aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/misc/mic/card/mic_device.c
blob: 4125217579afabf37dc83f1bb34ae0bdb05e99aa (plain) (blame)
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
/*
 * Intel MIC Platform Software Stack (MPSS)
 *
 * Copyright(c) 2013 Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * The full GNU General Public License is included in this distribution in
 * the file called "COPYING".
 *
 * Disclaimer: The codes contained in these modules may be specific to
 * the Intel Software Development Platform codenamed: Knights Ferry, and
 * the Intel product codenamed: Knights Corner, and are not backward
 * compatible with other Intel products. Additionally, Intel will NOT
 * support the codes or instruction set in future products.
 *
 * Intel MIC Card driver.
 *
 */
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>

#include <linux/mic_common.h>
#include "../common/mic_device.h"
#include "mic_device.h"
#include "mic_virtio.h"

static struct mic_driver *g_drv;
static struct mic_irq *shutdown_cookie;

static void mic_notify_host(u8 state)
{
	struct mic_driver *mdrv = g_drv;
	struct mic_bootparam __iomem *bootparam = mdrv->dp;

	iowrite8(state, &bootparam->shutdown_status);
	dev_dbg(mdrv->dev, "%s %d system_state %d\n",
		__func__, __LINE__, state);
	mic_send_intr(&mdrv->mdev, ioread8(&bootparam->c2h_shutdown_db));
}

static int mic_panic_event(struct notifier_block *this, unsigned long event,
		void *ptr)
{
	struct mic_driver *mdrv = g_drv;
	struct mic_bootparam __iomem *bootparam = mdrv->dp;

	iowrite8(-1, &bootparam->h2c_config_db);
	iowrite8(-1, &bootparam->h2c_shutdown_db);
	mic_notify_host(MIC_CRASHED);
	return NOTIFY_DONE;
}

static struct notifier_block mic_panic = {
	.notifier_call  = mic_panic_event,
};

static irqreturn_t mic_shutdown_isr(int irq, void *data)
{
	struct mic_driver *mdrv = g_drv;
	struct mic_bootparam __iomem *bootparam = mdrv->dp;

	mic_ack_interrupt(&g_drv->mdev);
	if (ioread8(&bootparam->shutdown_card))
		orderly_poweroff(true);
	return IRQ_HANDLED;
}

static int mic_shutdown_init(void)
{
	int rc = 0;
	struct mic_driver *mdrv = g_drv;
	struct mic_bootparam __iomem *bootparam = mdrv->dp;
	int shutdown_db;

	shutdown_db = mic_next_card_db();
	shutdown_cookie = mic_request_card_irq(mic_shutdown_isr,
			"Shutdown", mdrv, shutdown_db);
	if (IS_ERR(shutdown_cookie))
		rc = PTR_ERR(shutdown_cookie);
	else
		iowrite8(shutdown_db, &bootparam->h2c_shutdown_db);
	return rc;
}

static void mic_shutdown_uninit(void)
{
	struct mic_driver *mdrv = g_drv;
	struct mic_bootparam __iomem *bootparam = mdrv->dp;

	iowrite8(-1, &bootparam->h2c_shutdown_db);
	mic_free_card_irq(shutdown_cookie, mdrv);
}

static int __init mic_dp_init(void)
{
	struct mic_driver *mdrv = g_drv;
	struct mic_device *mdev = &mdrv->mdev;
	struct mic_bootparam __iomem *bootparam;
	u64 lo, hi, dp_dma_addr;
	u32 magic;

	lo = mic_read_spad(&mdrv->mdev, MIC_DPLO_SPAD);
	hi = mic_read_spad(&mdrv->mdev, MIC_DPHI_SPAD);

	dp_dma_addr = lo | (hi << 32);
	mdrv->dp = mic_card_map(mdev, dp_dma_addr, MIC_DP_SIZE);
	if (!mdrv->dp) {
		dev_err(mdrv->dev, "Cannot remap Aperture BAR\n");
		return -ENOMEM;
	}
	bootparam = mdrv->dp;
	magic = ioread32(&bootparam->magic);
	if (MIC_MAGIC != magic) {
		dev_err(mdrv->dev, "bootparam magic mismatch 0x%x\n", magic);
		return -EIO;
	}
	return 0;
}

/* Uninitialize the device page */
static void mic_dp_uninit(void)
{
	mic_card_unmap(&g_drv->mdev, g_drv->dp);
}

/**
 * mic_request_card_irq - request an irq.
 *
 * @func: The callback function that handles the interrupt.
 * @name: The ASCII name of the callee requesting the irq.
 * @data: private data that is returned back when calling the
 * function handler.
 * @index: The doorbell index of the requester.
 *
 * returns: The cookie that is transparent to the caller. Passed
 * back when calling mic_free_irq. An appropriate error code
 * is returned on failure. Caller needs to use IS_ERR(return_val)
 * to check for failure and PTR_ERR(return_val) to obtained the
 * error code.
 *
 */
struct mic_irq *mic_request_card_irq(irqreturn_t (*func)(int irq, void *data),
	const char *name, void *data, int index)
{
	int rc = 0;
	unsigned long cookie;
	struct mic_driver *mdrv = g_drv;

	rc  = request_irq(mic_db_to_irq(mdrv, index), func,
		0, name, data);
	if (rc) {
		dev_err(mdrv->dev, "request_irq failed rc = %d\n", rc);
		goto err;
	}
	mdrv->irq_info.irq_usage_count[index]++;
	cookie = index;
	return (struct mic_irq *)cookie;
err:
	return ERR_PTR(rc);

}

/**
 * mic_free_card_irq - free irq.
 *
 * @cookie: cookie obtained during a successful call to mic_request_irq
 * @data: private data specified by the calling function during the
 * mic_request_irq
 *
 * returns: none.
 */
void mic_free_card_irq(struct mic_irq *cookie, void *data)
{
	int index;
	struct mic_driver *mdrv = g_drv;

	index = (unsigned long)cookie & 0xFFFFU;
	free_irq(mic_db_to_irq(mdrv, index), data);
	mdrv->irq_info.irq_usage_count[index]--;
}

/**
 * mic_next_card_db - Get the doorbell with minimum usage count.
 *
 * Returns the irq index.
 */
int mic_next_card_db(void)
{
	int i;
	int index = 0;
	struct mic_driver *mdrv = g_drv;

	for (i = 0; i < mdrv->intr_info.num_intr; i++) {
		if (mdrv->irq_info.irq_usage_count[i] <
			mdrv->irq_info.irq_usage_count[index])
			index = i;
	}

	return index;
}

/**
 * mic_init_irq - Initialize irq information.
 *
 * Returns 0 in success. Appropriate error code on failure.
 */
static int mic_init_irq(void)
{
	struct mic_driver *mdrv = g_drv;

	mdrv->irq_info.irq_usage_count = kzalloc((sizeof(u32) *
			mdrv->intr_info.num_intr),
			GFP_KERNEL);
	if (!mdrv->irq_info.irq_usage_count)
		return -ENOMEM;
	return 0;
}

/**
 * mic_uninit_irq - Uninitialize irq information.
 *
 * None.
 */
static void mic_uninit_irq(void)
{
	struct mic_driver *mdrv = g_drv;

	kfree(mdrv->irq_info.irq_usage_count);
}

/*
 * mic_driver_init - MIC driver initialization tasks.
 *
 * Returns 0 in success. Appropriate error code on failure.
 */
int __init mic_driver_init(struct mic_driver *mdrv)
{
	int rc;

	g_drv = mdrv;
	/*
	 * Unloading the card module is not supported. The MIC card module
	 * handles fundamental operations like host/card initiated shutdowns
	 * and informing the host about card crashes and cannot be unloaded.
	 */
	if (!try_module_get(mdrv->dev->driver->owner)) {
		rc = -ENODEV;
		goto done;
	}
	rc = mic_dp_init();
	if (rc)
		goto put;
	rc = mic_init_irq();
	if (rc)
		goto dp_uninit;
	rc = mic_shutdown_init();
	if (rc)
		goto irq_uninit;
	rc = mic_devices_init(mdrv);
	if (rc)
		goto shutdown_uninit;
	mic_create_card_debug_dir(mdrv);
	atomic_notifier_chain_register(&panic_notifier_list, &mic_panic);
done:
	return rc;
shutdown_uninit:
	mic_shutdown_uninit();
irq_uninit:
	mic_uninit_irq();
dp_uninit:
	mic_dp_uninit();
put:
	module_put(mdrv->dev->driver->owner);
	return rc;
}

/*
 * mic_driver_uninit - MIC driver uninitialization tasks.
 *
 * Returns None
 */
void mic_driver_uninit(struct mic_driver *mdrv)
{
	mic_delete_card_debug_dir(mdrv);
	mic_devices_uninit(mdrv);
	/*
	 * Inform the host about the shutdown status i.e. poweroff/restart etc.
	 * The module cannot be unloaded so the only code path to call
	 * mic_devices_uninit(..) is the shutdown callback.
	 */
	mic_notify_host(system_state);
	mic_shutdown_uninit();
	mic_uninit_irq();
	mic_dp_uninit();
	module_put(mdrv->dev->driver->owner);
}