1 // SPDX-License-Identifier: GPL-2.0-or-later
2 
3 #include <linux/kernel.h>
4 #include <linux/ioport.h>
5 #include <linux/bitmap.h>
6 #include <linux/pci.h>
7 
8 #include <asm/opal.h>
9 
10 #include "pci.h"
11 
12 /* for pci_dev_is_added() */
13 #include "../../../../drivers/pci/pci.h"
14 
15 /*
16  * The majority of the complexity in supporting SR-IOV on PowerNV comes from
17  * the need to put the MMIO space for each VF into a separate PE. Internally
18  * the PHB maps MMIO addresses to a specific PE using the "Memory BAR Table".
19  * The MBT historically only applied to the 64bit MMIO window of the PHB
20  * so it's common to see it referred to as the "M64BT".
21  *
22  * An MBT entry stores the mapped range as an <base>,<mask> pair. This forces
23  * the address range that we want to map to be power-of-two sized and aligned.
24  * For conventional PCI devices this isn't really an issue since PCI device BARs
25  * have the same requirement.
26  *
27  * For a SR-IOV BAR things are a little more awkward since size and alignment
28  * are not coupled. The alignment is set based on the the per-VF BAR size, but
29  * the total BAR area is: number-of-vfs * per-vf-size. The number of VFs
30  * isn't necessarily a power of two, so neither is the total size. To fix that
31  * we need to finesse (read: hack) the Linux BAR allocator so that it will
32  * allocate the SR-IOV BARs in a way that lets us map them using the MBT.
33  *
34  * The changes to size and alignment that we need to do depend on the "mode"
35  * of MBT entry that we use. We only support SR-IOV on PHB3 (IODA2) and above,
36  * so as a baseline we can assume that we have the following BAR modes
37  * available:
38  *
39  *   NB: $PE_COUNT is the number of PEs that the PHB supports.
40  *
41  * a) A segmented BAR that splits the mapped range into $PE_COUNT equally sized
42  *    segments. The n'th segment is mapped to the n'th PE.
43  * b) An un-segmented BAR that maps the whole address range to a specific PE.
44  *
45  *
46  * We prefer to use mode a) since it only requires one MBT entry per SR-IOV BAR
47  * For comparison b) requires one entry per-VF per-BAR, or:
48  * (num-vfs * num-sriov-bars) in total. To use a) we need the size of each segment
49  * to equal the size of the per-VF BAR area. So:
50  *
51  *	new_size = per-vf-size * number-of-PEs
52  *
53  * The alignment for the SR-IOV BAR also needs to be changed from per-vf-size
54  * to "new_size", calculated above. Implementing this is a convoluted process
55  * which requires several hooks in the PCI core:
56  *
57  * 1. In pcibios_add_device() we call pnv_pci_ioda_fixup_iov().
58  *
59  *    At this point the device has been probed and the device's BARs are sized,
60  *    but no resource allocations have been done. The SR-IOV BARs are sized
61  *    based on the maximum number of VFs supported by the device and we need
62  *    to increase that to new_size.
63  *
64  * 2. Later, when Linux actually assigns resources it tries to make the resource
65  *    allocations for each PCI bus as compact as possible. As a part of that it
66  *    sorts the BARs on a bus by their required alignment, which is calculated
67  *    using pci_resource_alignment().
68  *
69  *    For IOV resources this goes:
70  *    pci_resource_alignment()
71  *        pci_sriov_resource_alignment()
72  *            pcibios_sriov_resource_alignment()
73  *                pnv_pci_iov_resource_alignment()
74  *
75  *    Our hook overrides the default alignment, equal to the per-vf-size, with
76  *    new_size computed above.
77  *
78  * 3. When userspace enables VFs for a device:
79  *
80  *    sriov_enable()
81  *       pcibios_sriov_enable()
82  *           pnv_pcibios_sriov_enable()
83  *
84  *    This is where we actually allocate PE numbers for each VF and setup the
85  *    MBT mapping for each SR-IOV BAR. In steps 1) and 2) we setup an "arena"
86  *    where each MBT segment is equal in size to the VF BAR so we can shift
87  *    around the actual SR-IOV BAR location within this arena. We need this
88  *    ability because the PE space is shared by all devices on the same PHB.
89  *    When using mode a) described above segment 0 in maps to PE#0 which might
90  *    be already being used by another device on the PHB.
91  *
92  *    As a result we need allocate a contigious range of PE numbers, then shift
93  *    the address programmed into the SR-IOV BAR of the PF so that the address
94  *    of VF0 matches up with the segment corresponding to the first allocated
95  *    PE number. This is handled in pnv_pci_vf_resource_shift().
96  *
97  *    Once all that is done we return to the PCI core which then enables VFs,
98  *    scans them and creates pci_devs for each. The init process for a VF is
99  *    largely the same as a normal device, but the VF is inserted into the IODA
100  *    PE that we allocated for it rather than the PE associated with the bus.
101  *
102  * 4. When userspace disables VFs we unwind the above in
103  *    pnv_pcibios_sriov_disable(). Fortunately this is relatively simple since
104  *    we don't need to validate anything, just tear down the mappings and
105  *    move SR-IOV resource back to its "proper" location.
106  *
107  * That's how mode a) works. In theory mode b) (single PE mapping) is less work
108  * since we can map each individual VF with a separate BAR. However, there's a
109  * few limitations:
110  *
111  * 1) For IODA2 mode b) has a minimum alignment requirement of 32MB. This makes
112  *    it only usable for devices with very large per-VF BARs. Such devices are
113  *    similar to Big Foot. They definitely exist, but I've never seen one.
114  *
115  * 2) The number of MBT entries that we have is limited. PHB3 and PHB4 only
116  *    16 total and some are needed for. Most SR-IOV capable network cards can support
117  *    more than 16 VFs on each port.
118  *
119  * We use b) when using a) would use more than 1/4 of the entire 64 bit MMIO
120  * window of the PHB.
121  *
122  *
123  *
124  * PHB4 (IODA3) added a few new features that would be useful for SR-IOV. It
125  * allowed the MBT to map 32bit MMIO space in addition to 64bit which allows
126  * us to support SR-IOV BARs in the 32bit MMIO window. This is useful since
127  * the Linux BAR allocation will place any BAR marked as non-prefetchable into
128  * the non-prefetchable bridge window, which is 32bit only. It also added two
129  * new modes:
130  *
131  * c) A segmented BAR similar to a), but each segment can be individually
132  *    mapped to any PE. This is matches how the 32bit MMIO window worked on
133  *    IODA1&2.
134  *
135  * d) A segmented BAR with 8, 64, or 128 segments. This works similarly to a),
136  *    but with fewer segments and configurable base PE.
137  *
138  *    i.e. The n'th segment maps to the (n + base)'th PE.
139  *
140  *    The base PE is also required to be a multiple of the window size.
141  *
142  * Unfortunately, the OPAL API doesn't currently (as of skiboot v6.6) allow us
143  * to exploit any of the IODA3 features.
144  */
145 
146 static void pnv_pci_ioda_fixup_iov_resources(struct pci_dev *pdev)
147 {
148 	struct pnv_phb *phb = pci_bus_to_pnvhb(pdev->bus);
149 	const resource_size_t gate = phb->ioda.m64_segsize >> 2;
150 	struct resource *res;
151 	int i;
152 	resource_size_t size, total_vf_bar_sz;
153 	struct pnv_iov_data *iov;
154 	int mul, total_vfs;
155 
156 	iov = kzalloc(sizeof(*iov), GFP_KERNEL);
157 	if (!iov)
158 		goto disable_iov;
159 	pdev->dev.archdata.iov_data = iov;
160 
161 	total_vfs = pci_sriov_get_totalvfs(pdev);
162 	mul = phb->ioda.total_pe_num;
163 	total_vf_bar_sz = 0;
164 
165 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
166 		res = &pdev->resource[i + PCI_IOV_RESOURCES];
167 		if (!res->flags || res->parent)
168 			continue;
169 		if (!pnv_pci_is_m64_flags(res->flags)) {
170 			dev_warn(&pdev->dev, "Don't support SR-IOV with non M64 VF BAR%d: %pR. \n",
171 				 i, res);
172 			goto disable_iov;
173 		}
174 
175 		total_vf_bar_sz += pci_iov_resource_size(pdev,
176 				i + PCI_IOV_RESOURCES);
177 
178 		/*
179 		 * If bigger than quarter of M64 segment size, just round up
180 		 * power of two.
181 		 *
182 		 * Generally, one M64 BAR maps one IOV BAR. To avoid conflict
183 		 * with other devices, IOV BAR size is expanded to be
184 		 * (total_pe * VF_BAR_size).  When VF_BAR_size is half of M64
185 		 * segment size , the expanded size would equal to half of the
186 		 * whole M64 space size, which will exhaust the M64 Space and
187 		 * limit the system flexibility.  This is a design decision to
188 		 * set the boundary to quarter of the M64 segment size.
189 		 */
190 		if (total_vf_bar_sz > gate) {
191 			mul = roundup_pow_of_two(total_vfs);
192 			dev_info(&pdev->dev,
193 				"VF BAR Total IOV size %llx > %llx, roundup to %d VFs\n",
194 				total_vf_bar_sz, gate, mul);
195 			iov->m64_single_mode = true;
196 			break;
197 		}
198 	}
199 
200 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
201 		res = &pdev->resource[i + PCI_IOV_RESOURCES];
202 		if (!res->flags || res->parent)
203 			continue;
204 
205 		size = pci_iov_resource_size(pdev, i + PCI_IOV_RESOURCES);
206 		/*
207 		 * On PHB3, the minimum size alignment of M64 BAR in single
208 		 * mode is 32MB.
209 		 */
210 		if (iov->m64_single_mode && (size < SZ_32M))
211 			goto disable_iov;
212 
213 		dev_dbg(&pdev->dev, " Fixing VF BAR%d: %pR to\n", i, res);
214 		res->end = res->start + size * mul - 1;
215 		dev_dbg(&pdev->dev, "                       %pR\n", res);
216 		dev_info(&pdev->dev, "VF BAR%d: %pR (expanded to %d VFs for PE alignment)",
217 			 i, res, mul);
218 	}
219 	iov->vfs_expanded = mul;
220 
221 	return;
222 
223 disable_iov:
224 	/* Save ourselves some MMIO space by disabling the unusable BARs */
225 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
226 		res = &pdev->resource[i + PCI_IOV_RESOURCES];
227 		res->flags = 0;
228 		res->end = res->start - 1;
229 	}
230 
231 	pdev->dev.archdata.iov_data = NULL;
232 	kfree(iov);
233 }
234 
235 void pnv_pci_ioda_fixup_iov(struct pci_dev *pdev)
236 {
237 	if (WARN_ON(pci_dev_is_added(pdev)))
238 		return;
239 
240 	if (pdev->is_virtfn) {
241 		struct pnv_ioda_pe *pe = pnv_ioda_get_pe(pdev);
242 
243 		/*
244 		 * VF PEs are single-device PEs so their pdev pointer needs to
245 		 * be set. The pdev doesn't exist when the PE is allocated (in
246 		 * (pcibios_sriov_enable()) so we fix it up here.
247 		 */
248 		pe->pdev = pdev;
249 		WARN_ON(!(pe->flags & PNV_IODA_PE_VF));
250 	} else if (pdev->is_physfn) {
251 		/*
252 		 * For PFs adjust their allocated IOV resources to match what
253 		 * the PHB can support using it's M64 BAR table.
254 		 */
255 		pnv_pci_ioda_fixup_iov_resources(pdev);
256 	}
257 }
258 
259 resource_size_t pnv_pci_iov_resource_alignment(struct pci_dev *pdev,
260 						      int resno)
261 {
262 	struct pnv_phb *phb = pci_bus_to_pnvhb(pdev->bus);
263 	struct pnv_iov_data *iov = pnv_iov_get(pdev);
264 	resource_size_t align;
265 
266 	/*
267 	 * On PowerNV platform, IOV BAR is mapped by M64 BAR to enable the
268 	 * SR-IOV. While from hardware perspective, the range mapped by M64
269 	 * BAR should be size aligned.
270 	 *
271 	 * When IOV BAR is mapped with M64 BAR in Single PE mode, the extra
272 	 * powernv-specific hardware restriction is gone. But if just use the
273 	 * VF BAR size as the alignment, PF BAR / VF BAR may be allocated with
274 	 * in one segment of M64 #15, which introduces the PE conflict between
275 	 * PF and VF. Based on this, the minimum alignment of an IOV BAR is
276 	 * m64_segsize.
277 	 *
278 	 * This function returns the total IOV BAR size if M64 BAR is in
279 	 * Shared PE mode or just VF BAR size if not.
280 	 * If the M64 BAR is in Single PE mode, return the VF BAR size or
281 	 * M64 segment size if IOV BAR size is less.
282 	 */
283 	align = pci_iov_resource_size(pdev, resno);
284 
285 	/*
286 	 * iov can be null if we have an SR-IOV device with IOV BAR that can't
287 	 * be placed in the m64 space (i.e. The BAR is 32bit or non-prefetch).
288 	 * In that case we don't allow VFs to be enabled so just return the
289 	 * default alignment.
290 	 */
291 	if (!iov)
292 		return align;
293 	if (!iov->vfs_expanded)
294 		return align;
295 	if (iov->m64_single_mode)
296 		return max(align, (resource_size_t)phb->ioda.m64_segsize);
297 
298 	return iov->vfs_expanded * align;
299 }
300 
301 static int pnv_pci_vf_release_m64(struct pci_dev *pdev, u16 num_vfs)
302 {
303 	struct pnv_iov_data   *iov;
304 	struct pnv_phb        *phb;
305 	int window_id;
306 
307 	phb = pci_bus_to_pnvhb(pdev->bus);
308 	iov = pnv_iov_get(pdev);
309 
310 	for_each_set_bit(window_id, iov->used_m64_bar_mask, MAX_M64_BARS) {
311 		opal_pci_phb_mmio_enable(phb->opal_id,
312 					 OPAL_M64_WINDOW_TYPE,
313 					 window_id,
314 					 0);
315 
316 		clear_bit(window_id, &phb->ioda.m64_bar_alloc);
317 	}
318 
319 	return 0;
320 }
321 
322 static int pnv_pci_vf_assign_m64(struct pci_dev *pdev, u16 num_vfs)
323 {
324 	struct pnv_iov_data   *iov;
325 	struct pnv_phb        *phb;
326 	unsigned int           win;
327 	struct resource       *res;
328 	int                    i, j;
329 	int64_t                rc;
330 	int                    total_vfs;
331 	resource_size_t        size, start;
332 	int                    pe_num;
333 	int                    m64_bars;
334 
335 	phb = pci_bus_to_pnvhb(pdev->bus);
336 	iov = pnv_iov_get(pdev);
337 	total_vfs = pci_sriov_get_totalvfs(pdev);
338 
339 	if (iov->m64_single_mode)
340 		m64_bars = num_vfs;
341 	else
342 		m64_bars = 1;
343 
344 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
345 		res = &pdev->resource[i + PCI_IOV_RESOURCES];
346 		if (!res->flags || !res->parent)
347 			continue;
348 
349 		for (j = 0; j < m64_bars; j++) {
350 
351 			/* allocate a window ID for this BAR */
352 			do {
353 				win = find_next_zero_bit(&phb->ioda.m64_bar_alloc,
354 						phb->ioda.m64_bar_idx + 1, 0);
355 
356 				if (win >= phb->ioda.m64_bar_idx + 1)
357 					goto m64_failed;
358 			} while (test_and_set_bit(win, &phb->ioda.m64_bar_alloc));
359 			set_bit(win, iov->used_m64_bar_mask);
360 
361 			if (iov->m64_single_mode) {
362 				size = pci_iov_resource_size(pdev,
363 							PCI_IOV_RESOURCES + i);
364 				start = res->start + size * j;
365 			} else {
366 				size = resource_size(res);
367 				start = res->start;
368 			}
369 
370 			/* Map the M64 here */
371 			if (iov->m64_single_mode) {
372 				pe_num = iov->pe_num_map[j];
373 				rc = opal_pci_map_pe_mmio_window(phb->opal_id,
374 						pe_num, OPAL_M64_WINDOW_TYPE,
375 						win, 0);
376 			}
377 
378 			rc = opal_pci_set_phb_mem_window(phb->opal_id,
379 						 OPAL_M64_WINDOW_TYPE,
380 						 win,
381 						 start,
382 						 0, /* unused */
383 						 size);
384 
385 
386 			if (rc != OPAL_SUCCESS) {
387 				dev_err(&pdev->dev, "Failed to map M64 window #%d: %lld\n",
388 					win, rc);
389 				goto m64_failed;
390 			}
391 
392 			if (iov->m64_single_mode)
393 				rc = opal_pci_phb_mmio_enable(phb->opal_id,
394 				     OPAL_M64_WINDOW_TYPE, win, 2);
395 			else
396 				rc = opal_pci_phb_mmio_enable(phb->opal_id,
397 				     OPAL_M64_WINDOW_TYPE, win, 1);
398 
399 			if (rc != OPAL_SUCCESS) {
400 				dev_err(&pdev->dev, "Failed to enable M64 window #%d: %llx\n",
401 					win, rc);
402 				goto m64_failed;
403 			}
404 		}
405 	}
406 	return 0;
407 
408 m64_failed:
409 	pnv_pci_vf_release_m64(pdev, num_vfs);
410 	return -EBUSY;
411 }
412 
413 static void pnv_ioda_release_vf_PE(struct pci_dev *pdev)
414 {
415 	struct pnv_phb        *phb;
416 	struct pnv_ioda_pe    *pe, *pe_n;
417 
418 	phb = pci_bus_to_pnvhb(pdev->bus);
419 
420 	if (!pdev->is_physfn)
421 		return;
422 
423 	/* FIXME: Use pnv_ioda_release_pe()? */
424 	list_for_each_entry_safe(pe, pe_n, &phb->ioda.pe_list, list) {
425 		if (pe->parent_dev != pdev)
426 			continue;
427 
428 		pnv_pci_ioda2_release_pe_dma(pe);
429 
430 		/* Remove from list */
431 		mutex_lock(&phb->ioda.pe_list_mutex);
432 		list_del(&pe->list);
433 		mutex_unlock(&phb->ioda.pe_list_mutex);
434 
435 		pnv_ioda_deconfigure_pe(phb, pe);
436 
437 		pnv_ioda_free_pe(pe);
438 	}
439 }
440 
441 static int pnv_pci_vf_resource_shift(struct pci_dev *dev, int offset)
442 {
443 	struct resource *res, res2;
444 	struct pnv_iov_data *iov;
445 	resource_size_t size;
446 	u16 num_vfs;
447 	int i;
448 
449 	if (!dev->is_physfn)
450 		return -EINVAL;
451 	iov = pnv_iov_get(dev);
452 
453 	/*
454 	 * "offset" is in VFs.  The M64 windows are sized so that when they
455 	 * are segmented, each segment is the same size as the IOV BAR.
456 	 * Each segment is in a separate PE, and the high order bits of the
457 	 * address are the PE number.  Therefore, each VF's BAR is in a
458 	 * separate PE, and changing the IOV BAR start address changes the
459 	 * range of PEs the VFs are in.
460 	 */
461 	num_vfs = iov->num_vfs;
462 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
463 		res = &dev->resource[i + PCI_IOV_RESOURCES];
464 		if (!res->flags || !res->parent)
465 			continue;
466 
467 		/*
468 		 * The actual IOV BAR range is determined by the start address
469 		 * and the actual size for num_vfs VFs BAR.  This check is to
470 		 * make sure that after shifting, the range will not overlap
471 		 * with another device.
472 		 */
473 		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
474 		res2.flags = res->flags;
475 		res2.start = res->start + (size * offset);
476 		res2.end = res2.start + (size * num_vfs) - 1;
477 
478 		if (res2.end > res->end) {
479 			dev_err(&dev->dev, "VF BAR%d: %pR would extend past %pR (trying to enable %d VFs shifted by %d)\n",
480 				i, &res2, res, num_vfs, offset);
481 			return -EBUSY;
482 		}
483 	}
484 
485 	/*
486 	 * Since M64 BAR shares segments among all possible 256 PEs,
487 	 * we have to shift the beginning of PF IOV BAR to make it start from
488 	 * the segment which belongs to the PE number assigned to the first VF.
489 	 * This creates a "hole" in the /proc/iomem which could be used for
490 	 * allocating other resources so we reserve this area below and
491 	 * release when IOV is released.
492 	 */
493 	for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
494 		res = &dev->resource[i + PCI_IOV_RESOURCES];
495 		if (!res->flags || !res->parent)
496 			continue;
497 
498 		size = pci_iov_resource_size(dev, i + PCI_IOV_RESOURCES);
499 		res2 = *res;
500 		res->start += size * offset;
501 
502 		dev_info(&dev->dev, "VF BAR%d: %pR shifted to %pR (%sabling %d VFs shifted by %d)\n",
503 			 i, &res2, res, (offset > 0) ? "En" : "Dis",
504 			 num_vfs, offset);
505 
506 		if (offset < 0) {
507 			devm_release_resource(&dev->dev, &iov->holes[i]);
508 			memset(&iov->holes[i], 0, sizeof(iov->holes[i]));
509 		}
510 
511 		pci_update_resource(dev, i + PCI_IOV_RESOURCES);
512 
513 		if (offset > 0) {
514 			iov->holes[i].start = res2.start;
515 			iov->holes[i].end = res2.start + size * offset - 1;
516 			iov->holes[i].flags = IORESOURCE_BUS;
517 			iov->holes[i].name = "pnv_iov_reserved";
518 			devm_request_resource(&dev->dev, res->parent,
519 					&iov->holes[i]);
520 		}
521 	}
522 	return 0;
523 }
524 
525 static void pnv_pci_sriov_disable(struct pci_dev *pdev)
526 {
527 	struct pnv_phb        *phb;
528 	struct pnv_ioda_pe    *pe;
529 	struct pnv_iov_data   *iov;
530 	u16                    num_vfs, i;
531 
532 	phb = pci_bus_to_pnvhb(pdev->bus);
533 	iov = pnv_iov_get(pdev);
534 	num_vfs = iov->num_vfs;
535 
536 	/* Release VF PEs */
537 	pnv_ioda_release_vf_PE(pdev);
538 
539 	if (phb->type == PNV_PHB_IODA2) {
540 		if (!iov->m64_single_mode)
541 			pnv_pci_vf_resource_shift(pdev, -*iov->pe_num_map);
542 
543 		/* Release M64 windows */
544 		pnv_pci_vf_release_m64(pdev, num_vfs);
545 
546 		/* Release PE numbers */
547 		if (iov->m64_single_mode) {
548 			for (i = 0; i < num_vfs; i++) {
549 				if (iov->pe_num_map[i] == IODA_INVALID_PE)
550 					continue;
551 
552 				pe = &phb->ioda.pe_array[iov->pe_num_map[i]];
553 				pnv_ioda_free_pe(pe);
554 			}
555 		} else
556 			bitmap_clear(phb->ioda.pe_alloc, *iov->pe_num_map, num_vfs);
557 		/* Releasing pe_num_map */
558 		kfree(iov->pe_num_map);
559 	}
560 }
561 
562 static void pnv_ioda_setup_vf_PE(struct pci_dev *pdev, u16 num_vfs)
563 {
564 	struct pnv_phb        *phb;
565 	struct pnv_ioda_pe    *pe;
566 	int                    pe_num;
567 	u16                    vf_index;
568 	struct pnv_iov_data   *iov;
569 	struct pci_dn         *pdn;
570 
571 	if (!pdev->is_physfn)
572 		return;
573 
574 	phb = pci_bus_to_pnvhb(pdev->bus);
575 	pdn = pci_get_pdn(pdev);
576 	iov = pnv_iov_get(pdev);
577 
578 	/* Reserve PE for each VF */
579 	for (vf_index = 0; vf_index < num_vfs; vf_index++) {
580 		int vf_devfn = pci_iov_virtfn_devfn(pdev, vf_index);
581 		int vf_bus = pci_iov_virtfn_bus(pdev, vf_index);
582 		struct pci_dn *vf_pdn;
583 
584 		if (iov->m64_single_mode)
585 			pe_num = iov->pe_num_map[vf_index];
586 		else
587 			pe_num = *iov->pe_num_map + vf_index;
588 
589 		pe = &phb->ioda.pe_array[pe_num];
590 		pe->pe_number = pe_num;
591 		pe->phb = phb;
592 		pe->flags = PNV_IODA_PE_VF;
593 		pe->pbus = NULL;
594 		pe->parent_dev = pdev;
595 		pe->mve_number = -1;
596 		pe->rid = (vf_bus << 8) | vf_devfn;
597 
598 		pe_info(pe, "VF %04d:%02d:%02d.%d associated with PE#%x\n",
599 			pci_domain_nr(pdev->bus), pdev->bus->number,
600 			PCI_SLOT(vf_devfn), PCI_FUNC(vf_devfn), pe_num);
601 
602 		if (pnv_ioda_configure_pe(phb, pe)) {
603 			/* XXX What do we do here ? */
604 			pnv_ioda_free_pe(pe);
605 			pe->pdev = NULL;
606 			continue;
607 		}
608 
609 		/* Put PE to the list */
610 		mutex_lock(&phb->ioda.pe_list_mutex);
611 		list_add_tail(&pe->list, &phb->ioda.pe_list);
612 		mutex_unlock(&phb->ioda.pe_list_mutex);
613 
614 		/* associate this pe to it's pdn */
615 		list_for_each_entry(vf_pdn, &pdn->parent->child_list, list) {
616 			if (vf_pdn->busno == vf_bus &&
617 			    vf_pdn->devfn == vf_devfn) {
618 				vf_pdn->pe_number = pe_num;
619 				break;
620 			}
621 		}
622 
623 		pnv_pci_ioda2_setup_dma_pe(phb, pe);
624 	}
625 }
626 
627 static int pnv_pci_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
628 {
629 	struct pnv_iov_data   *iov;
630 	struct pnv_phb        *phb;
631 	struct pnv_ioda_pe    *pe;
632 	int                    ret;
633 	u16                    i;
634 
635 	phb = pci_bus_to_pnvhb(pdev->bus);
636 	iov = pnv_iov_get(pdev);
637 
638 	if (phb->type == PNV_PHB_IODA2) {
639 		if (!iov->vfs_expanded) {
640 			dev_info(&pdev->dev,
641 				 "don't support this SRIOV device with non 64bit-prefetchable IOV BAR\n");
642 			return -ENOSPC;
643 		}
644 
645 		/*
646 		 * When M64 BARs functions in Single PE mode, the number of VFs
647 		 * could be enabled must be less than the number of M64 BARs.
648 		 */
649 		if (iov->m64_single_mode && num_vfs > phb->ioda.m64_bar_idx) {
650 			dev_info(&pdev->dev, "Not enough M64 BAR for VFs\n");
651 			return -EBUSY;
652 		}
653 
654 		/* Allocating pe_num_map */
655 		if (iov->m64_single_mode)
656 			iov->pe_num_map = kmalloc_array(num_vfs,
657 							sizeof(*iov->pe_num_map),
658 							GFP_KERNEL);
659 		else
660 			iov->pe_num_map = kmalloc(sizeof(*iov->pe_num_map), GFP_KERNEL);
661 
662 		if (!iov->pe_num_map)
663 			return -ENOMEM;
664 
665 		if (iov->m64_single_mode)
666 			for (i = 0; i < num_vfs; i++)
667 				iov->pe_num_map[i] = IODA_INVALID_PE;
668 
669 		/* Calculate available PE for required VFs */
670 		if (iov->m64_single_mode) {
671 			for (i = 0; i < num_vfs; i++) {
672 				pe = pnv_ioda_alloc_pe(phb);
673 				if (!pe) {
674 					ret = -EBUSY;
675 					goto m64_failed;
676 				}
677 
678 				iov->pe_num_map[i] = pe->pe_number;
679 			}
680 		} else {
681 			mutex_lock(&phb->ioda.pe_alloc_mutex);
682 			*iov->pe_num_map = bitmap_find_next_zero_area(
683 				phb->ioda.pe_alloc, phb->ioda.total_pe_num,
684 				0, num_vfs, 0);
685 			if (*iov->pe_num_map >= phb->ioda.total_pe_num) {
686 				mutex_unlock(&phb->ioda.pe_alloc_mutex);
687 				dev_info(&pdev->dev, "Failed to enable VF%d\n", num_vfs);
688 				kfree(iov->pe_num_map);
689 				return -EBUSY;
690 			}
691 			bitmap_set(phb->ioda.pe_alloc, *iov->pe_num_map, num_vfs);
692 			mutex_unlock(&phb->ioda.pe_alloc_mutex);
693 		}
694 		iov->num_vfs = num_vfs;
695 
696 		/* Assign M64 window accordingly */
697 		ret = pnv_pci_vf_assign_m64(pdev, num_vfs);
698 		if (ret) {
699 			dev_info(&pdev->dev, "Not enough M64 window resources\n");
700 			goto m64_failed;
701 		}
702 
703 		/*
704 		 * When using one M64 BAR to map one IOV BAR, we need to shift
705 		 * the IOV BAR according to the PE# allocated to the VFs.
706 		 * Otherwise, the PE# for the VF will conflict with others.
707 		 */
708 		if (!iov->m64_single_mode) {
709 			ret = pnv_pci_vf_resource_shift(pdev, *iov->pe_num_map);
710 			if (ret)
711 				goto m64_failed;
712 		}
713 	}
714 
715 	/* Setup VF PEs */
716 	pnv_ioda_setup_vf_PE(pdev, num_vfs);
717 
718 	return 0;
719 
720 m64_failed:
721 	if (iov->m64_single_mode) {
722 		for (i = 0; i < num_vfs; i++) {
723 			if (iov->pe_num_map[i] == IODA_INVALID_PE)
724 				continue;
725 
726 			pe = &phb->ioda.pe_array[iov->pe_num_map[i]];
727 			pnv_ioda_free_pe(pe);
728 		}
729 	} else
730 		bitmap_clear(phb->ioda.pe_alloc, *iov->pe_num_map, num_vfs);
731 
732 	/* Releasing pe_num_map */
733 	kfree(iov->pe_num_map);
734 
735 	return ret;
736 }
737 
738 int pnv_pcibios_sriov_disable(struct pci_dev *pdev)
739 {
740 	pnv_pci_sriov_disable(pdev);
741 
742 	/* Release PCI data */
743 	remove_sriov_vf_pdns(pdev);
744 	return 0;
745 }
746 
747 int pnv_pcibios_sriov_enable(struct pci_dev *pdev, u16 num_vfs)
748 {
749 	/* Allocate PCI data */
750 	add_sriov_vf_pdns(pdev);
751 
752 	return pnv_pci_sriov_enable(pdev, num_vfs);
753 }
754