dbg(ctrl, "Presence/Notify input change\n");
113
114	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
115
116	/*
117	 * Save the presence state
118	 */
119	shpchp_get_adapter_status(p_slot, &p_slot->presence_save);
120	if (p_slot->presence_save) {
121		/*
122		 * Card Present
123		 */
124		ctrl_info(ctrl, "Card present on Slot(%s)\n",
125			  slot_name(p_slot));
126		event_type = INT_PRESENCE_ON;
127	} else {
128		/*
129		 * Not Present
130		 */
131		ctrl_info(ctrl, "Card not present on Slot(%s)\n",
132			  slot_name(p_slot));
133		event_type = INT_PRESENCE_OFF;
134	}
135
136	queue_interrupt_event(p_slot, event_type);
137
138	return 1;
139}
140
141u8 shpchp_handle_power_fault(u8 hp_slot, struct controller *ctrl)
142{
143	struct slot *p_slot;
144	u32 event_type;
145
146	/* Power fault */
147	ctrl_dbg(ctrl, "Power fault interrupt received\n");
148
149	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
150
151	if (!(shpchp_query_power_fault(p_slot))) {
152		/*
153		 * Power fault Cleared
154		 */
155		ctrl_info(ctrl, "Power fault cleared on Slot(%s)\n",
156			  slot_name(p_slot));
157		p_slot->status = 0x00;
158		event_type = INT_POWER_FAULT_CLEAR;
159	} else {
160		/*
161		 *   Power fault
162		 */
163		ctrl_info(ctrl, "Power fault on Slot(%s)\n", slot_name(p_slot));
164		event_type = INT_POWER_FAULT;
165		/* set power fault status for this board */
166		p_slot->status = 0xFF;
167		ctrl_info(ctrl, "Power fault bit %x set\n", hp_slot);
168	}
169
170	queue_interrupt_event(p_slot, event_type);
171
172	return 1;
173}
174
175/* The following routines constitute the bulk of the
176   hotplug controller logic
177 */
178static int change_bus_speed(struct controller *ctrl, struct slot *p_slot,
179		enum pci_bus_speed speed)
180{
181	int rc = 0;
182
183	ctrl_dbg(ctrl, "Change speed to %d\n", speed);
184	rc = shpchp_set_bus_speed_mode(p_slot, speed);
185	if (rc) {
186		ctrl_err(ctrl, "%s: Issue of set bus speed mode command failed\n",
187			 __func__);
188		return WRONG_BUS_FREQUENCY;
189	}
190	return rc;
191}
192
193static int fix_bus_speed(struct controller *ctrl, struct slot *pslot,
194		u8 flag, enum pci_bus_speed asp, enum pci_bus_speed bsp,
195		enum pci_bus_speed msp)
196{
197	int rc = 0;
198
199	/*
200	 * If other slots on the same bus are occupied, we cannot
201	 * change the bus speed.
202	 */
203	if (flag) {
204		if (asp < bsp) {
205			ctrl_err(ctrl, "Speed of bus %x and adapter %x mismatch\n",
206				 bsp, asp);
207			rc = WRONG_BUS_FREQUENCY;
208		}
209		return rc;
210	}
211
212	if (asp < msp) {
213		if (bsp != asp)
214			rc = change_bus_speed(ctrl, pslot, asp);
215	} else {
216		if (bsp != msp)
217			rc = change_bus_speed(ctrl, pslot, msp);
218	}
219	return rc;
220}
221
222/**
223 * board_added - Called after a board has been added to the system.
224 * @p_slot: target &slot
225 *
226 * Turns power on for the board.
227 * Configures board.
228 */
229static int board_added(struct slot *p_slot)
230{
231	u8 hp_slot;
232	u8 slots_not_empty = 0;
233	int rc = 0;
234	enum pci_bus_speed asp, bsp, msp;
235	struct controller *ctrl = p_slot->ctrl;
236	struct pci_bus *parent = ctrl->pci_dev->subordinate;
237
238	hp_slot = p_slot->device - ctrl->slot_device_offset;
239
240	ctrl_dbg(ctrl, "%s: p_slot->device, slot_offset, hp_slot = %d, %d ,%d\n",
241		 __func__, p_slot->device, ctrl->slot_device_offset, hp_slot);
242
243	/* Power on slot without connecting to bus */
244	rc = shpchp_power_on_slot(p_slot);
245	if (rc) {
246		ctrl_err(ctrl, "Failed to power on slot\n");
247		return -1;
248	}
249
250	if ((ctrl->pci_dev->vendor == 0x8086) && (ctrl->pci_dev->device == 0x0332)) {
251		rc = shpchp_set_bus_speed_mode(p_slot, PCI_SPEED_33MHz);
252		if (rc) {
253			ctrl_err(ctrl, "%s: Issue of set bus speed mode command failed\n",
254				 __func__);
255			return WRONG_BUS_FREQUENCY;
256		}
257
258		/* turn on board, blink green LED, turn off Amber LED */
259		rc = shpchp_slot_enable(p_slot);
260		if (rc) {
261			ctrl_err(ctrl, "Issue of Slot Enable command failed\n");
262			return rc;
263		}
264	}
265
266	rc = shpchp_get_adapter_speed(p_slot, &asp);
267	if (rc) {
268		ctrl_err(ctrl, "Can't get adapter speed or bus mode mismatch\n");
269		return WRONG_BUS_FREQUENCY;
270	}
271
272	bsp = ctrl->pci_dev->subordinate->cur_bus_speed;
273	msp = ctrl->pci_dev->subordinate->max_bus_speed;
274
275	/* Check if there are other slots or devices on the same bus */
276	if (!list_empty(&ctrl->pci_dev->subordinate->devices))
277		slots_not_empty = 1;
278
279	ctrl_dbg(ctrl, "%s: slots_not_empty %d, adapter_speed %d, bus_speed %d, max_bus_speed %d\n",
280		 __func__, slots_not_empty, asp,
281		 bsp, msp);
282
283	rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, asp, bsp, msp);
284	if (rc)
285		return rc;
286
287	/* turn on board, blink green LED, turn off Amber LED */
288	rc = shpchp_slot_enable(p_slot);
289	if (rc) {
290		ctrl_err(ctrl, "Issue of Slot Enable command failed\n");
291		return rc;
292	}
293
294	/* Wait for ~1 second */
295	msleep(1000);
296
297	ctrl_dbg(ctrl, "%s: slot status = %x\n", __func__, p_slot->status);
298	/* Check for a power fault */
299	if (p_slot->status == 0xFF) {
300		/* power fault occurred, but it was benign */
301		ctrl_dbg(ctrl, "%s: Power fault\n", __func__);
302		p_slot->status = 0;
303		goto err_exit;
304	}
305
306	if (shpchp_configure_device(p_slot)) {
307		ctrl_err(ctrl, "Cannot add device at %04x:%02x:%02x\n",
308			 pci_domain_nr(parent), p_slot->bus, p_slot->device);
309		goto err_exit;
310	}
311
312	p_slot->status = 0;
313	p_slot->is_a_board = 0x01;
314	p_slot->pwr_save = 1;
315
316	shpchp_green_led_on(p_slot);
317
318	return 0;
319
320err_exit:
321	/* turn off slot, turn on Amber LED, turn off Green LED */
322	rc = shpchp_slot_disable(p_slot);
323	if (rc) {
324		ctrl_err(ctrl, "%s: Issue of Slot Disable command failed\n",
325			 __func__);
326		return rc;
327	}
328
329	return(rc);
330}
331
332
333/**
334 * remove_board - Turns off slot and LEDs
335 * @p_slot: target &slot
336 */
337static int remove_board(struct slot *p_slot)
338{
339	struct controller *ctrl = p_slot->ctrl;
340	u8 hp_slot;
341	int rc;
342
343	shpchp_unconfigure_device(p_slot);
344
345	hp_slot = p_slot->device - ctrl->slot_device_offset;
346	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
347
348	ctrl_dbg(ctrl, "%s: hp_slot = %d\n", __func__, hp_slot);
349
350	/* Change status to shutdown */
351	if (p_slot->is_a_board)
352		p_slot->status = 0x01;
353
354	/* turn off slot, turn on Amber LED, turn off Green LED */
355	rc = shpchp_slot_disable(p_slot);
356	if (rc) {
357		ctrl_err(ctrl, "%s: Issue of Slot Disable command failed\n",
358			 __func__);
359		return rc;
360	}
361
362	rc = shpchp_set_attention_status(p_slot, 0);
363	if (rc) {
364		ctrl_err(ctrl, "Issue of Set Attention command failed\n");
365		return rc;
366	}
367
368	p_slot->pwr_save = 0;
369	p_slot->is_a_board = 0;
370
371	return 0;
372}
373
374
375struct pushbutton_work_info {
376	struct slot *p_slot;
377	struct work_struct work;
378};
379
380/**
381 * shpchp_pushbutton_thread - handle pushbutton events
382 * @work: &struct work_struct to be handled
383 *
384 * Scheduled procedure to handle blocking stuff for the pushbuttons.
385 * Handles all pending events and exits.
386 */
387static void shpchp_pushbutton_thread(struct work_struct *work)
388{
389	struct pushbutton_work_info *info =
390		container_of(work, struct pushbutton_work_info, work);
391	struct slot *p_slot = info->p_slot;
392
393	mutex_lock(&p_slot->lock);
394	switch (p_slot->state) {
395	case POWEROFF_STATE:
396		mutex_unlock(&p_slot->lock);
397		shpchp_disable_slot(p_slot);
398		mutex_lock(&p_slot->lock);
399		p_slot->state = STATIC_STATE;
400		break;
401	case POWERON_STATE:
402		mutex_unlock(&p_slot->lock);
403		if (shpchp_enable_slot(p_slot))
404			shpchp_green_led_off(p_slot);
405		mutex_lock(&p_slot->lock);
406		p_slot->state = STATIC_STATE;
407		break;
408	default:
409		break;
410	}
411	mutex_unlock(&p_slot->lock);
412
413	kfree(info);
414}
415
416void shpchp_queue_pushbutton_work(struct work_struct *work)
417{
418	struct slot *p_slot = container_of(work, struct slot, work.work);
419	struct pushbutton_work_info *info;
420
421	info = kmalloc(sizeof(*info), GFP_KERNEL);
422	if (!info) {
423		ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
424			 __func__);
425		return;
426	}
427	info->p_slot = p_slot;
428	INIT_WORK(&info->work, shpchp_pushbutton_thread);
429
430	mutex_lock(&p_slot->lock);
431	switch (p_slot->state) {
432	case BLINKINGOFF_STATE:
433		p_slot->state = POWEROFF_STATE;
434		break;
435	case BLINKINGON_STATE:
436		p_slot->state = POWERON_STATE;
437		break;
438	default:
439		kfree(info);
440		goto out;
441	}
442	queue_work(p_slot->wq, &info->work);
443 out:
444	mutex_unlock(&p_slot->lock);
445}
446
447static void update_slot_info(struct slot *slot)
448{
449	shpchp_get_power_status(slot, &slot->pwr_save);
450	shpchp_get_attention_status(slot, &slot->attention_save);
451	shpchp_get_latch_status(slot, &slot->latch_save);
452	shpchp_get_adapter_status(slot, &slot->presence_save);
453}
454
455/*
456 * Note: This function must be called with slot->lock held
457 */
458static void handle_button_press_event(struct slot *p_slot)
459{
460	u8 getstatus;
461	struct controller *ctrl = p_slot->ctrl;
462
463	switch (p_slot->state) {
464	case STATIC_STATE:
465		shpchp_get_power_status(p_slot, &getstatus);
466		if (getstatus) {
467			p_slot->state = BLINKINGOFF_STATE;
468			ctrl_info(ctrl, "PCI slot #%s - powering off due to button press\n",
469				  slot_name(p_slot));
470		} else {
471			p_slot->state = BLINKINGON_STATE;
472			ctrl_info(ctrl, "PCI slot #%s - powering on due to button press\n",
473				  slot_name(p_slot));
474		}
475		/* blink green LED and turn off amber */
476		shpchp_green_led_blink(p_slot);
477		shpchp_set_attention_status(p_slot, 0);
478
479		queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
480		break;
481	case BLINKINGOFF_STATE:
482	case BLINKINGON_STATE:
483		/*
484		 * Cancel if we are still blinking; this means that we
485		 * press the attention again before the 5 sec. limit
486		 * expires to cancel hot-add or hot-remove
487		 */
488		ctrl_info(ctrl, "Button cancel on Slot(%s)\n",
489			  slot_name(p_slot));
490		cancel_delayed_work(&p_slot->work);
491		if (p_slot->state == BLINKINGOFF_STATE)
492			shpchp_green_led_on(p_slot);
493		else
494			shpchp_green_led_off(p_slot);
495		shpchp_set_attention_status(p_slot, 0);
496		ctrl_info(ctrl, "PCI slot #%s - action canceled due to button press\n",
497			  slot_name(p_slot));
498		p_slot->state = STATIC_STATE;
499		break;
500	case POWEROFF_STATE:
501	case POWERON_STATE:
502		/*
503		 * Ignore if the slot is on power-on or power-off state;
504		 * this means that the previous attention button action
505		 * to hot-add or hot-remove is undergoing
506		 */
507		ctrl_info(ctrl, "Button ignore on Slot(%s)\n",
508			  slot_name(p_slot));
509		update_slot_info(p_slot);
510		break;
511	default:
512		ctrl_warn(ctrl, "Not a valid state\n");
513		break;
514	}
515}
516
517static void interrupt_event_handler(struct work_struct *work)
518{
519	struct event_info *info = container_of(work, struct event_info, work);
520	struct slot *p_slot = info->p_slot;
521
522	mutex_lock(&p_slot->lock);
523	switch (info->event_type) {
524	case INT_BUTTON_PRESS:
525		handle_button_press_event(p_slot);
526		break;
527	case INT_POWER_FAULT:
528		ctrl_dbg(p_slot->ctrl, "%s: Power fault\n", __func__);
529		shpchp_set_attention_status(p_slot, 1);
530		shpchp_green_led_off(p_slot);
531		break;
532	default:
533		update_slot_info(p_slot);
534		break;
535	}
536	mutex_unlock(&p_slot->lock);
537
538	kfree(info);
539}
540
541
542static int shpchp_enable_slot (struct slot *p_slot)
543{
544	u8 getstatus = 0;
545	int rc, retval = -ENODEV;
546	struct controller *ctrl = p_slot->ctrl;
547
548	/* Check to see if (latch closed, card present, power off) */
549	mutex_lock(&p_slot->ctrl->crit_sect);
550	rc = shpchp_get_adapter_status(p_slot, &getstatus);
551	if (rc || !getstatus) {
552		ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
553		goto out;
554	}
555	rc = shpchp_get_latch_status(p_slot, &getstatus);
556	if (rc || getstatus) {
557		ctrl_info(ctrl, "Latch open on slot(%s)\n", slot_name(p_slot));
558		goto out;
559	}
560	rc = shpchp_get_power_status(p_slot, &getstatus);
561	if (rc || getstatus) {
562		ctrl_info(ctrl, "Already enabled on slot(%s)\n",
563			  slot_name(p_slot));
564		goto out;
565	}
566
567	p_slot->is_a_board = 1;
568
569	/* We have to save the presence info for these slots */
570	shpchp_get_adapter_status(p_slot, &p_slot->presence_save);
571	shpchp_get_power_status(p_slot, &p_slot->pwr_save);
572	ctrl_dbg(ctrl, "%s: p_slot->pwr_save %x\n", __func__, p_slot->pwr_save);
573	shpchp_get_latch_status(p_slot, &getstatus);
574
575	if ((p_slot->ctrl->pci_dev->vendor == PCI_VENDOR_ID_AMD &&
576	     p_slot->ctrl->pci_dev->device == PCI_DEVICE_ID_AMD_POGO_7458)
577	     && p_slot->ctrl->num_slots == 1) {
578		/* handle AMD POGO errata; this must be done before enable  */
579		amd_pogo_errata_save_misc_reg(p_slot);
580		retval = board_added(p_slot);
581		/* handle AMD POGO errata; this must be done after enable  */
582		amd_pogo_errata_restore_misc_reg(p_slot);
583	} else
584		retval = board_added(p_slot);
585
586	if (retval) {
587		shpchp_get_adapter_status(p_slot, &p_slot->presence_save);
588		shpchp_get_latch_status(p_slot, &getstatus);
589	}
590
591	update_slot_info(p_slot);
592 out:
593	mutex_unlock(&p_slot->ctrl->crit_sect);
594	return retval;
595}
596
597
598static int shpchp_disable_slot (struct slot *p_slot)
599{
600	u8 getstatus = 0;
601	int rc, retval = -ENODEV;
602	struct controller *ctrl = p_slot->ctrl;
603
604	if (!p_slot->ctrl)
605		return -ENODEV;
606
607	/* Check to see if (latch closed, card present, power on) */
608	mutex_lock(&p_slot->ctrl->crit_sect);
609
610	rc = shpchp_get_adapter_status(p_slot, &getstatus);
611	if (rc || !getstatus) {
612		ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
613		goto out;
614	}
615	rc = shpchp_get_latch_status(p_slot, &getstatus);
616	if (rc || getstatus) {
617		ctrl_info(ctrl, "Latch open on slot(%s)\n", slot_name(p_slot));
618		goto out;
619	}
620	rc = shpchp_get_power_status(p_slot, &getstatus);
621	if (rc || !getstatus) {
622		ctrl_info(ctrl, "Already disabled on slot(%s)\n",
623			  slot_name(p_slot));
624		goto out;
625	}
626
627	retval = remove_board(p_slot);
628	update_slot_info(p_slot);
629 out:
630	mutex_unlock(&p_slot->ctrl->crit_sect);
631	return retval;
632}
633
634int shpchp_sysfs_enable_slot(struct slot *p_slot)
635{
636	int retval = -ENODEV;
637	struct controller *ctrl = p_slot->ctrl;
638
639	mutex_lock(&p_slot->lock);
640	switch (p_slot->state) {
641	case BLINKINGON_STATE:
642		cancel_delayed_work(&p_slot->work);
643		fallthrough;
644	case STATIC_STATE:
645		p_slot->state = POWERON_STATE;
646		mutex_unlock(&p_slot->lock);
647		retval = shpchp_enable_slot(p_slot);
648		mutex_lock(&p_slot->lock);
649		p_slot->state = STATIC_STATE;
650		break;
651	case POWERON_STATE:
652		ctrl_info(ctrl, "Slot %s is already in powering on state\n",
653			  slot_name(p_slot));
654		break;
655	case BLINKINGOFF_STATE:
656	case POWEROFF_STATE:
657		ctrl_info(ctrl, "Already enabled on slot %s\n",
658			  slot_name(p_slot));
659		break;
660	default:
661		ctrl_err(ctrl, "Not a valid state on slot %s\n",
662			 slot_name(p_slot));
663		break;
664	}
665	mutex_unlock(&p_slot->lock);
666
667	return retval;
668}
669
670int shpchp_sysfs_disable_slot(struct slot *p_slot)
671{
672	int retval = -ENODEV;
673	struct controller *ctrl = p_slot->ctrl;
674
675	mutex_lock(&p_slot->lock);
676	switch (p_slot->state) {
677	case BLINKINGOFF_STATE:
678		cancel_delayed_work(&p_slot->work);
679		fallthrough;
680	case STATIC_STATE:
681		p_slot->state = POWEROFF_STATE;
682		mutex_unlock(&p_slot->lock);
683		retval = shpchp_disable_slot(p_slot);
684		mutex_lock(&p_slot->lock);
685		p_slot->state = STATIC_STATE;
686		break;
687	case POWEROFF_STATE:
688		ctrl_info(ctrl, "Slot %s is already in powering off state\n",
689			  slot_name(p_slot));
690		break;
691	case BLINKINGON_STATE:
692	case POWERON_STATE:
693		ctrl_info(ctrl, "Already disabled on slot %s\n",
694			  slot_name(p_slot));
695		break;
696	default:
697		ctrl_err(ctrl, "Not a valid state on slot %s\n",
698			 slot_name(p_slot));
699		break;
700	}
701	mutex_unlock(&p_slot->lock);
702
703	return retval;
704}