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

source code of linux/arch/powerpc/sysdev/fsl_msi.c