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 "fsl_msi.h"
  27 #include "fsl_pci.h"
  28
  29 LIST_HEAD(msi_head);
  30
  31 struct fsl_msi_feature {
  32         u32 fsl_pic_ip;
  33         u32 msiir_offset;
  34 };
  35
  36 struct fsl_msi_cascade_data {
  37         struct fsl_msi *msi_data;
  38         int index;
  39 };
  40
  41 static inline u32 fsl_msi_read(u32 __iomem *base, unsigned int reg)
  42 {
  43         return in_be32(base + (reg >> 2));
  44 }
  45
  46 /*
  47  * We do not need this actually. The MSIR register has been read once
  48  * in the cascade interrupt. So, this MSI interrupt has been acked
  49 */
  50 static void fsl_msi_end_irq(struct irq_data *d)
  51 {
  52 }
  53
  54 static struct irq_chip fsl_msi_chip = {
  55         .irq_mask       = mask_msi_irq,
  56         .irq_unmask     = unmask_msi_irq,
  57         .irq_ack        = fsl_msi_end_irq,
  58         .name           = "FSL-MSI",
  59 };
  60
  61 static int fsl_msi_host_map(struct irq_host *h, unsigned int virq,
  62                                 irq_hw_number_t hw)
  63 {
  64         struct fsl_msi *msi_data = h->host_data;
  65         struct irq_chip *chip = &fsl_msi_chip;
  66
  67         irq_set_status_flags(virq, IRQ_TYPE_EDGE_FALLING);
  68
  69         irq_set_chip_data(virq, msi_data);
  70         irq_set_chip_and_handler(virq, chip, handle_edge_irq);
  71
  72         return 0;
  73 }
  74
  75 static struct irq_host_ops fsl_msi_host_ops = {
  76         .map = fsl_msi_host_map,
  77 };
  78
  79 static int fsl_msi_init_allocator(struct fsl_msi *msi_data)
  80 {
  81         int rc;
  82
  83         rc = msi_bitmap_alloc(&msi_data->bitmap, NR_MSI_IRQS,
  84                               msi_data->irqhost->of_node);
  85         if (rc)
  86                 return rc;
  87
  88         rc = msi_bitmap_reserve_dt_hwirqs(&msi_data->bitmap);
  89         if (rc < 0) {
  90                 msi_bitmap_free(&msi_data->bitmap);
  91                 return rc;
  92         }
  93
  94         return 0;
  95 }
  96
  97 static int fsl_msi_check_device(struct pci_dev *pdev, int nvec, int type)
  98 {
  99         if (type == PCI_CAP_ID_MSIX)
 100                 pr_debug("fslmsi: MSI-X untested, trying anyway.\n");
 101
 102         return 0;
 103 }
 104
 105 static void fsl_teardown_msi_irqs(struct pci_dev *pdev)
 106 {
 107         struct msi_desc *entry;
 108         struct fsl_msi *msi_data;
 109
 110         list_for_each_entry(entry, &pdev->msi_list, list) {
 111                 if (entry->irq == NO_IRQ)
 112                         continue;
 113                 msi_data = irq_get_chip_data(entry->irq);
 114                 irq_set_msi_desc(entry->irq, NULL);
 115                 msi_bitmap_free_hwirqs(&msi_data->bitmap,
 116                                        virq_to_hw(entry->irq), 1);
 117                 irq_dispose_mapping(entry->irq);
 118         }
 119
 120         return;
 121 }
 122
 123 static void fsl_compose_msi_msg(struct pci_dev *pdev, int hwirq,
 124                                 struct msi_msg *msg,
 125                                 struct fsl_msi *fsl_msi_data)
 126 {
 127         struct fsl_msi *msi_data = fsl_msi_data;
 128         struct pci_controller *hose = pci_bus_to_host(pdev->bus);
 129         u64 base = fsl_pci_immrbar_base(hose);
 130
 131         msg->address_lo = msi_data->msi_addr_lo + lower_32_bits(base);
 132         msg->address_hi = msi_data->msi_addr_hi + upper_32_bits(base);
 133
 134         msg->data = hwirq;
 135
 136         pr_debug("%s: allocated srs: %d, ibs: %d\n",
 137                 __func__, hwirq / IRQS_PER_MSI_REG, hwirq % IRQS_PER_MSI_REG);
 138 }
 139
 140 static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
 141 {
 142         int rc, hwirq = -ENOMEM;
 143         unsigned int virq;
 144         struct msi_desc *entry;
 145         struct msi_msg msg;
 146         struct fsl_msi *msi_data;
 147
 148         list_for_each_entry(entry, &pdev->msi_list, list) {
 149                 list_for_each_entry(msi_data, &msi_head, list) {
 150                         hwirq = msi_bitmap_alloc_hwirqs(&msi_data->bitmap, 1);
 151                         if (hwirq >= 0)
 152                                 break;
 153                 }
 154
 155                 if (hwirq < 0) {
 156                         rc = hwirq;
 157                         pr_debug("%s: fail allocating msi interrupt\n",
 158                                         __func__);
 159                         goto out_free;
 160                 }
 161
 162                 virq = irq_create_mapping(msi_data->irqhost, hwirq);
 163
 164                 if (virq == NO_IRQ) {
 165                         pr_debug("%s: fail mapping hwirq 0x%x\n",
 166                                         __func__, hwirq);
 167                         msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
 168                         rc = -ENOSPC;
 169                         goto out_free;
 170                 }
 171                 /* chip_data is msi_data via host->hostdata in host->map() */
 172                 irq_set_msi_desc(virq, entry);
 173
 174                 fsl_compose_msi_msg(pdev, hwirq, &msg, msi_data);
 175                 write_msi_msg(virq, &msg);
 176         }
 177         return 0;
 178
 179 out_free:
 180         /* free by the caller of this function */
 181         return rc;
 182 }
 183
 184 static void fsl_msi_cascade(unsigned int irq, struct irq_desc *desc)
 185 {
 186         struct irq_chip *chip = irq_desc_get_chip(desc);
 187         struct irq_data *idata = irq_desc_get_irq_data(desc);
 188         unsigned int cascade_irq;
 189         struct fsl_msi *msi_data;
 190         int msir_index = -1;
 191         u32 msir_value = 0;
 192         u32 intr_index;
 193         u32 have_shift = 0;
 194         struct fsl_msi_cascade_data *cascade_data;
 195
 196         cascade_data = irq_get_handler_data(irq);
 197         msi_data = cascade_data->msi_data;
 198
 199         raw_spin_lock(&desc->lock);
 200         if ((msi_data->feature &  FSL_PIC_IP_MASK) == FSL_PIC_IP_IPIC) {
 201                 if (chip->irq_mask_ack)
 202                         chip->irq_mask_ack(idata);
 203                 else {
 204                         chip->irq_mask(idata);
 205                         chip->irq_ack(idata);
 206                 }
 207         }
 208
 209         if (unlikely(irqd_irq_inprogress(idata)))
 210                 goto unlock;
 211
 212         msir_index = cascade_data->index;
 213
 214         if (msir_index >= NR_MSI_REG)
 215                 cascade_irq = NO_IRQ;
 216
 217         irqd_set_chained_irq_inprogress(idata);
 218         switch (msi_data->feature & FSL_PIC_IP_MASK) {
 219         case FSL_PIC_IP_MPIC:
 220                 msir_value = fsl_msi_read(msi_data->msi_regs,
 221                         msir_index * 0x10);
 222                 break;
 223         case FSL_PIC_IP_IPIC:
 224                 msir_value = fsl_msi_read(msi_data->msi_regs, msir_index * 0x4);
 225                 break;
 226         }
 227
 228         while (msir_value) {
 229                 intr_index = ffs(msir_value) - 1;
 230
 231                 cascade_irq = irq_linear_revmap(msi_data->irqhost,
 232                                 msir_index * IRQS_PER_MSI_REG +
 233                                         intr_index + have_shift);
 234                 if (cascade_irq != NO_IRQ)
 235                         generic_handle_irq(cascade_irq);
 236                 have_shift += intr_index + 1;
 237                 msir_value = msir_value >> (intr_index + 1);
 238         }
 239         irqd_clr_chained_irq_inprogress(idata);
 240
 241         switch (msi_data->feature & FSL_PIC_IP_MASK) {
 242         case FSL_PIC_IP_MPIC:
 243                 chip->irq_eoi(idata);
 244                 break;
 245         case FSL_PIC_IP_IPIC:
 246                 if (!irqd_irq_disabled(idata) && chip->irq_unmask)
 247                         chip->irq_unmask(idata);
 248                 break;
 249         }
 250 unlock:
 251         raw_spin_unlock(&desc->lock);
 252 }
 253
 254 static int fsl_of_msi_remove(struct platform_device *ofdev)
 255 {
 256         struct fsl_msi *msi = platform_get_drvdata(ofdev);
 257         int virq, i;
 258         struct fsl_msi_cascade_data *cascade_data;
 259
 260         if (msi->list.prev != NULL)
 261                 list_del(&msi->list);
 262         for (i = 0; i < NR_MSI_REG; i++) {
 263                 virq = msi->msi_virqs[i];
 264                 if (virq != NO_IRQ) {
 265                         cascade_data = irq_get_handler_data(virq);
 266                         kfree(cascade_data);
 267                         irq_dispose_mapping(virq);
 268                 }
 269         }
 270         if (msi->bitmap.bitmap)
 271                 msi_bitmap_free(&msi->bitmap);
 272         iounmap(msi->msi_regs);
 273         kfree(msi);
 274
 275         return 0;
 276 }
 277
 278 static int __devinit fsl_msi_setup_hwirq(struct fsl_msi *msi,
 279                                          struct platform_device *dev,
 280                                          int offset, int irq_index)
 281 {
 282         struct fsl_msi_cascade_data *cascade_data = NULL;
 283         int virt_msir;
 284
 285         virt_msir = irq_of_parse_and_map(dev->dev.of_node, irq_index);
 286         if (virt_msir == NO_IRQ) {
 287                 dev_err(&dev->dev, "%s: Cannot translate IRQ index %d\n",
 288                         __func__, irq_index);
 289                 return 0;
 290         }
 291
 292         cascade_data = kzalloc(sizeof(struct fsl_msi_cascade_data), GFP_KERNEL);
 293         if (!cascade_data) {
 294                 dev_err(&dev->dev, "No memory for MSI cascade data\n");
 295                 return -ENOMEM;
 296         }
 297
 298         msi->msi_virqs[irq_index] = virt_msir;
 299         cascade_data->index = offset + irq_index;
 300         cascade_data->msi_data = msi;
 301         irq_set_handler_data(virt_msir, cascade_data);
 302         irq_set_chained_handler(virt_msir, fsl_msi_cascade);
 303
 304         return 0;
 305 }
 306
 307 static const struct of_device_id fsl_of_msi_ids[];
 308 static int __devinit fsl_of_msi_probe(struct platform_device *dev)
 309 {
 310         const struct of_device_id *match;
 311         struct fsl_msi *msi;
 312         struct resource res;
 313         int err, i, j, irq_index, count;
 314         int rc;
 315         const u32 *p;
 316         struct fsl_msi_feature *features;
 317         int len;
 318         u32 offset;
 319         static const u32 all_avail[] = { 0, NR_MSI_IRQS };
 320
 321         match = of_match_device(fsl_of_msi_ids, &dev->dev);
 322         if (!match)
 323                 return -EINVAL;
 324         features = match->data;
 325
 326         printk(KERN_DEBUG "Setting up Freescale MSI support\n");
 327
 328         msi = kzalloc(sizeof(struct fsl_msi), GFP_KERNEL);
 329         if (!msi) {
 330                 dev_err(&dev->dev, "No memory for MSI structure\n");
 331                 return -ENOMEM;
 332         }
 333         platform_set_drvdata(dev, msi);
 334
 335         msi->irqhost = irq_alloc_host(dev->dev.of_node, IRQ_HOST_MAP_LINEAR,
 336                                       NR_MSI_IRQS, &fsl_msi_host_ops, 0);
 337
 338         if (msi->irqhost == NULL) {
 339                 dev_err(&dev->dev, "No memory for MSI irqhost\n");
 340                 err = -ENOMEM;
 341                 goto error_out;
 342         }
 343
 344         /* Get the MSI reg base */
 345         err = of_address_to_resource(dev->dev.of_node, 0, &res);
 346         if (err) {
 347                 dev_err(&dev->dev, "%s resource error!\n",
 348                                 dev->dev.of_node->full_name);
 349                 goto error_out;
 350         }
 351
 352         msi->msi_regs = ioremap(res.start, res.end - res.start + 1);
 353         if (!msi->msi_regs) {
 354                 dev_err(&dev->dev, "ioremap problem failed\n");
 355                 goto error_out;
 356         }
 357
 358         msi->feature = features->fsl_pic_ip;
 359
 360         msi->irqhost->host_data = msi;
 361
 362         msi->msi_addr_hi = 0x0;
 363         msi->msi_addr_lo = features->msiir_offset + (res.start & 0xfffff);
 364
 365         rc = fsl_msi_init_allocator(msi);
 366         if (rc) {
 367                 dev_err(&dev->dev, "Error allocating MSI bitmap\n");
 368                 goto error_out;
 369         }
 370
 371         p = of_get_property(dev->dev.of_node, "msi-available-ranges", &len);
 372         if (p && len % (2 * sizeof(u32)) != 0) {
 373                 dev_err(&dev->dev, "%s: Malformed msi-available-ranges property\n",
 374                         __func__);
 375                 err = -EINVAL;
 376                 goto error_out;
 377         }
 378
 379         if (!p)
 380                 p = all_avail;
 381
 382         for (irq_index = 0, i = 0; i < len / (2 * sizeof(u32)); i++) {
 383                 if (p[i * 2] % IRQS_PER_MSI_REG ||
 384                     p[i * 2 + 1] % IRQS_PER_MSI_REG) {
 385                         printk(KERN_WARNING "%s: %s: msi available range of %u at %u is not IRQ-aligned\n",
 386                                __func__, dev->dev.of_node->full_name,
 387                                p[i * 2 + 1], p[i * 2]);
 388                         err = -EINVAL;
 389                         goto error_out;
 390                 }
 391
 392                 offset = p[i * 2] / IRQS_PER_MSI_REG;
 393                 count = p[i * 2 + 1] / IRQS_PER_MSI_REG;
 394
 395                 for (j = 0; j < count; j++, irq_index++) {
 396                         err = fsl_msi_setup_hwirq(msi, dev, offset, irq_index);
 397                         if (err)
 398                                 goto error_out;
 399                 }
 400         }
 401
 402         list_add_tail(&msi->list, &msi_head);
 403
 404         /* The multiple setting ppc_md.setup_msi_irqs will not harm things */
 405         if (!ppc_md.setup_msi_irqs) {
 406                 ppc_md.setup_msi_irqs = fsl_setup_msi_irqs;
 407                 ppc_md.teardown_msi_irqs = fsl_teardown_msi_irqs;
 408                 ppc_md.msi_check_device = fsl_msi_check_device;
 409         } else if (ppc_md.setup_msi_irqs != fsl_setup_msi_irqs) {
 410                 dev_err(&dev->dev, "Different MSI driver already installed!\n");
 411                 err = -ENODEV;
 412                 goto error_out;
 413         }
 414         return 0;
 415 error_out:
 416         fsl_of_msi_remove(dev);
 417         return err;
 418 }
 419
 420 static const struct fsl_msi_feature mpic_msi_feature = {
 421         .fsl_pic_ip = FSL_PIC_IP_MPIC,
 422         .msiir_offset = 0x140,
 423 };
 424
 425 static const struct fsl_msi_feature ipic_msi_feature = {
 426         .fsl_pic_ip = FSL_PIC_IP_IPIC,
 427         .msiir_offset = 0x38,
 428 };
 429
 430 static const struct of_device_id fsl_of_msi_ids[] = {
 431         {
 432                 .compatible = "fsl,mpic-msi",
 433                 .data = (void *)&mpic_msi_feature,
 434         },
 435         {
 436                 .compatible = "fsl,ipic-msi",
 437                 .data = (void *)&ipic_msi_feature,
 438         },
 439         {}
 440 };
 441
 442 static struct platform_driver fsl_of_msi_driver = {
 443         .driver = {
 444                 .name = "fsl-msi",
 445                 .owner = THIS_MODULE,
 446                 .of_match_table = fsl_of_msi_ids,
 447         },
 448         .probe = fsl_of_msi_probe,
 449         .remove = fsl_of_msi_remove,
 450 };
 451
 452 static __init int fsl_of_msi_init(void)
 453 {
 454         return platform_driver_register(&fsl_of_msi_driver);
 455 }
 456
 457 subsys_initcall(fsl_of_msi_init);