drivers/iommu/irq_remapping.c

   1 #include <linux/seq_file.h>
   2 #include <linux/cpumask.h>
   3 #include <linux/kernel.h>
   4 #include <linux/string.h>
   5 #include <linux/errno.h>
   6 #include <linux/msi.h>
   7 #include <linux/irq.h>
   8 #include <linux/pci.h>
   9
  10 #include <asm/hw_irq.h>
  11 #include <asm/irq_remapping.h>
  12 #include <asm/processor.h>
  13 #include <asm/x86_init.h>
  14 #include <asm/apic.h>
  15
  16 #include "irq_remapping.h"
  17
  18 int irq_remapping_enabled;
  19
  20 int disable_irq_remap;
  21 int disable_sourceid_checking;
  22 int no_x2apic_optout;
  23
  24 static struct irq_remap_ops *remap_ops;
  25
  26 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec);
  27 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
  28                                   int index, int sub_handle);
  29 static int set_remapped_irq_affinity(struct irq_data *data,
  30                                      const struct cpumask *mask,
  31                                      bool force);
  32
  33 static bool irq_remapped(struct irq_cfg *cfg)
  34 {
  35         return (cfg->remapped == 1);
  36 }
  37
  38 static void irq_remapping_disable_io_apic(void)
  39 {
  40         /*
  41          * With interrupt-remapping, for now we will use virtual wire A
  42          * mode, as virtual wire B is little complex (need to configure
  43          * both IOAPIC RTE as well as interrupt-remapping table entry).
  44          * As this gets called during crash dump, keep this simple for
  45          * now.
  46          */
  47         if (cpu_has_apic || apic_from_smp_config())
  48                 disconnect_bsp_APIC(0);
  49 }
  50
  51 static int do_setup_msi_irqs(struct pci_dev *dev, int nvec)
  52 {
  53         int node, ret, sub_handle, index = 0;
  54         unsigned int irq;
  55         struct msi_desc *msidesc;
  56
  57         nvec = __roundup_pow_of_two(nvec);
  58
  59         WARN_ON(!list_is_singular(&dev->msi_list));
  60         msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
  61         WARN_ON(msidesc->irq);
  62         WARN_ON(msidesc->msi_attrib.multiple);
  63
  64         node = dev_to_node(&dev->dev);
  65         irq = __create_irqs(get_nr_irqs_gsi(), nvec, node);
  66         if (irq == 0)
  67                 return -ENOSPC;
  68
  69         msidesc->msi_attrib.multiple = ilog2(nvec);
  70         for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
  71                 if (!sub_handle) {
  72                         index = msi_alloc_remapped_irq(dev, irq, nvec);
  73                         if (index < 0) {
  74                                 ret = index;
  75                                 goto error;
  76                         }
  77                 } else {
  78                         ret = msi_setup_remapped_irq(dev, irq + sub_handle,
  79                                                      index, sub_handle);
  80                         if (ret < 0)
  81                                 goto error;
  82                 }
  83                 ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
  84                 if (ret < 0)
  85                         goto error;
  86         }
  87         return 0;
  88
  89 error:
  90         destroy_irqs(irq, nvec);
  91
  92         /*
  93          * Restore altered MSI descriptor fields and prevent just destroyed
  94          * IRQs from tearing down again in default_teardown_msi_irqs()
  95          */
  96         msidesc->irq = 0;
  97         msidesc->msi_attrib.multiple = 0;
  98
  99         return ret;
 100 }
 101
 102 static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
 103 {
 104         int node, ret, sub_handle, index = 0;
 105         struct msi_desc *msidesc;
 106         unsigned int irq;
 107
 108         node            = dev_to_node(&dev->dev);
 109         irq             = get_nr_irqs_gsi();
 110         sub_handle      = 0;
 111
 112         list_for_each_entry(msidesc, &dev->msi_list, list) {
 113
 114                 irq = create_irq_nr(irq, node);
 115                 if (irq == 0)
 116                         return -1;
 117
 118                 if (sub_handle == 0)
 119                         ret = index = msi_alloc_remapped_irq(dev, irq, nvec);
 120                 else
 121                         ret = msi_setup_remapped_irq(dev, irq, index, sub_handle);
 122
 123                 if (ret < 0)
 124                         goto error;
 125
 126                 ret = setup_msi_irq(dev, msidesc, irq, 0);
 127                 if (ret < 0)
 128                         goto error;
 129
 130                 sub_handle += 1;
 131                 irq        += 1;
 132         }
 133
 134         return 0;
 135
 136 error:
 137         destroy_irq(irq);
 138         return ret;
 139 }
 140
 141 static int irq_remapping_setup_msi_irqs(struct pci_dev *dev,
 142                                         int nvec, int type)
 143 {
 144         if (type == PCI_CAP_ID_MSI)
 145                 return do_setup_msi_irqs(dev, nvec);
 146         else
 147                 return do_setup_msix_irqs(dev, nvec);
 148 }
 149
 150 void eoi_ioapic_pin_remapped(int apic, int pin, int vector)
 151 {
 152         /*
 153          * Intr-remapping uses pin number as the virtual vector
 154          * in the RTE. Actual vector is programmed in
 155          * intr-remapping table entry. Hence for the io-apic
 156          * EOI we use the pin number.
 157          */
 158         io_apic_eoi(apic, pin);
 159 }
 160
 161 static void __init irq_remapping_modify_x86_ops(void)
 162 {
 163         x86_io_apic_ops.disable         = irq_remapping_disable_io_apic;
 164         x86_io_apic_ops.set_affinity    = set_remapped_irq_affinity;
 165         x86_io_apic_ops.setup_entry     = setup_ioapic_remapped_entry;
 166         x86_io_apic_ops.eoi_ioapic_pin  = eoi_ioapic_pin_remapped;
 167         x86_msi.setup_msi_irqs          = irq_remapping_setup_msi_irqs;
 168         x86_msi.setup_hpet_msi          = setup_hpet_msi_remapped;
 169         x86_msi.compose_msi_msg         = compose_remapped_msi_msg;
 170 }
 171
 172 static __init int setup_nointremap(char *str)
 173 {
 174         disable_irq_remap = 1;
 175         return 0;
 176 }
 177 early_param("nointremap", setup_nointremap);
 178
 179 static __init int setup_irqremap(char *str)
 180 {
 181         if (!str)
 182                 return -EINVAL;
 183
 184         while (*str) {
 185                 if (!strncmp(str, "on", 2))
 186                         disable_irq_remap = 0;
 187                 else if (!strncmp(str, "off", 3))
 188                         disable_irq_remap = 1;
 189                 else if (!strncmp(str, "nosid", 5))
 190                         disable_sourceid_checking = 1;
 191                 else if (!strncmp(str, "no_x2apic_optout", 16))
 192                         no_x2apic_optout = 1;
 193
 194                 str += strcspn(str, ",");
 195                 while (*str == ',')
 196                         str++;
 197         }
 198
 199         return 0;
 200 }
 201 early_param("intremap", setup_irqremap);
 202
 203 void __init setup_irq_remapping_ops(void)
 204 {
 205         remap_ops = &intel_irq_remap_ops;
 206
 207 #ifdef CONFIG_AMD_IOMMU
 208         if (amd_iommu_irq_ops.prepare() == 0)
 209                 remap_ops = &amd_iommu_irq_ops;
 210 #endif
 211 }
 212
 213 int irq_remapping_supported(void)
 214 {
 215         if (disable_irq_remap)
 216                 return 0;
 217
 218         if (!remap_ops || !remap_ops->supported)
 219                 return 0;
 220
 221         return remap_ops->supported();
 222 }
 223
 224 int __init irq_remapping_prepare(void)
 225 {
 226         if (!remap_ops || !remap_ops->prepare)
 227                 return -ENODEV;
 228
 229         return remap_ops->prepare();
 230 }
 231
 232 int __init irq_remapping_enable(void)
 233 {
 234         int ret;
 235
 236         if (!remap_ops || !remap_ops->enable)
 237                 return -ENODEV;
 238
 239         ret = remap_ops->enable();
 240
 241         if (irq_remapping_enabled)
 242                 irq_remapping_modify_x86_ops();
 243
 244         return ret;
 245 }
 246
 247 void irq_remapping_disable(void)
 248 {
 249         if (!irq_remapping_enabled ||
 250             !remap_ops ||
 251             !remap_ops->disable)
 252                 return;
 253
 254         remap_ops->disable();
 255 }
 256
 257 int irq_remapping_reenable(int mode)
 258 {
 259         if (!irq_remapping_enabled ||
 260             !remap_ops ||
 261             !remap_ops->reenable)
 262                 return 0;
 263
 264         return remap_ops->reenable(mode);
 265 }
 266
 267 int __init irq_remap_enable_fault_handling(void)
 268 {
 269         if (!irq_remapping_enabled)
 270                 return 0;
 271
 272         if (!remap_ops || !remap_ops->enable_faulting)
 273                 return -ENODEV;
 274
 275         return remap_ops->enable_faulting();
 276 }
 277
 278 int setup_ioapic_remapped_entry(int irq,
 279                                 struct IO_APIC_route_entry *entry,
 280                                 unsigned int destination, int vector,
 281                                 struct io_apic_irq_attr *attr)
 282 {
 283         if (!remap_ops || !remap_ops->setup_ioapic_entry)
 284                 return -ENODEV;
 285
 286         return remap_ops->setup_ioapic_entry(irq, entry, destination,
 287                                              vector, attr);
 288 }
 289
 290 int set_remapped_irq_affinity(struct irq_data *data, const struct cpumask *mask,
 291                               bool force)
 292 {
 293         if (!config_enabled(CONFIG_SMP) || !remap_ops ||
 294             !remap_ops->set_affinity)
 295                 return 0;
 296
 297         return remap_ops->set_affinity(data, mask, force);
 298 }
 299
 300 void free_remapped_irq(int irq)
 301 {
 302         struct irq_cfg *cfg = irq_get_chip_data(irq);
 303
 304         if (!remap_ops || !remap_ops->free_irq)
 305                 return;
 306
 307         if (irq_remapped(cfg))
 308                 remap_ops->free_irq(irq);
 309 }
 310
 311 void compose_remapped_msi_msg(struct pci_dev *pdev,
 312                               unsigned int irq, unsigned int dest,
 313                               struct msi_msg *msg, u8 hpet_id)
 314 {
 315         struct irq_cfg *cfg = irq_get_chip_data(irq);
 316
 317         if (!irq_remapped(cfg))
 318                 native_compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 319         else if (remap_ops && remap_ops->compose_msi_msg)
 320                 remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 321 }
 322
 323 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
 324 {
 325         if (!remap_ops || !remap_ops->msi_alloc_irq)
 326                 return -ENODEV;
 327
 328         return remap_ops->msi_alloc_irq(pdev, irq, nvec);
 329 }
 330
 331 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
 332                                   int index, int sub_handle)
 333 {
 334         if (!remap_ops || !remap_ops->msi_setup_irq)
 335                 return -ENODEV;
 336
 337         return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle);
 338 }
 339
 340 int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
 341 {
 342         if (!remap_ops || !remap_ops->setup_hpet_msi)
 343                 return -ENODEV;
 344
 345         return remap_ops->setup_hpet_msi(irq, id);
 346 }
 347
 348 void panic_if_irq_remap(const char *msg)
 349 {
 350         if (irq_remapping_enabled)
 351                 panic(msg);
 352 }
 353
 354 static void ir_ack_apic_edge(struct irq_data *data)
 355 {
 356         ack_APIC_irq();
 357 }
 358
 359 static void ir_ack_apic_level(struct irq_data *data)
 360 {
 361         ack_APIC_irq();
 362         eoi_ioapic_irq(data->irq, data->chip_data);
 363 }
 364
 365 static void ir_print_prefix(struct irq_data *data, struct seq_file *p)
 366 {
 367         seq_printf(p, " IR-%s", data->chip->name);
 368 }
 369
 370 void irq_remap_modify_chip_defaults(struct irq_chip *chip)
 371 {
 372         chip->irq_print_chip = ir_print_prefix;
 373         chip->irq_ack = ir_ack_apic_edge;
 374         chip->irq_eoi = ir_ack_apic_level;
 375         chip->irq_set_affinity = x86_io_apic_ops.set_affinity;
 376 }
 377
 378 bool setup_remapped_irq(int irq, struct irq_cfg *cfg, struct irq_chip *chip)
 379 {
 380         if (!irq_remapped(cfg))
 381                 return false;
 382         irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
 383         irq_remap_modify_chip_defaults(chip);
 384         return true;
 385 }