treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / arch / powerpc / sysdev / fsl_msi.c
blob808e7118abfc5b45655156866e967a5be72030d5
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2007-2011 Freescale Semiconductor, Inc.
5 * Author: Tony Li <tony.li@freescale.com>
6 * Jason Jin <Jason.jin@freescale.com>
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_platform.h>
15 #include <linux/interrupt.h>
16 #include <linux/seq_file.h>
17 #include <sysdev/fsl_soc.h>
18 #include <asm/prom.h>
19 #include <asm/hw_irq.h>
20 #include <asm/ppc-pci.h>
21 #include <asm/mpic.h>
22 #include <asm/fsl_hcalls.h>
24 #include "fsl_msi.h"
25 #include "fsl_pci.h"
27 #define MSIIR_OFFSET_MASK 0xfffff
28 #define MSIIR_IBS_SHIFT 0
29 #define MSIIR_SRS_SHIFT 5
30 #define MSIIR1_IBS_SHIFT 4
31 #define MSIIR1_SRS_SHIFT 0
32 #define MSI_SRS_MASK 0xf
33 #define MSI_IBS_MASK 0x1f
35 #define msi_hwirq(msi, msir_index, intr_index) \
36 ((msir_index) << (msi)->srs_shift | \
37 ((intr_index) << (msi)->ibs_shift))
39 static LIST_HEAD(msi_head);
41 struct fsl_msi_feature {
42 u32 fsl_pic_ip;
43 u32 msiir_offset; /* Offset of MSIIR, relative to start of MSIR bank */
46 struct fsl_msi_cascade_data {
47 struct fsl_msi *msi_data;
48 int index;
49 int virq;
52 static inline u32 fsl_msi_read(u32 __iomem *base, unsigned int reg)
54 return in_be32(base + (reg >> 2));
58 * We do not need this actually. The MSIR register has been read once
59 * in the cascade interrupt. So, this MSI interrupt has been acked
61 static void fsl_msi_end_irq(struct irq_data *d)
65 static void fsl_msi_print_chip(struct irq_data *irqd, struct seq_file *p)
67 struct fsl_msi *msi_data = irqd->domain->host_data;
68 irq_hw_number_t hwirq = irqd_to_hwirq(irqd);
69 int cascade_virq, srs;
71 srs = (hwirq >> msi_data->srs_shift) & MSI_SRS_MASK;
72 cascade_virq = msi_data->cascade_array[srs]->virq;
74 seq_printf(p, " fsl-msi-%d", cascade_virq);
78 static struct irq_chip fsl_msi_chip = {
79 .irq_mask = pci_msi_mask_irq,
80 .irq_unmask = pci_msi_unmask_irq,
81 .irq_ack = fsl_msi_end_irq,
82 .irq_print_chip = fsl_msi_print_chip,
85 static int fsl_msi_host_map(struct irq_domain *h, unsigned int virq,
86 irq_hw_number_t hw)
88 struct fsl_msi *msi_data = h->host_data;
89 struct irq_chip *chip = &fsl_msi_chip;
91 irq_set_status_flags(virq, IRQ_TYPE_EDGE_FALLING);
93 irq_set_chip_data(virq, msi_data);
94 irq_set_chip_and_handler(virq, chip, handle_edge_irq);
96 return 0;
99 static const struct irq_domain_ops fsl_msi_host_ops = {
100 .map = fsl_msi_host_map,
103 static int fsl_msi_init_allocator(struct fsl_msi *msi_data)
105 int rc, hwirq;
107 rc = msi_bitmap_alloc(&msi_data->bitmap, NR_MSI_IRQS_MAX,
108 irq_domain_get_of_node(msi_data->irqhost));
109 if (rc)
110 return rc;
113 * Reserve all the hwirqs
114 * The available hwirqs will be released in fsl_msi_setup_hwirq()
116 for (hwirq = 0; hwirq < NR_MSI_IRQS_MAX; hwirq++)
117 msi_bitmap_reserve_hwirq(&msi_data->bitmap, hwirq);
119 return 0;
122 static void fsl_teardown_msi_irqs(struct pci_dev *pdev)
124 struct msi_desc *entry;
125 struct fsl_msi *msi_data;
126 irq_hw_number_t hwirq;
128 for_each_pci_msi_entry(entry, pdev) {
129 if (!entry->irq)
130 continue;
131 hwirq = virq_to_hw(entry->irq);
132 msi_data = irq_get_chip_data(entry->irq);
133 irq_set_msi_desc(entry->irq, NULL);
134 irq_dispose_mapping(entry->irq);
135 msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
138 return;
141 static void fsl_compose_msi_msg(struct pci_dev *pdev, int hwirq,
142 struct msi_msg *msg,
143 struct fsl_msi *fsl_msi_data)
145 struct fsl_msi *msi_data = fsl_msi_data;
146 struct pci_controller *hose = pci_bus_to_host(pdev->bus);
147 u64 address; /* Physical address of the MSIIR */
148 int len;
149 const __be64 *reg;
151 /* If the msi-address-64 property exists, then use it */
152 reg = of_get_property(hose->dn, "msi-address-64", &len);
153 if (reg && (len == sizeof(u64)))
154 address = be64_to_cpup(reg);
155 else
156 address = fsl_pci_immrbar_base(hose) + msi_data->msiir_offset;
158 msg->address_lo = lower_32_bits(address);
159 msg->address_hi = upper_32_bits(address);
162 * MPIC version 2.0 has erratum PIC1. It causes
163 * that neither MSI nor MSI-X can work fine.
164 * This is a workaround to allow MSI-X to function
165 * properly. It only works for MSI-X, we prevent
166 * MSI on buggy chips in fsl_setup_msi_irqs().
168 if (msi_data->feature & MSI_HW_ERRATA_ENDIAN)
169 msg->data = __swab32(hwirq);
170 else
171 msg->data = hwirq;
173 pr_debug("%s: allocated srs: %d, ibs: %d\n", __func__,
174 (hwirq >> msi_data->srs_shift) & MSI_SRS_MASK,
175 (hwirq >> msi_data->ibs_shift) & MSI_IBS_MASK);
178 static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
180 struct pci_controller *hose = pci_bus_to_host(pdev->bus);
181 struct device_node *np;
182 phandle phandle = 0;
183 int rc, hwirq = -ENOMEM;
184 unsigned int virq;
185 struct msi_desc *entry;
186 struct msi_msg msg;
187 struct fsl_msi *msi_data;
189 if (type == PCI_CAP_ID_MSI) {
191 * MPIC version 2.0 has erratum PIC1. For now MSI
192 * could not work. So check to prevent MSI from
193 * being used on the board with this erratum.
195 list_for_each_entry(msi_data, &msi_head, list)
196 if (msi_data->feature & MSI_HW_ERRATA_ENDIAN)
197 return -EINVAL;
201 * If the PCI node has an fsl,msi property, then we need to use it
202 * to find the specific MSI.
204 np = of_parse_phandle(hose->dn, "fsl,msi", 0);
205 if (np) {
206 if (of_device_is_compatible(np, "fsl,mpic-msi") ||
207 of_device_is_compatible(np, "fsl,vmpic-msi") ||
208 of_device_is_compatible(np, "fsl,vmpic-msi-v4.3"))
209 phandle = np->phandle;
210 else {
211 dev_err(&pdev->dev,
212 "node %pOF has an invalid fsl,msi phandle %u\n",
213 hose->dn, np->phandle);
214 return -EINVAL;
218 for_each_pci_msi_entry(entry, pdev) {
220 * Loop over all the MSI devices until we find one that has an
221 * available interrupt.
223 list_for_each_entry(msi_data, &msi_head, list) {
225 * If the PCI node has an fsl,msi property, then we
226 * restrict our search to the corresponding MSI node.
227 * The simplest way is to skip over MSI nodes with the
228 * wrong phandle. Under the Freescale hypervisor, this
229 * has the additional benefit of skipping over MSI
230 * nodes that are not mapped in the PAMU.
232 if (phandle && (phandle != msi_data->phandle))
233 continue;
235 hwirq = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
236 if (hwirq >= 0)
237 break;
240 if (hwirq < 0) {
241 rc = hwirq;
242 dev_err(&pdev->dev, "could not allocate MSI interrupt\n");
243 goto out_free;
246 virq = irq_create_mapping(msi_data->irqhost, hwirq);
248 if (!virq) {
249 dev_err(&pdev->dev, "fail mapping hwirq %i\n", hwirq);
250 msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
251 rc = -ENOSPC;
252 goto out_free;
254 /* chip_data is msi_data via host->hostdata in host->map() */
255 irq_set_msi_desc(virq, entry);
257 fsl_compose_msi_msg(pdev, hwirq, &msg, msi_data);
258 pci_write_msi_msg(virq, &msg);
260 return 0;
262 out_free:
263 /* free by the caller of this function */
264 return rc;
267 static irqreturn_t fsl_msi_cascade(int irq, void *data)
269 unsigned int cascade_irq;
270 struct fsl_msi *msi_data;
271 int msir_index = -1;
272 u32 msir_value = 0;
273 u32 intr_index;
274 u32 have_shift = 0;
275 struct fsl_msi_cascade_data *cascade_data = data;
276 irqreturn_t ret = IRQ_NONE;
278 msi_data = cascade_data->msi_data;
280 msir_index = cascade_data->index;
282 if (msir_index >= NR_MSI_REG_MAX)
283 cascade_irq = 0;
285 switch (msi_data->feature & FSL_PIC_IP_MASK) {
286 case FSL_PIC_IP_MPIC:
287 msir_value = fsl_msi_read(msi_data->msi_regs,
288 msir_index * 0x10);
289 break;
290 case FSL_PIC_IP_IPIC:
291 msir_value = fsl_msi_read(msi_data->msi_regs, msir_index * 0x4);
292 break;
293 #ifdef CONFIG_EPAPR_PARAVIRT
294 case FSL_PIC_IP_VMPIC: {
295 unsigned int ret;
296 ret = fh_vmpic_get_msir(virq_to_hw(irq), &msir_value);
297 if (ret) {
298 pr_err("fsl-msi: fh_vmpic_get_msir() failed for "
299 "irq %u (ret=%u)\n", irq, ret);
300 msir_value = 0;
302 break;
304 #endif
307 while (msir_value) {
308 intr_index = ffs(msir_value) - 1;
310 cascade_irq = irq_linear_revmap(msi_data->irqhost,
311 msi_hwirq(msi_data, msir_index,
312 intr_index + have_shift));
313 if (cascade_irq) {
314 generic_handle_irq(cascade_irq);
315 ret = IRQ_HANDLED;
317 have_shift += intr_index + 1;
318 msir_value = msir_value >> (intr_index + 1);
321 return ret;
324 static int fsl_of_msi_remove(struct platform_device *ofdev)
326 struct fsl_msi *msi = platform_get_drvdata(ofdev);
327 int virq, i;
329 if (msi->list.prev != NULL)
330 list_del(&msi->list);
331 for (i = 0; i < NR_MSI_REG_MAX; i++) {
332 if (msi->cascade_array[i]) {
333 virq = msi->cascade_array[i]->virq;
335 BUG_ON(!virq);
337 free_irq(virq, msi->cascade_array[i]);
338 kfree(msi->cascade_array[i]);
339 irq_dispose_mapping(virq);
342 if (msi->bitmap.bitmap)
343 msi_bitmap_free(&msi->bitmap);
344 if ((msi->feature & FSL_PIC_IP_MASK) != FSL_PIC_IP_VMPIC)
345 iounmap(msi->msi_regs);
346 kfree(msi);
348 return 0;
351 static struct lock_class_key fsl_msi_irq_class;
352 static struct lock_class_key fsl_msi_irq_request_class;
354 static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev,
355 int offset, int irq_index)
357 struct fsl_msi_cascade_data *cascade_data = NULL;
358 int virt_msir, i, ret;
360 virt_msir = irq_of_parse_and_map(dev->dev.of_node, irq_index);
361 if (!virt_msir) {
362 dev_err(&dev->dev, "%s: Cannot translate IRQ index %d\n",
363 __func__, irq_index);
364 return 0;
367 cascade_data = kzalloc(sizeof(struct fsl_msi_cascade_data), GFP_KERNEL);
368 if (!cascade_data) {
369 dev_err(&dev->dev, "No memory for MSI cascade data\n");
370 return -ENOMEM;
372 irq_set_lockdep_class(virt_msir, &fsl_msi_irq_class,
373 &fsl_msi_irq_request_class);
374 cascade_data->index = offset;
375 cascade_data->msi_data = msi;
376 cascade_data->virq = virt_msir;
377 msi->cascade_array[irq_index] = cascade_data;
379 ret = request_irq(virt_msir, fsl_msi_cascade, IRQF_NO_THREAD,
380 "fsl-msi-cascade", cascade_data);
381 if (ret) {
382 dev_err(&dev->dev, "failed to request_irq(%d), ret = %d\n",
383 virt_msir, ret);
384 return ret;
387 /* Release the hwirqs corresponding to this MSI register */
388 for (i = 0; i < IRQS_PER_MSI_REG; i++)
389 msi_bitmap_free_hwirqs(&msi->bitmap,
390 msi_hwirq(msi, offset, i), 1);
392 return 0;
395 static const struct of_device_id fsl_of_msi_ids[];
396 static int fsl_of_msi_probe(struct platform_device *dev)
398 const struct of_device_id *match;
399 struct fsl_msi *msi;
400 struct resource res, msiir;
401 int err, i, j, irq_index, count;
402 const u32 *p;
403 const struct fsl_msi_feature *features;
404 int len;
405 u32 offset;
406 struct pci_controller *phb;
408 match = of_match_device(fsl_of_msi_ids, &dev->dev);
409 if (!match)
410 return -EINVAL;
411 features = match->data;
413 printk(KERN_DEBUG "Setting up Freescale MSI support\n");
415 msi = kzalloc(sizeof(struct fsl_msi), GFP_KERNEL);
416 if (!msi) {
417 dev_err(&dev->dev, "No memory for MSI structure\n");
418 return -ENOMEM;
420 platform_set_drvdata(dev, msi);
422 msi->irqhost = irq_domain_add_linear(dev->dev.of_node,
423 NR_MSI_IRQS_MAX, &fsl_msi_host_ops, msi);
425 if (msi->irqhost == NULL) {
426 dev_err(&dev->dev, "No memory for MSI irqhost\n");
427 err = -ENOMEM;
428 goto error_out;
432 * Under the Freescale hypervisor, the msi nodes don't have a 'reg'
433 * property. Instead, we use hypercalls to access the MSI.
435 if ((features->fsl_pic_ip & FSL_PIC_IP_MASK) != FSL_PIC_IP_VMPIC) {
436 err = of_address_to_resource(dev->dev.of_node, 0, &res);
437 if (err) {
438 dev_err(&dev->dev, "invalid resource for node %pOF\n",
439 dev->dev.of_node);
440 goto error_out;
443 msi->msi_regs = ioremap(res.start, resource_size(&res));
444 if (!msi->msi_regs) {
445 err = -ENOMEM;
446 dev_err(&dev->dev, "could not map node %pOF\n",
447 dev->dev.of_node);
448 goto error_out;
450 msi->msiir_offset =
451 features->msiir_offset + (res.start & 0xfffff);
454 * First read the MSIIR/MSIIR1 offset from dts
455 * On failure use the hardcode MSIIR offset
457 if (of_address_to_resource(dev->dev.of_node, 1, &msiir))
458 msi->msiir_offset = features->msiir_offset +
459 (res.start & MSIIR_OFFSET_MASK);
460 else
461 msi->msiir_offset = msiir.start & MSIIR_OFFSET_MASK;
464 msi->feature = features->fsl_pic_ip;
466 /* For erratum PIC1 on MPIC version 2.0*/
467 if ((features->fsl_pic_ip & FSL_PIC_IP_MASK) == FSL_PIC_IP_MPIC
468 && (fsl_mpic_primary_get_version() == 0x0200))
469 msi->feature |= MSI_HW_ERRATA_ENDIAN;
472 * Remember the phandle, so that we can match with any PCI nodes
473 * that have an "fsl,msi" property.
475 msi->phandle = dev->dev.of_node->phandle;
477 err = fsl_msi_init_allocator(msi);
478 if (err) {
479 dev_err(&dev->dev, "Error allocating MSI bitmap\n");
480 goto error_out;
483 p = of_get_property(dev->dev.of_node, "msi-available-ranges", &len);
485 if (of_device_is_compatible(dev->dev.of_node, "fsl,mpic-msi-v4.3") ||
486 of_device_is_compatible(dev->dev.of_node, "fsl,vmpic-msi-v4.3")) {
487 msi->srs_shift = MSIIR1_SRS_SHIFT;
488 msi->ibs_shift = MSIIR1_IBS_SHIFT;
489 if (p)
490 dev_warn(&dev->dev, "%s: dose not support msi-available-ranges property\n",
491 __func__);
493 for (irq_index = 0; irq_index < NR_MSI_REG_MSIIR1;
494 irq_index++) {
495 err = fsl_msi_setup_hwirq(msi, dev,
496 irq_index, irq_index);
497 if (err)
498 goto error_out;
500 } else {
501 static const u32 all_avail[] =
502 { 0, NR_MSI_REG_MSIIR * IRQS_PER_MSI_REG };
504 msi->srs_shift = MSIIR_SRS_SHIFT;
505 msi->ibs_shift = MSIIR_IBS_SHIFT;
507 if (p && len % (2 * sizeof(u32)) != 0) {
508 dev_err(&dev->dev, "%s: Malformed msi-available-ranges property\n",
509 __func__);
510 err = -EINVAL;
511 goto error_out;
514 if (!p) {
515 p = all_avail;
516 len = sizeof(all_avail);
519 for (irq_index = 0, i = 0; i < len / (2 * sizeof(u32)); i++) {
520 if (p[i * 2] % IRQS_PER_MSI_REG ||
521 p[i * 2 + 1] % IRQS_PER_MSI_REG) {
522 pr_warn("%s: %pOF: msi available range of %u at %u is not IRQ-aligned\n",
523 __func__, dev->dev.of_node,
524 p[i * 2 + 1], p[i * 2]);
525 err = -EINVAL;
526 goto error_out;
529 offset = p[i * 2] / IRQS_PER_MSI_REG;
530 count = p[i * 2 + 1] / IRQS_PER_MSI_REG;
532 for (j = 0; j < count; j++, irq_index++) {
533 err = fsl_msi_setup_hwirq(msi, dev, offset + j,
534 irq_index);
535 if (err)
536 goto error_out;
541 list_add_tail(&msi->list, &msi_head);
544 * Apply the MSI ops to all the controllers.
545 * It doesn't hurt to reassign the same ops,
546 * but bail out if we find another MSI driver.
548 list_for_each_entry(phb, &hose_list, list_node) {
549 if (!phb->controller_ops.setup_msi_irqs) {
550 phb->controller_ops.setup_msi_irqs = fsl_setup_msi_irqs;
551 phb->controller_ops.teardown_msi_irqs = fsl_teardown_msi_irqs;
552 } else if (phb->controller_ops.setup_msi_irqs != fsl_setup_msi_irqs) {
553 dev_err(&dev->dev, "Different MSI driver already installed!\n");
554 err = -ENODEV;
555 goto error_out;
558 return 0;
559 error_out:
560 fsl_of_msi_remove(dev);
561 return err;
564 static const struct fsl_msi_feature mpic_msi_feature = {
565 .fsl_pic_ip = FSL_PIC_IP_MPIC,
566 .msiir_offset = 0x140,
569 static const struct fsl_msi_feature ipic_msi_feature = {
570 .fsl_pic_ip = FSL_PIC_IP_IPIC,
571 .msiir_offset = 0x38,
574 static const struct fsl_msi_feature vmpic_msi_feature = {
575 .fsl_pic_ip = FSL_PIC_IP_VMPIC,
576 .msiir_offset = 0,
579 static const struct of_device_id fsl_of_msi_ids[] = {
581 .compatible = "fsl,mpic-msi",
582 .data = &mpic_msi_feature,
585 .compatible = "fsl,mpic-msi-v4.3",
586 .data = &mpic_msi_feature,
589 .compatible = "fsl,ipic-msi",
590 .data = &ipic_msi_feature,
592 #ifdef CONFIG_EPAPR_PARAVIRT
594 .compatible = "fsl,vmpic-msi",
595 .data = &vmpic_msi_feature,
598 .compatible = "fsl,vmpic-msi-v4.3",
599 .data = &vmpic_msi_feature,
601 #endif
605 static struct platform_driver fsl_of_msi_driver = {
606 .driver = {
607 .name = "fsl-msi",
608 .of_match_table = fsl_of_msi_ids,
610 .probe = fsl_of_msi_probe,
611 .remove = fsl_of_msi_remove,
614 static __init int fsl_of_msi_init(void)
616 return platform_driver_register(&fsl_of_msi_driver);
619 subsys_initcall(fsl_of_msi_init);