arch/powerpc/sysdev/fsl_msi.c

   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/bootmem.h>
  17 #include <linux/msi.h>
  18 #include <linux/pci.h>
  19 #include <linux/slab.h>
  20 #include <linux/of_platform.h>
  21 #include <sysdev/fsl_soc.h>
  22 #include <asm/prom.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 LIST_HEAD(msi_head);
  32
  33 struct fsl_msi_feature {
  34         u32 fsl_pic_ip;
  35         u32 msiir_offset; /* Offset of MSIIR, relative to start of MSIR bank */
  36 };
  37
  38 struct fsl_msi_cascade_data {
  39         struct fsl_msi *msi_data;
  40         int index;
  41 };
  42
  43 static inline u32 fsl_msi_read(u32 __iomem *base, unsigned int reg)
  44 {
  45         return in_be32(base + (reg >> 2));
  46 }
  47
  48 /*
  49  * We do not need this actually. The MSIR register has been read once
  50  * in the cascade interrupt. So, this MSI interrupt has been acked
  51 */
  52 static void fsl_msi_end_irq(struct irq_data *d)
  53 {
  54 }
  55
  56 static struct irq_chip fsl_msi_chip = {
  57         .irq_mask       = mask_msi_irq,
  58         .irq_unmask     = unmask_msi_irq,
  59         .irq_ack        = fsl_msi_end_irq,
  60         .name           = "FSL-MSI",
  61 };
  62
  63 static int fsl_msi_host_map(struct irq_host *h, unsigned int virq,
  64                                 irq_hw_number_t hw)
  65 {
  66         struct fsl_msi *msi_data = h->host_data;
  67         struct irq_chip *chip = &fsl_msi_chip;
  68
  69         irq_set_status_flags(virq, IRQ_TYPE_EDGE_FALLING);
  70
  71         irq_set_chip_data(virq, msi_data);
  72         irq_set_chip_and_handler(virq, chip, handle_edge_irq);
  73
  74         return 0;
  75 }
  76
  77 static struct irq_host_ops fsl_msi_host_ops = {
  78         .map = fsl_msi_host_map,
  79 };
  80
  81 static int fsl_msi_init_allocator(struct fsl_msi *msi_data)
  82 {
  83         int rc;
  84
  85         rc = msi_bitmap_alloc(&msi_data->bitmap, NR_MSI_IRQS,
  86                               msi_data->irqhost->of_node);
  87         if (rc)
  88                 return rc;
  89
  90         rc = msi_bitmap_reserve_dt_hwirqs(&msi_data->bitmap);
  91         if (rc < 0) {
  92                 msi_bitmap_free(&msi_data->bitmap);
  93                 return rc;
  94         }
  95
  96         return 0;
  97 }
  98
  99 static int fsl_msi_check_device(struct pci_dev *pdev, int nvec, int type)
 100 {
 101         if (type == PCI_CAP_ID_MSIX)
 102                 pr_debug("fslmsi: MSI-X untested, trying anyway.\n");
 103
 104         return 0;
 105 }
 106
 107 static void fsl_teardown_msi_irqs(struct pci_dev *pdev)
 108 {
 109         struct msi_desc *entry;
 110         struct fsl_msi *msi_data;
 111
 112         list_for_each_entry(entry, &pdev->msi_list, list) {
 113                 if (entry->irq == NO_IRQ)
 114                         continue;
 115                 msi_data = irq_get_chip_data(entry->irq);
 116                 irq_set_msi_desc(entry->irq, NULL);
 117                 msi_bitmap_free_hwirqs(&msi_data->bitmap,
 118                                        virq_to_hw(entry->irq), 1);
 119                 irq_dispose_mapping(entry->irq);
 120         }
 121
 122         return;
 123 }
 124
 125 static void fsl_compose_msi_msg(struct pci_dev *pdev, int hwirq,
 126                                 struct msi_msg *msg,
 127                                 struct fsl_msi *fsl_msi_data)
 128 {
 129         struct fsl_msi *msi_data = fsl_msi_data;
 130         struct pci_controller *hose = pci_bus_to_host(pdev->bus);
 131         u64 address; /* Physical address of the MSIIR */
 132         int len;
 133         const u64 *reg;
 134
 135         /* If the msi-address-64 property exists, then use it */
 136         reg = of_get_property(hose->dn, "msi-address-64", &len);
 137         if (reg && (len == sizeof(u64)))
 138                 address = be64_to_cpup(reg);
 139         else
 140                 address = fsl_pci_immrbar_base(hose) + msi_data->msiir_offset;
 141
 142         msg->address_lo = lower_32_bits(address);
 143         msg->address_hi = upper_32_bits(address);
 144
 145         msg->data = hwirq;
 146
 147         pr_debug("%s: allocated srs: %d, ibs: %d\n",
 148                 __func__, hwirq / IRQS_PER_MSI_REG, hwirq % IRQS_PER_MSI_REG);
 149 }
 150
 151 static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
 152 {
 153         struct pci_controller *hose = pci_bus_to_host(pdev->bus);
 154         struct device_node *np;
 155         phandle phandle = 0;
 156         int rc, hwirq = -ENOMEM;
 157         unsigned int virq;
 158         struct msi_desc *entry;
 159         struct msi_msg msg;
 160         struct fsl_msi *msi_data;
 161
 162         /*
 163          * If the PCI node has an fsl,msi property, then we need to use it
 164          * to find the specific MSI.
 165          */
 166         np = of_parse_phandle(hose->dn, "fsl,msi", 0);
 167         if (np) {
 168                 if (of_device_is_compatible(np, "fsl,mpic-msi") ||
 169                     of_device_is_compatible(np, "fsl,vmpic-msi"))
 170                         phandle = np->phandle;
 171                 else {
 172                         dev_err(&pdev->dev,
 173                                 "node %s has an invalid fsl,msi phandle %u\n",
 174                                 hose->dn->full_name, np->phandle);
 175                         return -EINVAL;
 176                 }
 177         }
 178
 179         list_for_each_entry(entry, &pdev->msi_list, list) {
 180                 /*
 181                  * Loop over all the MSI devices until we find one that has an
 182                  * available interrupt.
 183                  */
 184                 list_for_each_entry(msi_data, &msi_head, list) {
 185                         /*
 186                          * If the PCI node has an fsl,msi property, then we
 187                          * restrict our search to the corresponding MSI node.
 188                          * The simplest way is to skip over MSI nodes with the
 189                          * wrong phandle. Under the Freescale hypervisor, this
 190                          * has the additional benefit of skipping over MSI
 191                          * nodes that are not mapped in the PAMU.
 192                          */
 193                         if (phandle && (phandle != msi_data->phandle))
 194                                 continue;
 195
 196                         hwirq = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
 197                         if (hwirq >= 0)
 198                                 break;
 199                 }
 200
 201                 if (hwirq < 0) {
 202                         rc = hwirq;
 203                         dev_err(&pdev->dev, "could not allocate MSI interrupt\n");
 204                         goto out_free;
 205                 }
 206
 207                 virq = irq_create_mapping(msi_data->irqhost, hwirq);
 208
 209                 if (virq == NO_IRQ) {
 210                         dev_err(&pdev->dev, "fail mapping hwirq %i\n", hwirq);
 211                         msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
 212                         rc = -ENOSPC;
 213                         goto out_free;
 214                 }
 215                 /* chip_data is msi_data via host->hostdata in host->map() */
 216                 irq_set_msi_desc(virq, entry);
 217
 218                 fsl_compose_msi_msg(pdev, hwirq, &msg, msi_data);
 219                 write_msi_msg(virq, &msg);
 220         }
 221         return 0;
 222
 223 out_free:
 224         /* free by the caller of this function */
 225         return rc;
 226 }
 227
 228 static void fsl_msi_cascade(unsigned int irq, struct irq_desc *desc)
 229 {
 230         struct irq_chip *chip = irq_desc_get_chip(desc);
 231         struct irq_data *idata = irq_desc_get_irq_data(desc);
 232         unsigned int cascade_irq;
 233         struct fsl_msi *msi_data;
 234         int msir_index = -1;
 235         u32 msir_value = 0;
 236         u32 intr_index;
 237         u32 have_shift = 0;
 238         struct fsl_msi_cascade_data *cascade_data;
 239         unsigned int ret;
 240
 241         cascade_data = irq_get_handler_data(irq);
 242         msi_data = cascade_data->msi_data;
 243
 244         raw_spin_lock(&desc->lock);
 245         if ((msi_data->feature &  FSL_PIC_IP_MASK) == FSL_PIC_IP_IPIC) {
 246                 if (chip->irq_mask_ack)
 247                         chip->irq_mask_ack(idata);
 248                 else {
 249                         chip->irq_mask(idata);
 250                         chip->irq_ack(idata);
 251                 }
 252         }
 253
 254         if (unlikely(irqd_irq_inprogress(idata)))
 255                 goto unlock;
 256
 257         msir_index = cascade_data->index;
 258
 259         if (msir_index >= NR_MSI_REG)
 260                 cascade_irq = NO_IRQ;
 261
 262         irqd_set_chained_irq_inprogress(idata);
 263         switch (msi_data->feature & FSL_PIC_IP_MASK) {
 264         case FSL_PIC_IP_MPIC:
 265                 msir_value = fsl_msi_read(msi_data->msi_regs,
 266                         msir_index * 0x10);
 267                 break;
 268         case FSL_PIC_IP_IPIC:
 269                 msir_value = fsl_msi_read(msi_data->msi_regs, msir_index * 0x4);
 270                 break;
 271         case FSL_PIC_IP_VMPIC:
 272                 ret = fh_vmpic_get_msir(virq_to_hw(irq), &msir_value);
 273                 if (ret) {
 274                         pr_err("fsl-msi: fh_vmpic_get_msir() failed for "
 275                                "irq %u (ret=%u)\n", irq, ret);
 276                         msir_value = 0;
 277                 }
 278                 break;
 279         }
 280
 281         while (msir_value) {
 282                 intr_index = ffs(msir_value) - 1;
 283
 284                 cascade_irq = irq_linear_revmap(msi_data->irqhost,
 285                                 msir_index * IRQS_PER_MSI_REG +
 286                                         intr_index + have_shift);
 287                 if (cascade_irq != NO_IRQ)
 288                         generic_handle_irq(cascade_irq);
 289                 have_shift += intr_index + 1;
 290                 msir_value = msir_value >> (intr_index + 1);
 291         }
 292         irqd_clr_chained_irq_inprogress(idata);
 293
 294         switch (msi_data->feature & FSL_PIC_IP_MASK) {
 295         case FSL_PIC_IP_MPIC:
 296         case FSL_PIC_IP_VMPIC:
 297                 chip->irq_eoi(idata);
 298                 break;
 299         case FSL_PIC_IP_IPIC:
 300                 if (!irqd_irq_disabled(idata) && chip->irq_unmask)
 301                         chip->irq_unmask(idata);
 302                 break;
 303         }
 304 unlock:
 305         raw_spin_unlock(&desc->lock);
 306 }
 307
 308 static int fsl_of_msi_remove(struct platform_device *ofdev)
 309 {
 310         struct fsl_msi *msi = platform_get_drvdata(ofdev);
 311         int virq, i;
 312         struct fsl_msi_cascade_data *cascade_data;
 313
 314         if (msi->list.prev != NULL)
 315                 list_del(&msi->list);
 316         for (i = 0; i < NR_MSI_REG; i++) {
 317                 virq = msi->msi_virqs[i];
 318                 if (virq != NO_IRQ) {
 319                         cascade_data = irq_get_handler_data(virq);
 320                         kfree(cascade_data);
 321                         irq_dispose_mapping(virq);
 322                 }
 323         }
 324         if (msi->bitmap.bitmap)
 325                 msi_bitmap_free(&msi->bitmap);
 326         if ((msi->feature & FSL_PIC_IP_MASK) != FSL_PIC_IP_VMPIC)
 327                 iounmap(msi->msi_regs);
 328         kfree(msi);
 329
 330         return 0;
 331 }
 332
 333 static int __devinit fsl_msi_setup_hwirq(struct fsl_msi *msi,
 334                                          struct platform_device *dev,
 335                                          int offset, int irq_index)
 336 {
 337         struct fsl_msi_cascade_data *cascade_data = NULL;
 338         int virt_msir;
 339
 340         virt_msir = irq_of_parse_and_map(dev->dev.of_node, irq_index);
 341         if (virt_msir == NO_IRQ) {
 342                 dev_err(&dev->dev, "%s: Cannot translate IRQ index %d\n",
 343                         __func__, irq_index);
 344                 return 0;
 345         }
 346
 347         cascade_data = kzalloc(sizeof(struct fsl_msi_cascade_data), GFP_KERNEL);
 348         if (!cascade_data) {
 349                 dev_err(&dev->dev, "No memory for MSI cascade data\n");
 350                 return -ENOMEM;
 351         }
 352
 353         msi->msi_virqs[irq_index] = virt_msir;
 354         cascade_data->index = offset;
 355         cascade_data->msi_data = msi;
 356         irq_set_handler_data(virt_msir, cascade_data);
 357         irq_set_chained_handler(virt_msir, fsl_msi_cascade);
 358
 359         return 0;
 360 }
 361
 362 static const struct of_device_id fsl_of_msi_ids[];
 363 static int __devinit fsl_of_msi_probe(struct platform_device *dev)
 364 {
 365         const struct of_device_id *match;
 366         struct fsl_msi *msi;
 367         struct resource res;
 368         int err, i, j, irq_index, count;
 369         int rc;
 370         const u32 *p;
 371         struct fsl_msi_feature *features;
 372         int len;
 373         u32 offset;
 374         static const u32 all_avail[] = { 0, NR_MSI_IRQS };
 375
 376         match = of_match_device(fsl_of_msi_ids, &dev->dev);
 377         if (!match)
 378                 return -EINVAL;
 379         features = match->data;
 380
 381         printk(KERN_DEBUG "Setting up Freescale MSI support\n");
 382
 383         msi = kzalloc(sizeof(struct fsl_msi), GFP_KERNEL);
 384         if (!msi) {
 385                 dev_err(&dev->dev, "No memory for MSI structure\n");
 386                 return -ENOMEM;
 387         }
 388         platform_set_drvdata(dev, msi);
 389
 390         msi->irqhost = irq_alloc_host(dev->dev.of_node, IRQ_HOST_MAP_LINEAR,
 391                                       NR_MSI_IRQS, &fsl_msi_host_ops, 0);
 392
 393         if (msi->irqhost == NULL) {
 394                 dev_err(&dev->dev, "No memory for MSI irqhost\n");
 395                 err = -ENOMEM;
 396                 goto error_out;
 397         }
 398
 399         /*
 400          * Under the Freescale hypervisor, the msi nodes don't have a 'reg'
 401          * property.  Instead, we use hypercalls to access the MSI.
 402          */
 403         if ((features->fsl_pic_ip & FSL_PIC_IP_MASK) != FSL_PIC_IP_VMPIC) {
 404                 err = of_address_to_resource(dev->dev.of_node, 0, &res);
 405                 if (err) {
 406                         dev_err(&dev->dev, "invalid resource for node %s\n",
 407                                 dev->dev.of_node->full_name);
 408                         goto error_out;
 409                 }
 410
 411                 msi->msi_regs = ioremap(res.start, resource_size(&res));
 412                 if (!msi->msi_regs) {
 413                         dev_err(&dev->dev, "could not map node %s\n",
 414                                 dev->dev.of_node->full_name);
 415                         goto error_out;
 416                 }
 417                 msi->msiir_offset =
 418                         features->msiir_offset + (res.start & 0xfffff);
 419         }
 420
 421         msi->feature = features->fsl_pic_ip;
 422
 423         msi->irqhost->host_data = msi;
 424
 425         /*
 426          * Remember the phandle, so that we can match with any PCI nodes
 427          * that have an "fsl,msi" property.
 428          */
 429         msi->phandle = dev->dev.of_node->phandle;
 430
 431         rc = fsl_msi_init_allocator(msi);
 432         if (rc) {
 433                 dev_err(&dev->dev, "Error allocating MSI bitmap\n");
 434                 goto error_out;
 435         }
 436
 437         p = of_get_property(dev->dev.of_node, "msi-available-ranges", &len);
 438         if (p && len % (2 * sizeof(u32)) != 0) {
 439                 dev_err(&dev->dev, "%s: Malformed msi-available-ranges property\n",
 440                         __func__);
 441                 err = -EINVAL;
 442                 goto error_out;
 443         }
 444
 445         if (!p) {
 446                 p = all_avail;
 447                 len = sizeof(all_avail);
 448         }
 449
 450         for (irq_index = 0, i = 0; i < len / (2 * sizeof(u32)); i++) {
 451                 if (p[i * 2] % IRQS_PER_MSI_REG ||
 452                     p[i * 2 + 1] % IRQS_PER_MSI_REG) {
 453                         printk(KERN_WARNING "%s: %s: msi available range of %u at %u is not IRQ-aligned\n",
 454                                __func__, dev->dev.of_node->full_name,
 455                                p[i * 2 + 1], p[i * 2]);
 456                         err = -EINVAL;
 457                         goto error_out;
 458                 }
 459
 460                 offset = p[i * 2] / IRQS_PER_MSI_REG;
 461                 count = p[i * 2 + 1] / IRQS_PER_MSI_REG;
 462
 463                 for (j = 0; j < count; j++, irq_index++) {
 464                         err = fsl_msi_setup_hwirq(msi, dev, offset + j, irq_index);
 465                         if (err)
 466                                 goto error_out;
 467                 }
 468         }
 469
 470         list_add_tail(&msi->list, &msi_head);
 471
 472         /* The multiple setting ppc_md.setup_msi_irqs will not harm things */
 473         if (!ppc_md.setup_msi_irqs) {
 474                 ppc_md.setup_msi_irqs = fsl_setup_msi_irqs;
 475                 ppc_md.teardown_msi_irqs = fsl_teardown_msi_irqs;
 476                 ppc_md.msi_check_device = fsl_msi_check_device;
 477         } else if (ppc_md.setup_msi_irqs != fsl_setup_msi_irqs) {
 478                 dev_err(&dev->dev, "Different MSI driver already installed!\n");
 479                 err = -ENODEV;
 480                 goto error_out;
 481         }
 482         return 0;
 483 error_out:
 484         fsl_of_msi_remove(dev);
 485         return err;
 486 }
 487
 488 static const struct fsl_msi_feature mpic_msi_feature = {
 489         .fsl_pic_ip = FSL_PIC_IP_MPIC,
 490         .msiir_offset = 0x140,
 491 };
 492
 493 static const struct fsl_msi_feature ipic_msi_feature = {
 494         .fsl_pic_ip = FSL_PIC_IP_IPIC,
 495         .msiir_offset = 0x38,
 496 };
 497
 498 static const struct fsl_msi_feature vmpic_msi_feature = {
 499         .fsl_pic_ip = FSL_PIC_IP_VMPIC,
 500         .msiir_offset = 0,
 501 };
 502
 503 static const struct of_device_id fsl_of_msi_ids[] = {
 504         {
 505                 .compatible = "fsl,mpic-msi",
 506                 .data = (void *)&mpic_msi_feature,
 507         },
 508         {
 509                 .compatible = "fsl,ipic-msi",
 510                 .data = (void *)&ipic_msi_feature,
 511         },
 512         {
 513                 .compatible = "fsl,vmpic-msi",
 514                 .data = (void *)&vmpic_msi_feature,
 515         },
 516         {}
 517 };
 518
 519 static struct platform_driver fsl_of_msi_driver = {
 520         .driver = {
 521                 .name = "fsl-msi",
 522                 .owner = THIS_MODULE,
 523                 .of_match_table = fsl_of_msi_ids,
 524         },
 525         .probe = fsl_of_msi_probe,
 526         .remove = fsl_of_msi_remove,
 527 };
 528
 529 static __init int fsl_of_msi_init(void)
 530 {
 531         return platform_driver_register(&fsl_of_msi_driver);
 532 }
 533
 534 subsys_initcall(fsl_of_msi_init);