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 irq_remap_broken;
  22 int disable_sourceid_checking;
  23 int no_x2apic_optout;
  24
  25 static struct irq_remap_ops *remap_ops;
  26
  27 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec);
  28 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
  29                                   int index, int sub_handle);
  30 static int set_remapped_irq_affinity(struct irq_data *data,
  31                                      const struct cpumask *mask,
  32                                      bool force);
  33
  34 static bool irq_remapped(struct irq_cfg *cfg)
  35 {
  36         return (cfg->remapped == 1);
  37 }
  38
  39 static void irq_remapping_disable_io_apic(void)
  40 {
  41         /*
  42          * With interrupt-remapping, for now we will use virtual wire A
  43          * mode, as virtual wire B is little complex (need to configure
  44          * both IOAPIC RTE as well as interrupt-remapping table entry).
  45          * As this gets called during crash dump, keep this simple for
  46          * now.
  47          */
  48         if (cpu_has_apic || apic_from_smp_config())
  49                 disconnect_bsp_APIC(0);
  50 }
  51
  52 static int do_setup_msi_irqs(struct pci_dev *dev, int nvec)
  53 {
  54         int node, ret, sub_handle, nvec_pow2, index = 0;
  55         unsigned int irq;
  56         struct msi_desc *msidesc;
  57
  58         WARN_ON(!list_is_singular(&dev->msi_list));
  59         msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
  60         WARN_ON(msidesc->irq);
  61         WARN_ON(msidesc->msi_attrib.multiple);
  62         WARN_ON(msidesc->nvec_used);
  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         nvec_pow2 = __roundup_pow_of_two(nvec);
  70         msidesc->nvec_used = nvec;
  71         msidesc->msi_attrib.multiple = ilog2(nvec_pow2);
  72         for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
  73                 if (!sub_handle) {
  74                         index = msi_alloc_remapped_irq(dev, irq, nvec_pow2);
  75                         if (index < 0) {
  76                                 ret = index;
  77                                 goto error;
  78                         }
  79                 } else {
  80                         ret = msi_setup_remapped_irq(dev, irq + sub_handle,
  81                                                      index, sub_handle);
  82                         if (ret < 0)
  83                                 goto error;
  84                 }
  85                 ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
  86                 if (ret < 0)
  87                         goto error;
  88         }
  89         return 0;
  90
  91 error:
  92         destroy_irqs(irq, nvec);
  93
  94         /*
  95          * Restore altered MSI descriptor fields and prevent just destroyed
  96          * IRQs from tearing down again in default_teardown_msi_irqs()
  97          */
  98         msidesc->irq = 0;
  99         msidesc->nvec_used = 0;
 100         msidesc->msi_attrib.multiple = 0;
 101
 102         return ret;
 103 }
 104
 105 static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
 106 {
 107         int node, ret, sub_handle, index = 0;
 108         struct msi_desc *msidesc;
 109         unsigned int irq;
 110
 111         node            = dev_to_node(&dev->dev);
 112         irq             = get_nr_irqs_gsi();
 113         sub_handle      = 0;
 114
 115         list_for_each_entry(msidesc, &dev->msi_list, list) {
 116
 117                 irq = create_irq_nr(irq, node);
 118                 if (irq == 0)
 119                         return -1;
 120
 121                 if (sub_handle == 0)
 122                         ret = index = msi_alloc_remapped_irq(dev, irq, nvec);
 123                 else
 124                         ret = msi_setup_remapped_irq(dev, irq, index, sub_handle);
 125
 126                 if (ret < 0)
 127                         goto error;
 128
 129                 ret = setup_msi_irq(dev, msidesc, irq, 0);
 130                 if (ret < 0)
 131                         goto error;
 132
 133                 sub_handle += 1;
 134                 irq        += 1;
 135         }
 136
 137         return 0;
 138
 139 error:
 140         destroy_irq(irq);
 141         return ret;
 142 }
 143
 144 static int irq_remapping_setup_msi_irqs(struct pci_dev *dev,
 145                                         int nvec, int type)
 146 {
 147         if (type == PCI_CAP_ID_MSI)
 148                 return do_setup_msi_irqs(dev, nvec);
 149         else
 150                 return do_setup_msix_irqs(dev, nvec);
 151 }
 152
 153 static void eoi_ioapic_pin_remapped(int apic, int pin, int vector)
 154 {
 155         /*
 156          * Intr-remapping uses pin number as the virtual vector
 157          * in the RTE. Actual vector is programmed in
 158          * intr-remapping table entry. Hence for the io-apic
 159          * EOI we use the pin number.
 160          */
 161         io_apic_eoi(apic, pin);
 162 }
 163
 164 static void __init irq_remapping_modify_x86_ops(void)
 165 {
 166         x86_io_apic_ops.disable         = irq_remapping_disable_io_apic;
 167         x86_io_apic_ops.set_affinity    = set_remapped_irq_affinity;
 168         x86_io_apic_ops.setup_entry     = setup_ioapic_remapped_entry;
 169         x86_io_apic_ops.eoi_ioapic_pin  = eoi_ioapic_pin_remapped;
 170         x86_msi.setup_msi_irqs          = irq_remapping_setup_msi_irqs;
 171         x86_msi.setup_hpet_msi          = setup_hpet_msi_remapped;
 172         x86_msi.compose_msi_msg         = compose_remapped_msi_msg;
 173 }
 174
 175 static __init int setup_nointremap(char *str)
 176 {
 177         disable_irq_remap = 1;
 178         return 0;
 179 }
 180 early_param("nointremap", setup_nointremap);
 181
 182 static __init int setup_irqremap(char *str)
 183 {
 184         if (!str)
 185                 return -EINVAL;
 186
 187         while (*str) {
 188                 if (!strncmp(str, "on", 2))
 189                         disable_irq_remap = 0;
 190                 else if (!strncmp(str, "off", 3))
 191                         disable_irq_remap = 1;
 192                 else if (!strncmp(str, "nosid", 5))
 193                         disable_sourceid_checking = 1;
 194                 else if (!strncmp(str, "no_x2apic_optout", 16))
 195                         no_x2apic_optout = 1;
 196
 197                 str += strcspn(str, ",");
 198                 while (*str == ',')
 199                         str++;
 200         }
 201
 202         return 0;
 203 }
 204 early_param("intremap", setup_irqremap);
 205
 206 void __init setup_irq_remapping_ops(void)
 207 {
 208         remap_ops = &intel_irq_remap_ops;
 209
 210 #ifdef CONFIG_AMD_IOMMU
 211         if (amd_iommu_irq_ops.prepare() == 0)
 212                 remap_ops = &amd_iommu_irq_ops;
 213 #endif
 214 }
 215
 216 void set_irq_remapping_broken(void)
 217 {
 218         irq_remap_broken = 1;
 219 }
 220
 221 int irq_remapping_supported(void)
 222 {
 223         if (disable_irq_remap)
 224                 return 0;
 225
 226         if (!remap_ops || !remap_ops->supported)
 227                 return 0;
 228
 229         return remap_ops->supported();
 230 }
 231
 232 int __init irq_remapping_prepare(void)
 233 {
 234         if (!remap_ops || !remap_ops->prepare)
 235                 return -ENODEV;
 236
 237         return remap_ops->prepare();
 238 }
 239
 240 int __init irq_remapping_enable(void)
 241 {
 242         int ret;
 243
 244         if (!remap_ops || !remap_ops->enable)
 245                 return -ENODEV;
 246
 247         ret = remap_ops->enable();
 248
 249         if (irq_remapping_enabled)
 250                 irq_remapping_modify_x86_ops();
 251
 252         return ret;
 253 }
 254
 255 void irq_remapping_disable(void)
 256 {
 257         if (!irq_remapping_enabled ||
 258             !remap_ops ||
 259             !remap_ops->disable)
 260                 return;
 261
 262         remap_ops->disable();
 263 }
 264
 265 int irq_remapping_reenable(int mode)
 266 {
 267         if (!irq_remapping_enabled ||
 268             !remap_ops ||
 269             !remap_ops->reenable)
 270                 return 0;
 271
 272         return remap_ops->reenable(mode);
 273 }
 274
 275 int __init irq_remap_enable_fault_handling(void)
 276 {
 277         if (!irq_remapping_enabled)
 278                 return 0;
 279
 280         if (!remap_ops || !remap_ops->enable_faulting)
 281                 return -ENODEV;
 282
 283         return remap_ops->enable_faulting();
 284 }
 285
 286 int setup_ioapic_remapped_entry(int irq,
 287                                 struct IO_APIC_route_entry *entry,
 288                                 unsigned int destination, int vector,
 289                                 struct io_apic_irq_attr *attr)
 290 {
 291         if (!remap_ops || !remap_ops->setup_ioapic_entry)
 292                 return -ENODEV;
 293
 294         return remap_ops->setup_ioapic_entry(irq, entry, destination,
 295                                              vector, attr);
 296 }
 297
 298 static int set_remapped_irq_affinity(struct irq_data *data,
 299                                      const struct cpumask *mask, bool force)
 300 {
 301         if (!config_enabled(CONFIG_SMP) || !remap_ops ||
 302             !remap_ops->set_affinity)
 303                 return 0;
 304
 305         return remap_ops->set_affinity(data, mask, force);
 306 }
 307
 308 void free_remapped_irq(int irq)
 309 {
 310         struct irq_cfg *cfg = irq_get_chip_data(irq);
 311
 312         if (!remap_ops || !remap_ops->free_irq)
 313                 return;
 314
 315         if (irq_remapped(cfg))
 316                 remap_ops->free_irq(irq);
 317 }
 318
 319 void compose_remapped_msi_msg(struct pci_dev *pdev,
 320                               unsigned int irq, unsigned int dest,
 321                               struct msi_msg *msg, u8 hpet_id)
 322 {
 323         struct irq_cfg *cfg = irq_get_chip_data(irq);
 324
 325         if (!irq_remapped(cfg))
 326                 native_compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 327         else if (remap_ops && remap_ops->compose_msi_msg)
 328                 remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 329 }
 330
 331 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
 332 {
 333         if (!remap_ops || !remap_ops->msi_alloc_irq)
 334                 return -ENODEV;
 335
 336         return remap_ops->msi_alloc_irq(pdev, irq, nvec);
 337 }
 338
 339 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
 340                                   int index, int sub_handle)
 341 {
 342         if (!remap_ops || !remap_ops->msi_setup_irq)
 343                 return -ENODEV;
 344
 345         return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle);
 346 }
 347
 348 int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
 349 {
 350         if (!remap_ops || !remap_ops->setup_hpet_msi)
 351                 return -ENODEV;
 352
 353         return remap_ops->setup_hpet_msi(irq, id);
 354 }
 355
 356 void panic_if_irq_remap(const char *msg)
 357 {
 358         if (irq_remapping_enabled)
 359                 panic(msg);
 360 }
 361
 362 static void ir_ack_apic_edge(struct irq_data *data)
 363 {
 364         ack_APIC_irq();
 365 }
 366
 367 static void ir_ack_apic_level(struct irq_data *data)
 368 {
 369         ack_APIC_irq();
 370         eoi_ioapic_irq(data->irq, data->chip_data);
 371 }
 372
 373 static void ir_print_prefix(struct irq_data *data, struct seq_file *p)
 374 {
 375         seq_printf(p, " IR-%s", data->chip->name);
 376 }
 377
 378 void irq_remap_modify_chip_defaults(struct irq_chip *chip)
 379 {
 380         chip->irq_print_chip = ir_print_prefix;
 381         chip->irq_ack = ir_ack_apic_edge;
 382         chip->irq_eoi = ir_ack_apic_level;
 383         chip->irq_set_affinity = x86_io_apic_ops.set_affinity;
 384 }
 385
 386 bool setup_remapped_irq(int irq, struct irq_cfg *cfg, struct irq_chip *chip)
 387 {
 388         if (!irq_remapped(cfg))
 389                 return false;
 390         irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
 391         irq_remap_modify_chip_defaults(chip);
 392         return true;
 393 }