1 /*
2 * Copyright (C) 2007-2011 Freescale Semiconductor, Inc.
3 *
4 * Author: Tony Li <tony.li@freescale.com>
5 * Jason Jin <Jason.jin@freescale.com>
6 *
7 * The hwirq alloc and free code reuse from sysdev/mpic_msi.c
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; version 2 of the
12 * License.
13 *
14 */
15 #include <linux/irq.h>
16 #include <linux/msi.h>
17 #include <linux/pci.h>
18 #include <linux/slab.h>
19 #include <linux/of_platform.h>
20 #include <linux/interrupt.h>
21 #include <linux/seq_file.h>
22 #include <sysdev/fsl_soc.h>
23 #include <asm/prom.h>
24 #include <asm/hw_irq.h>
25 #include <asm/ppc-pci.h>
26 #include <asm/mpic.h>
27 #include <asm/fsl_hcalls.h>
28
29 #include "fsl_msi.h"
30 #include "fsl_pci.h"
31
32 #define MSIIR_OFFSET_MASK 0xfffff
33 #define MSIIR_IBS_SHIFT 0
34 #define MSIIR_SRS_SHIFT 5
35 #define MSIIR1_IBS_SHIFT 4
36 #define MSIIR1_SRS_SHIFT 0
37 #define MSI_SRS_MASK 0xf
38 #define MSI_IBS_MASK 0x1f
39
40 #define msi_hwirq(msi, msir_index, intr_index) \
41 ((msir_index) << (msi)->srs_shift | \
42 ((intr_index) << (msi)->ibs_shift))
43
44 static LIST_HEAD(msi_head);
45
46 struct fsl_msi_feature {
47 u32 fsl_pic_ip;
48 u32 msiir_offset; /* Offset of MSIIR, relative to start of MSIR bank */
49 };
50
51 struct fsl_msi_cascade_data {
52 struct fsl_msi *msi_data;
53 int index;
54 int virq;
55 };
56
57 static inline u32 fsl_msi_read(u32 __iomem *base, unsigned int reg)
58 {
59 return in_be32(base + (reg >> 2));
60 }
61
62 /*
63 * We do not need this actually. The MSIR register has been read once
64 * in the cascade interrupt. So, this MSI interrupt has been acked
65 */
66 static void fsl_msi_end_irq(struct irq_data *d)
67 {
68 }
69
70 static void fsl_msi_print_chip(struct irq_data *irqd, struct seq_file *p)
71 {
72 struct fsl_msi *msi_data = irqd->domain->host_data;
73 irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
74 int cascade_virq, srs;
75
76 srs = (hwirq >> msi_data->srs_shift) & MSI_SRS_MASK;
77 cascade_virq = msi_data->cascade_array[srs]->virq;
78
79 seq_printf(p, " fsl-msi-%d", cascade_virq);
80 }
81
82
83 static struct irq_chip fsl_msi_chip = {
84 .irq_mask = pci_msi_mask_irq,
85 .irq_unmask = pci_msi_unmask_irq,
86 .irq_ack = fsl_msi_end_irq,
87 .irq_print_chip = fsl_msi_print_chip,
88 };
89
90 static int fsl_msi_host_map(struct irq_domain *h, unsigned int virq,
91 irq_hw_number_t hw)
92 {
93 struct fsl_msi *msi_data = h->host_data;
94 struct irq_chip *chip = &fsl_msi_chip;
95
96 irq_set_status_flags(virq, IRQ_TYPE_EDGE_FALLING);
97
98 irq_set_chip_data(virq, msi_data);
99 irq_set_chip_and_handler(virq, chip, handle_edge_irq);
100
101 return 0;
102 }
103
104 static const struct irq_domain_ops fsl_msi_host_ops = {
105 .map = fsl_msi_host_map,
106 };
107
108 static int fsl_msi_init_allocator(struct fsl_msi *msi_data)
109 {
110 int rc, hwirq;
111
112 rc = msi_bitmap_alloc(&msi_data->bitmap, NR_MSI_IRQS_MAX,
113 irq_domain_get_of_node(msi_data->irqhost));
114 if (rc)
115 return rc;
116
117 /*
118 * Reserve all the hwirqs
119 * The available hwirqs will be released in fsl_msi_setup_hwirq()
120 */
121 for (hwirq = 0; hwirq < NR_MSI_IRQS_MAX; hwirq++)
122 msi_bitmap_reserve_hwirq(&msi_data->bitmap, hwirq);
123
124 return 0;
125 }
126
127 static void fsl_teardown_msi_irqs(struct pci_dev *pdev)
128 {
129 struct msi_desc *entry;
130 struct fsl_msi *msi_data;
131 irq_hw_number_t hwirq;
132
133 for_each_pci_msi_entry(entry, pdev) {
134 if (entry->irq == NO_IRQ)
135 continue;
136 hwirq = virq_to_hw(entry->irq);
137 msi_data = irq_get_chip_data(entry->irq);
138 irq_set_msi_desc(entry->irq, NULL);
139 irq_dispose_mapping(entry->irq);
140 msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
141 }
142
143 return;
144 }
145
146 static void fsl_compose_msi_msg(struct pci_dev *pdev, int hwirq,
147 struct msi_msg *msg,
148 struct fsl_msi *fsl_msi_data)
149 {
150 struct fsl_msi *msi_data = fsl_msi_data;
151 struct pci_controller *hose = pci_bus_to_host(pdev->bus);
152 u64 address; /* Physical address of the MSIIR */
153 int len;
154 const __be64 *reg;
155
156 /* If the msi-address-64 property exists, then use it */
157 reg = of_get_property(hose->dn, "msi-address-64", &len);
158 if (reg && (len == sizeof(u64)))
159 address = be64_to_cpup(reg);
160 else
161 address = fsl_pci_immrbar_base(hose) + msi_data->msiir_offset;
162
163 msg->address_lo = lower_32_bits(address);
164 msg->address_hi = upper_32_bits(address);
165
166 /*
167 * MPIC version 2.0 has erratum PIC1. It causes
168 * that neither MSI nor MSI-X can work fine.
169 * This is a workaround to allow MSI-X to function
170 * properly. It only works for MSI-X, we prevent
171 * MSI on buggy chips in fsl_setup_msi_irqs().
172 */
173 if (msi_data->feature & MSI_HW_ERRATA_ENDIAN)
174 msg->data = __swab32(hwirq);
175 else
176 msg->data = hwirq;
177
178 pr_debug("%s: allocated srs: %d, ibs: %d\n", __func__,
179 (hwirq >> msi_data->srs_shift) & MSI_SRS_MASK,
180 (hwirq >> msi_data->ibs_shift) & MSI_IBS_MASK);
181 }
182
183 static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
184 {
185 struct pci_controller *hose = pci_bus_to_host(pdev->bus);
186 struct device_node *np;
187 phandle phandle = 0;
188 int rc, hwirq = -ENOMEM;
189 unsigned int virq;
190 struct msi_desc *entry;
191 struct msi_msg msg;
192 struct fsl_msi *msi_data;
193
194 if (type == PCI_CAP_ID_MSI) {
195 /*
196 * MPIC version 2.0 has erratum PIC1. For now MSI
197 * could not work. So check to prevent MSI from
198 * being used on the board with this erratum.
199 */
200 list_for_each_entry(msi_data, &msi_head, list)
201 if (msi_data->feature & MSI_HW_ERRATA_ENDIAN)
202 return -EINVAL;
203 }
204
205 /*
206 * If the PCI node has an fsl,msi property, then we need to use it
207 * to find the specific MSI.
208 */
209 np = of_parse_phandle(hose->dn, "fsl,msi", 0);
210 if (np) {
211 if (of_device_is_compatible(np, "fsl,mpic-msi") ||
212 of_device_is_compatible(np, "fsl,vmpic-msi") ||
213 of_device_is_compatible(np, "fsl,vmpic-msi-v4.3"))
214 phandle = np->phandle;
215 else {
216 dev_err(&pdev->dev,
217 "node %s has an invalid fsl,msi phandle %u\n",
218 hose->dn->full_name, np->phandle);
219 return -EINVAL;
220 }
221 }
222
223 for_each_pci_msi_entry(entry, pdev) {
224 /*
225 * Loop over all the MSI devices until we find one that has an
226 * available interrupt.
227 */
228 list_for_each_entry(msi_data, &msi_head, list) {
229 /*
230 * If the PCI node has an fsl,msi property, then we
231 * restrict our search to the corresponding MSI node.
232 * The simplest way is to skip over MSI nodes with the
233 * wrong phandle. Under the Freescale hypervisor, this
234 * has the additional benefit of skipping over MSI
235 * nodes that are not mapped in the PAMU.
236 */
237 if (phandle && (phandle != msi_data->phandle))
238 continue;
239
240 hwirq = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
241 if (hwirq >= 0)
242 break;
243 }
244
245 if (hwirq < 0) {
246 rc = hwirq;
247 dev_err(&pdev->dev, "could not allocate MSI interrupt\n");
248 goto out_free;
249 }
250
251 virq = irq_create_mapping(msi_data->irqhost, hwirq);
252
253 if (virq == NO_IRQ) {
254 dev_err(&pdev->dev, "fail mapping hwirq %i\n", hwirq);
255 msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
256 rc = -ENOSPC;
257 goto out_free;
258 }
259 /* chip_data is msi_data via host->hostdata in host->map() */
260 irq_set_msi_desc(virq, entry);
261
262 fsl_compose_msi_msg(pdev, hwirq, &msg, msi_data);
263 pci_write_msi_msg(virq, &msg);
264 }
265 return 0;
266
267 out_free:
268 /* free by the caller of this function */
269 return rc;
270 }
271
272 static irqreturn_t fsl_msi_cascade(int irq, void *data)
273 {
274 unsigned int cascade_irq;
275 struct fsl_msi *msi_data;
276 int msir_index = -1;
277 u32 msir_value = 0;
278 u32 intr_index;
279 u32 have_shift = 0;
280 struct fsl_msi_cascade_data *cascade_data = data;
281 irqreturn_t ret = IRQ_NONE;
282
283 msi_data = cascade_data->msi_data;
284
285 msir_index = cascade_data->index;
286
287 if (msir_index >= NR_MSI_REG_MAX)
288 cascade_irq = NO_IRQ;
289
290 switch (msi_data->feature & FSL_PIC_IP_MASK) {
291 case FSL_PIC_IP_MPIC:
292 msir_value = fsl_msi_read(msi_data->msi_regs,
293 msir_index * 0x10);
294 break;
295 case FSL_PIC_IP_IPIC:
296 msir_value = fsl_msi_read(msi_data->msi_regs, msir_index * 0x4);
297 break;
298 #ifdef CONFIG_EPAPR_PARAVIRT
299 case FSL_PIC_IP_VMPIC: {
300 unsigned int ret;
301 ret = fh_vmpic_get_msir(virq_to_hw(irq), &msir_value);
302 if (ret) {
303 pr_err("fsl-msi: fh_vmpic_get_msir() failed for "
304 "irq %u (ret=%u)\n", irq, ret);
305 msir_value = 0;
306 }
307 break;
308 }
309 #endif
310 }
311
312 while (msir_value) {
313 intr_index = ffs(msir_value) - 1;
314
315 cascade_irq = irq_linear_revmap(msi_data->irqhost,
316 msi_hwirq(msi_data, msir_index,
317 intr_index + have_shift));
318 if (cascade_irq != NO_IRQ) {
319 generic_handle_irq(cascade_irq);
320 ret = IRQ_HANDLED;
321 }
322 have_shift += intr_index + 1;
323 msir_value = msir_value >> (intr_index + 1);
324 }
325
326 return ret;
327 }
328
329 static int fsl_of_msi_remove(struct platform_device *ofdev)
330 {
331 struct fsl_msi *msi = platform_get_drvdata(ofdev);
332 int virq, i;
333
334 if (msi->list.prev != NULL)
335 list_del(&msi->list);
336 for (i = 0; i < NR_MSI_REG_MAX; i++) {
337 if (msi->cascade_array[i]) {
338 virq = msi->cascade_array[i]->virq;
339
340 BUG_ON(virq == NO_IRQ);
341
342 free_irq(virq, msi->cascade_array[i]);
343 kfree(msi->cascade_array[i]);
344 irq_dispose_mapping(virq);
345 }
346 }
347 if (msi->bitmap.bitmap)
348 msi_bitmap_free(&msi->bitmap);
349 if ((msi->feature & FSL_PIC_IP_MASK) != FSL_PIC_IP_VMPIC)
350 iounmap(msi->msi_regs);
351 kfree(msi);
352
353 return 0;
354 }
355
356 static struct lock_class_key fsl_msi_irq_class;
357
358 static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev,
359 int offset, int irq_index)
360 {
361 struct fsl_msi_cascade_data *cascade_data = NULL;
362 int virt_msir, i, ret;
363
364 virt_msir = irq_of_parse_and_map(dev->dev.of_node, irq_index);
365 if (virt_msir == NO_IRQ) {
366 dev_err(&dev->dev, "%s: Cannot translate IRQ index %d\n",
367 __func__, irq_index);
368 return 0;
369 }
370
371 cascade_data = kzalloc(sizeof(struct fsl_msi_cascade_data), GFP_KERNEL);
372 if (!cascade_data) {
373 dev_err(&dev->dev, "No memory for MSI cascade data\n");
374 return -ENOMEM;
375 }
376 irq_set_lockdep_class(virt_msir, &fsl_msi_irq_class);
377 cascade_data->index = offset;
378 cascade_data->msi_data = msi;
379 cascade_data->virq = virt_msir;
380 msi->cascade_array[irq_index] = cascade_data;
381
382 ret = request_irq(virt_msir, fsl_msi_cascade, IRQF_NO_THREAD,
383 "fsl-msi-cascade", cascade_data);
384 if (ret) {
385 dev_err(&dev->dev, "failed to request_irq(%d), ret = %d\n",
386 virt_msir, ret);
387 return ret;
388 }
389
390 /* Release the hwirqs corresponding to this MSI register */
391 for (i = 0; i < IRQS_PER_MSI_REG; i++)
392 msi_bitmap_free_hwirqs(&msi->bitmap,
393 msi_hwirq(msi, offset, i), 1);
394
395 return 0;
396 }
397
398 static const struct of_device_id fsl_of_msi_ids[];
399 static int fsl_of_msi_probe(struct platform_device *dev)
400 {
401 const struct of_device_id *match;
402 struct fsl_msi *msi;
403 struct resource res, msiir;
404 int err, i, j, irq_index, count;
405 const u32 *p;
406 const struct fsl_msi_feature *features;
407 int len;
408 u32 offset;
409 struct pci_controller *phb;
410
411 match = of_match_device(fsl_of_msi_ids, &dev->dev);
412 if (!match)
413 return -EINVAL;
414 features = match->data;
415
416 printk(KERN_DEBUG "Setting up Freescale MSI support\n");
417
418 msi = kzalloc(sizeof(struct fsl_msi), GFP_KERNEL);
419 if (!msi) {
420 dev_err(&dev->dev, "No memory for MSI structure\n");
421 return -ENOMEM;
422 }
423 platform_set_drvdata(dev, msi);
424
425 msi->irqhost = irq_domain_add_linear(dev->dev.of_node,
426 NR_MSI_IRQS_MAX, &fsl_msi_host_ops, msi);
427
428 if (msi->irqhost == NULL) {
429 dev_err(&dev->dev, "No memory for MSI irqhost\n");
430 err = -ENOMEM;
431 goto error_out;
432 }
433
434 /*
435 * Under the Freescale hypervisor, the msi nodes don't have a 'reg'
436 * property. Instead, we use hypercalls to access the MSI.
437 */
438 if ((features->fsl_pic_ip & FSL_PIC_IP_MASK) != FSL_PIC_IP_VMPIC) {
439 err = of_address_to_resource(dev->dev.of_node, 0, &res);
440 if (err) {
441 dev_err(&dev->dev, "invalid resource for node %s\n",
442 dev->dev.of_node->full_name);
443 goto error_out;
444 }
445
446 msi->msi_regs = ioremap(res.start, resource_size(&res));
447 if (!msi->msi_regs) {
448 err = -ENOMEM;
449 dev_err(&dev->dev, "could not map node %s\n",
450 dev->dev.of_node->full_name);
451 goto error_out;
452 }
453 msi->msiir_offset =
454 features->msiir_offset + (res.start & 0xfffff);
455
456 /*
457 * First read the MSIIR/MSIIR1 offset from dts
458 * On failure use the hardcode MSIIR offset
459 */
460 if (of_address_to_resource(dev->dev.of_node, 1, &msiir))
461 msi->msiir_offset = features->msiir_offset +
462 (res.start & MSIIR_OFFSET_MASK);
463 else
464 msi->msiir_offset = msiir.start & MSIIR_OFFSET_MASK;
465 }
466
467 msi->feature = features->fsl_pic_ip;
468
469 /* For erratum PIC1 on MPIC version 2.0*/
470 if ((features->fsl_pic_ip & FSL_PIC_IP_MASK) == FSL_PIC_IP_MPIC
471 && (fsl_mpic_primary_get_version() == 0x0200))
472 msi->feature |= MSI_HW_ERRATA_ENDIAN;
473
474 /*
475 * Remember the phandle, so that we can match with any PCI nodes
476 * that have an "fsl,msi" property.
477 */
478 msi->phandle = dev->dev.of_node->phandle;
479
480 err = fsl_msi_init_allocator(msi);
481 if (err) {
482 dev_err(&dev->dev, "Error allocating MSI bitmap\n");
483 goto error_out;
484 }
485
486 p = of_get_property(dev->dev.of_node, "msi-available-ranges", &len);
487
488 if (of_device_is_compatible(dev->dev.of_node, "fsl,mpic-msi-v4.3") ||
489 of_device_is_compatible(dev->dev.of_node, "fsl,vmpic-msi-v4.3")) {
490 msi->srs_shift = MSIIR1_SRS_SHIFT;
491 msi->ibs_shift = MSIIR1_IBS_SHIFT;
492 if (p)
493 dev_warn(&dev->dev, "%s: dose not support msi-available-ranges property\n",
494 __func__);
495
496 for (irq_index = 0; irq_index < NR_MSI_REG_MSIIR1;
497 irq_index++) {
498 err = fsl_msi_setup_hwirq(msi, dev,
499 irq_index, irq_index);
500 if (err)
501 goto error_out;
502 }
503 } else {
504 static const u32 all_avail[] =
505 { 0, NR_MSI_REG_MSIIR * IRQS_PER_MSI_REG };
506
507 msi->srs_shift = MSIIR_SRS_SHIFT;
508 msi->ibs_shift = MSIIR_IBS_SHIFT;
509
510 if (p && len % (2 * sizeof(u32)) != 0) {
511 dev_err(&dev->dev, "%s: Malformed msi-available-ranges property\n",
512 __func__);
513 err = -EINVAL;
514 goto error_out;
515 }
516
517 if (!p) {
518 p = all_avail;
519 len = sizeof(all_avail);
520 }
521
522 for (irq_index = 0, i = 0; i < len / (2 * sizeof(u32)); i++) {
523 if (p[i * 2] % IRQS_PER_MSI_REG ||
524 p[i * 2 + 1] % IRQS_PER_MSI_REG) {
525 pr_warn("%s: %s: msi available range of %u at %u is not IRQ-aligned\n",
526 __func__, dev->dev.of_node->full_name,
527 p[i * 2 + 1], p[i * 2]);
528 err = -EINVAL;
529 goto error_out;
530 }
531
532 offset = p[i * 2] / IRQS_PER_MSI_REG;
533 count = p[i * 2 + 1] / IRQS_PER_MSI_REG;
534
535 for (j = 0; j < count; j++, irq_index++) {
536 err = fsl_msi_setup_hwirq(msi, dev, offset + j,
537 irq_index);
538 if (err)
539 goto error_out;
540 }
541 }
542 }
543
544 list_add_tail(&msi->list, &msi_head);
545
546 /*
547 * Apply the MSI ops to all the controllers.
548 * It doesn't hurt to reassign the same ops,
549 * but bail out if we find another MSI driver.
550 */
551 list_for_each_entry(phb, &hose_list, list_node) {
552 if (!phb->controller_ops.setup_msi_irqs) {
553 phb->controller_ops.setup_msi_irqs = fsl_setup_msi_irqs;
554 phb->controller_ops.teardown_msi_irqs = fsl_teardown_msi_irqs;
555 } else if (phb->controller_ops.setup_msi_irqs != fsl_setup_msi_irqs) {
556 dev_err(&dev->dev, "Different MSI driver already installed!\n");
557 err = -ENODEV;
558 goto error_out;
559 }
560 }
561 return 0;
562 error_out:
563 fsl_of_msi_remove(dev);
564 return err;
565 }
566
567 static const struct fsl_msi_feature mpic_msi_feature = {
568 .fsl_pic_ip = FSL_PIC_IP_MPIC,
569 .msiir_offset = 0x140,
570 };
571
572 static const struct fsl_msi_feature ipic_msi_feature = {
573 .fsl_pic_ip = FSL_PIC_IP_IPIC,
574 .msiir_offset = 0x38,
575 };
576
577 static const struct fsl_msi_feature vmpic_msi_feature = {
578 .fsl_pic_ip = FSL_PIC_IP_VMPIC,
579 .msiir_offset = 0,
580 };
581
582 static const struct of_device_id fsl_of_msi_ids[] = {
583 {
584 .compatible = "fsl,mpic-msi",
585 .data = &mpic_msi_feature,
586 },
587 {
588 .compatible = "fsl,mpic-msi-v4.3",
589 .data = &mpic_msi_feature,
590 },
591 {
592 .compatible = "fsl,ipic-msi",
593 .data = &ipic_msi_feature,
594 },
595 #ifdef CONFIG_EPAPR_PARAVIRT
596 {
597 .compatible = "fsl,vmpic-msi",
598 .data = &vmpic_msi_feature,
599 },
600 {
601 .compatible = "fsl,vmpic-msi-v4.3",
602 .data = &vmpic_msi_feature,
603 },
604 #endif
605 {}
606 };
607
608 static struct platform_driver fsl_of_msi_driver = {
609 .driver = {
610 .name = "fsl-msi",
611 .of_match_table = fsl_of_msi_ids,
612 },
613 .probe = fsl_of_msi_probe,
614 .remove = fsl_of_msi_remove,
615 };
616
617 static __init int fsl_of_msi_init(void)
618 {
619 return platform_driver_register(&fsl_of_msi_driver);
620 }
621
622 subsys_initcall(fsl_of_msi_init);
623
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