xref: /f-stack/dpdk/kernel/linux/igb_uio/igb_uio.c (revision 6b8a3e40)
1 // SPDX-License-Identifier: GPL-2.0
2 /*-
3  * Copyright(c) 2010-2017 Intel Corporation. All rights reserved.
4  */
5 
6 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
7 
8 #include <linux/device.h>
9 #include <linux/module.h>
10 #include <linux/pci.h>
11 #include <linux/uio_driver.h>
12 #include <linux/io.h>
13 #include <linux/irq.h>
14 #include <linux/msi.h>
15 #include <linux/version.h>
16 #include <linux/slab.h>
17 
18 /**
19  * These enum and macro definitions are copied from the
20  * file rte_pci_dev_features.h
21  */
22 enum rte_intr_mode {
23 	RTE_INTR_MODE_NONE = 0,
24 	RTE_INTR_MODE_LEGACY,
25 	RTE_INTR_MODE_MSI,
26 	RTE_INTR_MODE_MSIX
27 };
28 #define RTE_INTR_MODE_NONE_NAME "none"
29 #define RTE_INTR_MODE_LEGACY_NAME "legacy"
30 #define RTE_INTR_MODE_MSI_NAME "msi"
31 #define RTE_INTR_MODE_MSIX_NAME "msix"
32 
33 
34 #include "compat.h"
35 
36 /**
37  * A structure describing the private information for a uio device.
38  */
39 struct rte_uio_pci_dev {
40 	struct uio_info info;
41 	struct pci_dev *pdev;
42 	enum rte_intr_mode mode;
43 	atomic_t refcnt;
44 };
45 
46 static int wc_activate;
47 static char *intr_mode;
48 static enum rte_intr_mode igbuio_intr_mode_preferred = RTE_INTR_MODE_MSIX;
49 /* sriov sysfs */
50 static ssize_t
show_max_vfs(struct device * dev,struct device_attribute * attr,char * buf)51 show_max_vfs(struct device *dev, struct device_attribute *attr,
52 	     char *buf)
53 {
54 	return snprintf(buf, 10, "%u\n", dev_num_vf(dev));
55 }
56 
57 static ssize_t
store_max_vfs(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)58 store_max_vfs(struct device *dev, struct device_attribute *attr,
59 	      const char *buf, size_t count)
60 {
61 	int err = 0;
62 	unsigned long max_vfs;
63 	struct pci_dev *pdev = to_pci_dev(dev);
64 
65 	if (0 != kstrtoul(buf, 0, &max_vfs))
66 		return -EINVAL;
67 
68 	if (0 == max_vfs)
69 		pci_disable_sriov(pdev);
70 	else if (0 == pci_num_vf(pdev))
71 		err = pci_enable_sriov(pdev, max_vfs);
72 	else /* do nothing if change max_vfs number */
73 		err = -EINVAL;
74 
75 	return err ? err : count;
76 }
77 
78 static DEVICE_ATTR(max_vfs, S_IRUGO | S_IWUSR, show_max_vfs, store_max_vfs);
79 
80 static struct attribute *dev_attrs[] = {
81 	&dev_attr_max_vfs.attr,
82 	NULL,
83 };
84 
85 static const struct attribute_group dev_attr_grp = {
86 	.attrs = dev_attrs,
87 };
88 
89 #ifndef HAVE_PCI_MSI_MASK_IRQ
90 /*
91  * It masks the msix on/off of generating MSI-X messages.
92  */
93 static void
igbuio_msix_mask_irq(struct msi_desc * desc,s32 state)94 igbuio_msix_mask_irq(struct msi_desc *desc, s32 state)
95 {
96 	u32 mask_bits = desc->masked;
97 	unsigned int offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
98 						PCI_MSIX_ENTRY_VECTOR_CTRL;
99 
100 	if (state != 0)
101 		mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT;
102 	else
103 		mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
104 
105 	if (mask_bits != desc->masked) {
106 		writel(mask_bits, desc->mask_base + offset);
107 		readl(desc->mask_base);
108 		desc->masked = mask_bits;
109 	}
110 }
111 
112 /*
113  * It masks the msi on/off of generating MSI messages.
114  */
115 static void
igbuio_msi_mask_irq(struct pci_dev * pdev,struct msi_desc * desc,int32_t state)116 igbuio_msi_mask_irq(struct pci_dev *pdev, struct msi_desc *desc, int32_t state)
117 {
118 	u32 mask_bits = desc->masked;
119 	u32 offset = desc->irq - pdev->irq;
120 	u32 mask = 1 << offset;
121 
122 	if (!desc->msi_attrib.maskbit)
123 		return;
124 
125 	if (state != 0)
126 		mask_bits &= ~mask;
127 	else
128 		mask_bits |= mask;
129 
130 	if (mask_bits != desc->masked) {
131 		pci_write_config_dword(pdev, desc->mask_pos, mask_bits);
132 		desc->masked = mask_bits;
133 	}
134 }
135 
136 static void
igbuio_mask_irq(struct pci_dev * pdev,enum rte_intr_mode mode,s32 irq_state)137 igbuio_mask_irq(struct pci_dev *pdev, enum rte_intr_mode mode, s32 irq_state)
138 {
139 	struct msi_desc *desc;
140 	struct list_head *msi_list;
141 
142 #ifdef HAVE_MSI_LIST_IN_GENERIC_DEVICE
143 	msi_list = &pdev->dev.msi_list;
144 #else
145 	msi_list = &pdev->msi_list;
146 #endif
147 
148 	if (mode == RTE_INTR_MODE_MSIX) {
149 		list_for_each_entry(desc, msi_list, list)
150 			igbuio_msix_mask_irq(desc, irq_state);
151 	} else if (mode == RTE_INTR_MODE_MSI) {
152 		list_for_each_entry(desc, msi_list, list)
153 			igbuio_msi_mask_irq(pdev, desc, irq_state);
154 	}
155 }
156 #endif
157 
158 /**
159  * This is the irqcontrol callback to be registered to uio_info.
160  * It can be used to disable/enable interrupt from user space processes.
161  *
162  * @param info
163  *  pointer to uio_info.
164  * @param irq_state
165  *  state value. 1 to enable interrupt, 0 to disable interrupt.
166  *
167  * @return
168  *  - On success, 0.
169  *  - On failure, a negative value.
170  */
171 static int
igbuio_pci_irqcontrol(struct uio_info * info,s32 irq_state)172 igbuio_pci_irqcontrol(struct uio_info *info, s32 irq_state)
173 {
174 	struct rte_uio_pci_dev *udev = info->priv;
175 	struct pci_dev *pdev = udev->pdev;
176 
177 #ifdef HAVE_PCI_MSI_MASK_IRQ
178 	struct irq_data *irq = irq_get_irq_data(udev->info.irq);
179 #endif
180 
181 	pci_cfg_access_lock(pdev);
182 
183 	if (udev->mode == RTE_INTR_MODE_MSIX || udev->mode == RTE_INTR_MODE_MSI) {
184 #ifdef HAVE_PCI_MSI_MASK_IRQ
185 		if (irq_state == 1)
186 			pci_msi_unmask_irq(irq);
187 		else
188 			pci_msi_mask_irq(irq);
189 #else
190 		igbuio_mask_irq(pdev, udev->mode, irq_state);
191 #endif
192 	}
193 
194 	if (udev->mode == RTE_INTR_MODE_LEGACY)
195 		pci_intx(pdev, !!irq_state);
196 
197 	pci_cfg_access_unlock(pdev);
198 
199 	return 0;
200 }
201 
202 /**
203  * This is interrupt handler which will check if the interrupt is for the right device.
204  * If yes, disable it here and will be enable later.
205  */
206 static irqreturn_t
igbuio_pci_irqhandler(int irq,void * dev_id)207 igbuio_pci_irqhandler(int irq, void *dev_id)
208 {
209 	struct rte_uio_pci_dev *udev = (struct rte_uio_pci_dev *)dev_id;
210 	struct uio_info *info = &udev->info;
211 
212 	/* Legacy mode need to mask in hardware */
213 	if (udev->mode == RTE_INTR_MODE_LEGACY &&
214 	    !pci_check_and_mask_intx(udev->pdev))
215 		return IRQ_NONE;
216 
217 	uio_event_notify(info);
218 
219 	/* Message signal mode, no share IRQ and automasked */
220 	return IRQ_HANDLED;
221 }
222 
223 static int
igbuio_pci_enable_interrupts(struct rte_uio_pci_dev * udev)224 igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev)
225 {
226 	int err = 0;
227 #ifndef HAVE_ALLOC_IRQ_VECTORS
228 	struct msix_entry msix_entry;
229 #endif
230 
231 	switch (igbuio_intr_mode_preferred) {
232 	case RTE_INTR_MODE_MSIX:
233 		/* Only 1 msi-x vector needed */
234 #ifndef HAVE_ALLOC_IRQ_VECTORS
235 		msix_entry.entry = 0;
236 		if (pci_enable_msix(udev->pdev, &msix_entry, 1) == 0) {
237 			dev_dbg(&udev->pdev->dev, "using MSI-X");
238 			udev->info.irq_flags = IRQF_NO_THREAD;
239 			udev->info.irq = msix_entry.vector;
240 			udev->mode = RTE_INTR_MODE_MSIX;
241 			break;
242 		}
243 #else
244 		if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSIX) == 1) {
245 			dev_dbg(&udev->pdev->dev, "using MSI-X");
246 			udev->info.irq_flags = IRQF_NO_THREAD;
247 			udev->info.irq = pci_irq_vector(udev->pdev, 0);
248 			udev->mode = RTE_INTR_MODE_MSIX;
249 			break;
250 		}
251 #endif
252 
253 	/* falls through - to MSI */
254 	case RTE_INTR_MODE_MSI:
255 #ifndef HAVE_ALLOC_IRQ_VECTORS
256 		if (pci_enable_msi(udev->pdev) == 0) {
257 			dev_dbg(&udev->pdev->dev, "using MSI");
258 			udev->info.irq_flags = IRQF_NO_THREAD;
259 			udev->info.irq = udev->pdev->irq;
260 			udev->mode = RTE_INTR_MODE_MSI;
261 			break;
262 		}
263 #else
264 		if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSI) == 1) {
265 			dev_dbg(&udev->pdev->dev, "using MSI");
266 			udev->info.irq_flags = IRQF_NO_THREAD;
267 			udev->info.irq = pci_irq_vector(udev->pdev, 0);
268 			udev->mode = RTE_INTR_MODE_MSI;
269 			break;
270 		}
271 #endif
272 	/* falls through - to INTX */
273 	case RTE_INTR_MODE_LEGACY:
274 		if (pci_intx_mask_supported(udev->pdev)) {
275 			dev_dbg(&udev->pdev->dev, "using INTX");
276 			udev->info.irq_flags = IRQF_SHARED | IRQF_NO_THREAD;
277 			udev->info.irq = udev->pdev->irq;
278 			udev->mode = RTE_INTR_MODE_LEGACY;
279 			break;
280 		}
281 		dev_notice(&udev->pdev->dev, "PCI INTX mask not supported\n");
282 	/* falls through - to no IRQ */
283 	case RTE_INTR_MODE_NONE:
284 		udev->mode = RTE_INTR_MODE_NONE;
285 		udev->info.irq = UIO_IRQ_NONE;
286 		break;
287 
288 	default:
289 		dev_err(&udev->pdev->dev, "invalid IRQ mode %u",
290 			igbuio_intr_mode_preferred);
291 		udev->info.irq = UIO_IRQ_NONE;
292 		err = -EINVAL;
293 	}
294 
295 	if (udev->info.irq != UIO_IRQ_NONE)
296 		err = request_irq(udev->info.irq, igbuio_pci_irqhandler,
297 				  udev->info.irq_flags, udev->info.name,
298 				  udev);
299 	dev_info(&udev->pdev->dev, "uio device registered with irq %ld\n",
300 		 udev->info.irq);
301 
302 	return err;
303 }
304 
305 static void
igbuio_pci_disable_interrupts(struct rte_uio_pci_dev * udev)306 igbuio_pci_disable_interrupts(struct rte_uio_pci_dev *udev)
307 {
308 	if (udev->info.irq) {
309 		free_irq(udev->info.irq, udev);
310 		udev->info.irq = 0;
311 	}
312 
313 #ifndef HAVE_ALLOC_IRQ_VECTORS
314 	if (udev->mode == RTE_INTR_MODE_MSIX)
315 		pci_disable_msix(udev->pdev);
316 	if (udev->mode == RTE_INTR_MODE_MSI)
317 		pci_disable_msi(udev->pdev);
318 #else
319 	if (udev->mode == RTE_INTR_MODE_MSIX ||
320 	    udev->mode == RTE_INTR_MODE_MSI)
321 		pci_free_irq_vectors(udev->pdev);
322 #endif
323 }
324 
325 
326 /**
327  * This gets called while opening uio device file.
328  */
329 static int
igbuio_pci_open(struct uio_info * info,struct inode * inode)330 igbuio_pci_open(struct uio_info *info, struct inode *inode)
331 {
332 	struct rte_uio_pci_dev *udev = info->priv;
333 	struct pci_dev *dev = udev->pdev;
334 	int err;
335 
336 	if (atomic_inc_return(&udev->refcnt) != 1)
337 		return 0;
338 
339 	/* set bus master, which was cleared by the reset function */
340 	pci_set_master(dev);
341 
342 	/* enable interrupts */
343 	err = igbuio_pci_enable_interrupts(udev);
344 	if (err) {
345 		atomic_dec(&udev->refcnt);
346 		dev_err(&dev->dev, "Enable interrupt fails\n");
347 	}
348 	return err;
349 }
350 
351 static int
igbuio_pci_release(struct uio_info * info,struct inode * inode)352 igbuio_pci_release(struct uio_info *info, struct inode *inode)
353 {
354 	struct rte_uio_pci_dev *udev = info->priv;
355 	struct pci_dev *dev = udev->pdev;
356 
357 	if (atomic_dec_and_test(&udev->refcnt)) {
358 		/* disable interrupts */
359 		igbuio_pci_disable_interrupts(udev);
360 
361 		/* stop the device from further DMA */
362 		pci_clear_master(dev);
363 	}
364 
365 	return 0;
366 }
367 
368 /* Remap pci resources described by bar #pci_bar in uio resource n. */
369 static int
igbuio_pci_setup_iomem(struct pci_dev * dev,struct uio_info * info,int n,int pci_bar,const char * name)370 igbuio_pci_setup_iomem(struct pci_dev *dev, struct uio_info *info,
371 		       int n, int pci_bar, const char *name)
372 {
373 	unsigned long addr, len;
374 	void *internal_addr;
375 
376 	if (n >= ARRAY_SIZE(info->mem))
377 		return -EINVAL;
378 
379 	addr = pci_resource_start(dev, pci_bar);
380 	len = pci_resource_len(dev, pci_bar);
381 	if (addr == 0 || len == 0)
382 		return -1;
383 	if (wc_activate == 0) {
384 		internal_addr = ioremap(addr, len);
385 		if (internal_addr == NULL)
386 			return -1;
387 	} else {
388 		internal_addr = NULL;
389 	}
390 	info->mem[n].name = name;
391 	info->mem[n].addr = addr;
392 	info->mem[n].internal_addr = internal_addr;
393 	info->mem[n].size = len;
394 	info->mem[n].memtype = UIO_MEM_PHYS;
395 	return 0;
396 }
397 
398 /* Get pci port io resources described by bar #pci_bar in uio resource n. */
399 static int
igbuio_pci_setup_ioport(struct pci_dev * dev,struct uio_info * info,int n,int pci_bar,const char * name)400 igbuio_pci_setup_ioport(struct pci_dev *dev, struct uio_info *info,
401 		int n, int pci_bar, const char *name)
402 {
403 	unsigned long addr, len;
404 
405 	if (n >= ARRAY_SIZE(info->port))
406 		return -EINVAL;
407 
408 	addr = pci_resource_start(dev, pci_bar);
409 	len = pci_resource_len(dev, pci_bar);
410 	if (addr == 0 || len == 0)
411 		return -EINVAL;
412 
413 	info->port[n].name = name;
414 	info->port[n].start = addr;
415 	info->port[n].size = len;
416 	info->port[n].porttype = UIO_PORT_X86;
417 
418 	return 0;
419 }
420 
421 /* Unmap previously ioremap'd resources */
422 static void
igbuio_pci_release_iomem(struct uio_info * info)423 igbuio_pci_release_iomem(struct uio_info *info)
424 {
425 	int i;
426 
427 	for (i = 0; i < MAX_UIO_MAPS; i++) {
428 		if (info->mem[i].internal_addr)
429 			iounmap(info->mem[i].internal_addr);
430 	}
431 }
432 
433 static int
igbuio_setup_bars(struct pci_dev * dev,struct uio_info * info)434 igbuio_setup_bars(struct pci_dev *dev, struct uio_info *info)
435 {
436 	int i, iom, iop, ret;
437 	unsigned long flags;
438 	static const char *bar_names[PCI_STD_RESOURCE_END + 1]  = {
439 		"BAR0",
440 		"BAR1",
441 		"BAR2",
442 		"BAR3",
443 		"BAR4",
444 		"BAR5",
445 	};
446 
447 	iom = 0;
448 	iop = 0;
449 
450 	for (i = 0; i < ARRAY_SIZE(bar_names); i++) {
451 		if (pci_resource_len(dev, i) != 0 &&
452 				pci_resource_start(dev, i) != 0) {
453 			flags = pci_resource_flags(dev, i);
454 			if (flags & IORESOURCE_MEM) {
455 				ret = igbuio_pci_setup_iomem(dev, info, iom,
456 							     i, bar_names[i]);
457 				if (ret != 0)
458 					return ret;
459 				iom++;
460 			} else if (flags & IORESOURCE_IO) {
461 				ret = igbuio_pci_setup_ioport(dev, info, iop,
462 							      i, bar_names[i]);
463 				if (ret != 0)
464 					return ret;
465 				iop++;
466 			}
467 		}
468 	}
469 
470 	return (iom != 0 || iop != 0) ? ret : -ENOENT;
471 }
472 
473 #if LINUX_VERSION_CODE < KERNEL_VERSION(3, 8, 0)
474 static int __devinit
475 #else
476 static int
477 #endif
igbuio_pci_probe(struct pci_dev * dev,const struct pci_device_id * id)478 igbuio_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
479 {
480 	struct rte_uio_pci_dev *udev;
481 	dma_addr_t map_dma_addr;
482 	void *map_addr;
483 	int err;
484 
485 #ifdef HAVE_PCI_IS_BRIDGE_API
486 	if (pci_is_bridge(dev)) {
487 		dev_warn(&dev->dev, "Ignoring PCI bridge device\n");
488 		return -ENODEV;
489 	}
490 #endif
491 
492 	udev = kzalloc(sizeof(struct rte_uio_pci_dev), GFP_KERNEL);
493 	if (!udev)
494 		return -ENOMEM;
495 
496 	/*
497 	 * enable device: ask low-level code to enable I/O and
498 	 * memory
499 	 */
500 	err = pci_enable_device(dev);
501 	if (err != 0) {
502 		dev_err(&dev->dev, "Cannot enable PCI device\n");
503 		goto fail_free;
504 	}
505 
506 	/* enable bus mastering on the device */
507 	pci_set_master(dev);
508 
509 	/* remap IO memory */
510 	err = igbuio_setup_bars(dev, &udev->info);
511 	if (err != 0)
512 		goto fail_release_iomem;
513 
514 	/* set 64-bit DMA mask */
515 	err = pci_set_dma_mask(dev,  DMA_BIT_MASK(64));
516 	if (err != 0) {
517 		dev_err(&dev->dev, "Cannot set DMA mask\n");
518 		goto fail_release_iomem;
519 	}
520 
521 	err = pci_set_consistent_dma_mask(dev, DMA_BIT_MASK(64));
522 	if (err != 0) {
523 		dev_err(&dev->dev, "Cannot set consistent DMA mask\n");
524 		goto fail_release_iomem;
525 	}
526 
527 	/* fill uio infos */
528 	udev->info.name = "igb_uio";
529 	udev->info.version = "0.1";
530 	udev->info.irqcontrol = igbuio_pci_irqcontrol;
531 	udev->info.open = igbuio_pci_open;
532 	udev->info.release = igbuio_pci_release;
533 	udev->info.priv = udev;
534 	udev->pdev = dev;
535 	atomic_set(&udev->refcnt, 0);
536 
537 	err = sysfs_create_group(&dev->dev.kobj, &dev_attr_grp);
538 	if (err != 0)
539 		goto fail_release_iomem;
540 
541 	/* register uio driver */
542 	err = uio_register_device(&dev->dev, &udev->info);
543 	if (err != 0)
544 		goto fail_remove_group;
545 
546 	pci_set_drvdata(dev, udev);
547 
548 	/*
549 	 * Doing a harmless dma mapping for attaching the device to
550 	 * the iommu identity mapping if kernel boots with iommu=pt.
551 	 * Note this is not a problem if no IOMMU at all.
552 	 */
553 	map_addr = dma_alloc_coherent(&dev->dev, 1024, &map_dma_addr,
554 			GFP_KERNEL);
555 	if (map_addr)
556 		memset(map_addr, 0, 1024);
557 
558 	if (!map_addr)
559 		dev_info(&dev->dev, "dma mapping failed\n");
560 	else {
561 		dev_info(&dev->dev, "mapping 1K dma=%#llx host=%p\n",
562 			 (unsigned long long)map_dma_addr, map_addr);
563 
564 		dma_free_coherent(&dev->dev, 1024, map_addr, map_dma_addr);
565 		dev_info(&dev->dev, "unmapping 1K dma=%#llx host=%p\n",
566 			 (unsigned long long)map_dma_addr, map_addr);
567 	}
568 
569 	return 0;
570 
571 fail_remove_group:
572 	sysfs_remove_group(&dev->dev.kobj, &dev_attr_grp);
573 fail_release_iomem:
574 	igbuio_pci_release_iomem(&udev->info);
575 	pci_disable_device(dev);
576 fail_free:
577 	kfree(udev);
578 
579 	return err;
580 }
581 
582 static void
igbuio_pci_remove(struct pci_dev * dev)583 igbuio_pci_remove(struct pci_dev *dev)
584 {
585 	struct rte_uio_pci_dev *udev = pci_get_drvdata(dev);
586 
587 	igbuio_pci_release(&udev->info, NULL);
588 
589 	sysfs_remove_group(&dev->dev.kobj, &dev_attr_grp);
590 	uio_unregister_device(&udev->info);
591 	igbuio_pci_release_iomem(&udev->info);
592 	pci_disable_device(dev);
593 	pci_set_drvdata(dev, NULL);
594 	kfree(udev);
595 }
596 
597 static int
igbuio_config_intr_mode(char * intr_str)598 igbuio_config_intr_mode(char *intr_str)
599 {
600 	if (!intr_str) {
601 		pr_info("Use MSIX interrupt by default\n");
602 		return 0;
603 	}
604 
605 	if (!strcmp(intr_str, RTE_INTR_MODE_MSIX_NAME)) {
606 		igbuio_intr_mode_preferred = RTE_INTR_MODE_MSIX;
607 		pr_info("Use MSIX interrupt\n");
608 	} else if (!strcmp(intr_str, RTE_INTR_MODE_MSI_NAME)) {
609 		igbuio_intr_mode_preferred = RTE_INTR_MODE_MSI;
610 		pr_info("Use MSI interrupt\n");
611 	} else if (!strcmp(intr_str, RTE_INTR_MODE_LEGACY_NAME)) {
612 		igbuio_intr_mode_preferred = RTE_INTR_MODE_LEGACY;
613 		pr_info("Use legacy interrupt\n");
614 	} else {
615 		pr_info("Error: bad parameter - %s\n", intr_str);
616 		return -EINVAL;
617 	}
618 
619 	return 0;
620 }
621 
622 static struct pci_driver igbuio_pci_driver = {
623 	.name = "igb_uio",
624 	.id_table = NULL,
625 	.probe = igbuio_pci_probe,
626 	.remove = igbuio_pci_remove,
627 };
628 
629 static int __init
igbuio_pci_init_module(void)630 igbuio_pci_init_module(void)
631 {
632 	int ret;
633 
634 	if (igbuio_kernel_is_locked_down()) {
635 		pr_err("Not able to use module, kernel lock down is enabled\n");
636 		return -EINVAL;
637 	}
638 
639 	if (wc_activate != 0)
640 		pr_info("wc_activate is set\n");
641 
642 	ret = igbuio_config_intr_mode(intr_mode);
643 	if (ret < 0)
644 		return ret;
645 
646 	return pci_register_driver(&igbuio_pci_driver);
647 }
648 
649 static void __exit
igbuio_pci_exit_module(void)650 igbuio_pci_exit_module(void)
651 {
652 	pci_unregister_driver(&igbuio_pci_driver);
653 }
654 
655 module_init(igbuio_pci_init_module);
656 module_exit(igbuio_pci_exit_module);
657 
658 module_param(intr_mode, charp, S_IRUGO);
659 MODULE_PARM_DESC(intr_mode,
660 "igb_uio interrupt mode (default=msix):\n"
661 "    " RTE_INTR_MODE_MSIX_NAME "       Use MSIX interrupt\n"
662 "    " RTE_INTR_MODE_MSI_NAME "        Use MSI interrupt\n"
663 "    " RTE_INTR_MODE_LEGACY_NAME "     Use Legacy interrupt\n"
664 "\n");
665 
666 module_param(wc_activate, int, 0);
667 MODULE_PARM_DESC(wc_activate,
668 "Activate support for write combining (WC) (default=0)\n"
669 "    0 - disable\n"
670 "    other - enable\n");
671 
672 MODULE_DESCRIPTION("UIO driver for Intel IGB PCI cards");
673 MODULE_LICENSE("GPL");
674 MODULE_AUTHOR("Intel Corporation");
675