summaryrefslogtreecommitdiffstats
path: root/drivers/pci/hotplug/pciehp_core.c
blob: ad3393930ecb4d91dc21ef7a5abf575662c76e7c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
// SPDX-License-Identifier: GPL-2.0+
/*
 * PCI Express Hot Plug Controller Driver
 *
 * Copyright (C) 1995,2001 Compaq Computer Corporation
 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
 * Copyright (C) 2001 IBM Corp.
 * Copyright (C) 2003-2004 Intel Corporation
 *
 * All rights reserved.
 *
 * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
 *
 * Authors:
 *   Dan Zink <dan.zink@compaq.com>
 *   Greg Kroah-Hartman <greg@kroah.com>
 *   Dely Sy <dely.l.sy@intel.com>"
 */

#define pr_fmt(fmt) "pciehp: " fmt
#define dev_fmt pr_fmt

#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/pci.h>
#include "pciehp.h"

#include "../pci.h"

/* Global variables */
bool pciehp_poll_mode;
int pciehp_poll_time;

/*
 * not really modular, but the easiest way to keep compat with existing
 * bootargs behaviour is to continue using module_param here.
 */
module_param(pciehp_poll_mode, bool, 0644);
module_param(pciehp_poll_time, int, 0644);
MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");

static int set_attention_status(struct hotplug_slot *slot, u8 value);
static int get_power_status(struct hotplug_slot *slot, u8 *value);
static int get_latch_status(struct hotplug_slot *slot, u8 *value);
static int get_adapter_status(struct hotplug_slot *slot, u8 *value);

static int init_slot(struct controller *ctrl)
{
	struct hotplug_slot_ops *ops;
	char name[SLOT_NAME_SIZE];
	int retval;

	/* Setup hotplug slot ops */
	ops = kzalloc(sizeof(*ops), GFP_KERNEL);
	if (!ops)
		return -ENOMEM;

	ops->enable_slot = pciehp_sysfs_enable_slot;
	ops->disable_slot = pciehp_sysfs_disable_slot;
	ops->get_power_status = get_power_status;
	ops->get_adapter_status = get_adapter_status;
	ops->reset_slot = pciehp_reset_slot;
	if (MRL_SENS(ctrl))
		ops->get_latch_status = get_latch_status;
	if (ATTN_LED(ctrl)) {
		ops->get_attention_status = pciehp_get_attention_status;
		ops->set_attention_status = set_attention_status;
	} else if (ctrl->pcie->port->hotplug_user_indicators) {
		ops->get_attention_status = pciehp_get_raw_indicator_status;
		ops->set_attention_status = pciehp_set_raw_indicator_status;
	}

	/* register this slot with the hotplug pci core */
	ctrl->hotplug_slot.ops = ops;
	snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));

	retval = pci_hp_initialize(&ctrl->hotplug_slot,
				   ctrl->pcie->port->subordinate, 0, name);
	if (retval) {
		ctrl_err(ctrl, "pci_hp_initialize failed: error %d\n", retval);
		kfree(ops);
	}
	return retval;
}

static void cleanup_slot(struct controller *ctrl)
{
	struct hotplug_slot *hotplug_slot = &ctrl->hotplug_slot;

	pci_hp_destroy(hotplug_slot);
	kfree(hotplug_slot->ops);
}

/*
 * set_attention_status - Turns the Attention Indicator on, off or blinking
 */
static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
{
	struct controller *ctrl = to_ctrl(hotplug_slot);
	struct pci_dev *pdev = ctrl->pcie->port;

	if (status)
		status <<= PCI_EXP_SLTCTL_ATTN_IND_SHIFT;
	else
		status = PCI_EXP_SLTCTL_ATTN_IND_OFF;

	pci_config_pm_runtime_get(pdev);
	pciehp_set_indicators(ctrl, INDICATOR_NOOP, status);
	pci_config_pm_runtime_put(pdev);
	return 0;
}

static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
	struct controller *ctrl = to_ctrl(hotplug_slot);
	struct pci_dev *pdev = ctrl->pcie->port;

	pci_config_pm_runtime_get(pdev);
	pciehp_get_power_status(ctrl, value);
	pci_config_pm_runtime_put(pdev);
	return 0;
}

static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
	struct controller *ctrl = to_ctrl(hotplug_slot);
	struct pci_dev *pdev = ctrl->pcie->port;

	pci_config_pm_runtime_get(pdev);
	pciehp_get_latch_status(ctrl, value);
	pci_config_pm_runtime_put(pdev);
	return 0;
}

static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
{
	struct controller *ctrl = to_ctrl(hotplug_slot);
	struct pci_dev *pdev = ctrl->pcie->port;
	int ret;

	pci_config_pm_runtime_get(pdev);
	ret = pciehp_card_present_or_link_active(ctrl);
	pci_config_pm_runtime_put(pdev);
	if (ret < 0)
		return ret;

	*value = ret;
	return 0;
}

/**
 * pciehp_check_presence() - synthesize event if presence has changed
 * @ctrl: controller to check
 *
 * On probe and resume, an explicit presence check is necessary to bring up an
 * occupied slot or bring down an unoccupied slot.  This can't be triggered by
 * events in the Slot Status register, they may be stale and are therefore
 * cleared.  Secondly, sending an interrupt for "events that occur while
 * interrupt generation is disabled [when] interrupt generation is subsequently
 * enabled" is optional per PCIe r4.0, sec 6.7.3.4.
 */
static void pciehp_check_presence(struct controller *ctrl)
{
	int occupied;

	down_read(&ctrl->reset_lock);
	mutex_lock(&ctrl->state_lock);

	occupied = pciehp_card_present_or_link_active(ctrl);
	if ((occupied > 0 && (ctrl->state == OFF_STATE ||
			  ctrl->state == BLINKINGON_STATE)) ||
	    (!occupied && (ctrl->state == ON_STATE ||
			   ctrl->state == BLINKINGOFF_STATE)))
		pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);

	mutex_unlock(&ctrl->state_lock);
	up_read(&ctrl->reset_lock);
}

static int pciehp_probe(struct pcie_device *dev)
{
	int rc;
	struct controller *ctrl;

	/* If this is not a "hotplug" service, we have no business here. */
	if (dev->service != PCIE_PORT_SERVICE_HP)
		return -ENODEV;

	if (!dev->port->subordinate) {
		/* Can happen if we run out of bus numbers during probe */
		pci_err(dev->port,
			"Hotplug bridge without secondary bus, ignoring\n");
		return -ENODEV;
	}

	ctrl = pcie_init(dev);
	if (!ctrl) {
		pci_err(dev->port, "Controller initialization failed\n");
		return -ENODEV;
	}
	set_service_data(dev, ctrl);

	/* Setup the slot information structures */
	rc = init_slot(ctrl);
	if (rc) {
		if (rc == -EBUSY)
			ctrl_warn(ctrl, "Slot already registered by another hotplug driver\n");
		else
			ctrl_err(ctrl, "Slot initialization failed (%d)\n", rc);
		goto err_out_release_ctlr;
	}

	/* Enable events after we have setup the data structures */
	rc = pcie_init_notification(ctrl);
	if (rc) {
		ctrl_err(ctrl, "Notification initialization failed (%d)\n", rc);
		goto err_out_free_ctrl_slot;
	}

	/* Publish to user space */
	rc = pci_hp_add(&ctrl->hotplug_slot);
	if (rc) {
		ctrl_err(ctrl, "Publication to user space failed (%d)\n", rc);
		goto err_out_shutdown_notification;
	}

	pciehp_check_presence(ctrl);

	return 0;

err_out_shutdown_notification:
	pcie_shutdown_notification(ctrl);
err_out_free_ctrl_slot:
	cleanup_slot(ctrl);
err_out_release_ctlr:
	pciehp_release_ctrl(ctrl);
	return -ENODEV;
}

static void pciehp_remove(struct pcie_device *dev)
{
	struct controller *ctrl = get_service_data(dev);

	pci_hp_del(&ctrl->hotplug_slot);
	pcie_shutdown_notification(ctrl);
	cleanup_slot(ctrl);
	pciehp_release_ctrl(ctrl);
}

#ifdef CONFIG_PM
static bool pme_is_native(struct pcie_device *dev)
{
	const struct pci_host_bridge *host;

	host = pci_find_host_bridge(dev->port->bus);
	return pcie_ports_native || host->native_pme;
}

static void pciehp_disable_interrupt(struct pcie_device *dev)
{
	/*
	 * Disable hotplug interrupt so that it does not trigger
	 * immediately when the downstream link goes down.
	 */
	if (pme_is_native(dev))
		pcie_disable_interrupt(get_service_data(dev));
}

#ifdef CONFIG_PM_SLEEP
static int pciehp_suspend(struct pcie_device *dev)
{
	/*
	 * If the port is already runtime suspended we can keep it that
	 * way.
	 */
	if (dev_pm_skip_suspend(&dev->port->dev))
		return 0;

	pciehp_disable_interrupt(dev);
	return 0;
}

static int pciehp_resume_noirq(struct pcie_device *dev)
{
	struct controller *ctrl = get_service_data(dev);

	/* pci_restore_state() just wrote to the Slot Control register */
	ctrl->cmd_started = jiffies;
	ctrl->cmd_busy = true;

	/* clear spurious events from rediscovery of inserted card */
	if (ctrl->state == ON_STATE || ctrl->state == BLINKINGOFF_STATE)
		pcie_clear_hotplug_events(ctrl);

	return 0;
}
#endif

static int pciehp_resume(struct pcie_device *dev)
{
	struct controller *ctrl = get_service_data(dev);

	if (pme_is_native(dev))
		pcie_enable_interrupt(ctrl);

	pciehp_check_presence(ctrl);

	return 0;
}

static int pciehp_runtime_suspend(struct pcie_device *dev)
{
	pciehp_disable_interrupt(dev);
	return 0;
}

static int pciehp_runtime_resume(struct pcie_device *dev)
{
	struct controller *ctrl = get_service_data(dev);

	/* pci_restore_state() just wrote to the Slot Control register */
	ctrl->cmd_started = jiffies;
	ctrl->cmd_busy = true;

	/* clear spurious events from rediscovery of inserted card */
	if ((ctrl->state == ON_STATE || ctrl->state == BLINKINGOFF_STATE) &&
	     pme_is_native(dev))
		pcie_clear_hotplug_events(ctrl);

	return pciehp_resume(dev);
}
#endif /* PM */

static struct pcie_port_service_driver hpdriver_portdrv = {
	.name		= "pciehp",
	.port_type	= PCIE_ANY_PORT,
	.service	= PCIE_PORT_SERVICE_HP,

	.probe		= pciehp_probe,
	.remove		= pciehp_remove,

#ifdef	CONFIG_PM
#ifdef	CONFIG_PM_SLEEP
	.suspend	= pciehp_suspend,
	.resume_noirq	= pciehp_resume_noirq,
	.resume		= pciehp_resume,
#endif
	.runtime_suspend = pciehp_runtime_suspend,
	.runtime_resume	= pciehp_runtime_resume,
#endif	/* PM */
};

int __init pcie_hp_init(void)
{
	int retval = 0;

	retval = pcie_port_service_register(&hpdriver_portdrv);
	pr_debug("pcie_port_service_register = %d\n", retval);
	if (retval)
		pr_debug("Failure to register service\n");

	return retval;
}