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/cpumask.h>
   6 #include <linux/errno.h>
   7 #include <linux/msi.h>
   8 #include <linux/irq.h>
   9 #include <linux/pci.h>
  10
  11 #include <asm/hw_irq.h>
  12 #include <asm/irq_remapping.h>
  13 #include <asm/processor.h>
  14 #include <asm/x86_init.h>
  15 #include <asm/apic.h>
  16
  17 #include "irq_remapping.h"
  18
  19 int irq_remapping_enabled;
  20
  21 int disable_irq_remap;
  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, index = 0;
  55         unsigned int irq;
  56         struct msi_desc *msidesc;
  57
  58         nvec = __roundup_pow_of_two(nvec);
  59
  60         WARN_ON(!list_is_singular(&dev->msi_list));
  61         msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
  62         WARN_ON(msidesc->irq);
  63         WARN_ON(msidesc->msi_attrib.multiple);
  64
  65         node = dev_to_node(&dev->dev);
  66         irq = __create_irqs(get_nr_irqs_gsi(), nvec, node);
  67         if (irq == 0)
  68                 return -ENOSPC;
  69
  70         msidesc->msi_attrib.multiple = ilog2(nvec);
  71         for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
  72                 if (!sub_handle) {
  73                         index = msi_alloc_remapped_irq(dev, irq, nvec);
  74                         if (index < 0) {
  75                                 ret = index;
  76                                 goto error;
  77                         }
  78                 } else {
  79                         ret = msi_setup_remapped_irq(dev, irq + sub_handle,
  80                                                      index, sub_handle);
  81                         if (ret < 0)
  82                                 goto error;
  83                 }
  84                 ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
  85                 if (ret < 0)
  86                         goto error;
  87         }
  88         return 0;
  89
  90 error:
  91         destroy_irqs(irq, nvec);
  92
  93         /*
  94          * Restore altered MSI descriptor fields and prevent just destroyed
  95          * IRQs from tearing down again in default_teardown_msi_irqs()
  96          */
  97         msidesc->irq = 0;
  98         msidesc->msi_attrib.multiple = 0;
  99
 100         return ret;
 101 }
 102
 103 static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
 104 {
 105         int node, ret, sub_handle, index = 0;
 106         struct msi_desc *msidesc;
 107         unsigned int irq;
 108
 109         node            = dev_to_node(&dev->dev);
 110         irq             = get_nr_irqs_gsi();
 111         sub_handle      = 0;
 112
 113         list_for_each_entry(msidesc, &dev->msi_list, list) {
 114
 115                 irq = create_irq_nr(irq, node);
 116                 if (irq == 0)
 117                         return -1;
 118
 119                 if (sub_handle == 0)
 120                         ret = index = msi_alloc_remapped_irq(dev, irq, nvec);
 121                 else
 122                         ret = msi_setup_remapped_irq(dev, irq, index, sub_handle);
 123
 124                 if (ret < 0)
 125                         goto error;
 126
 127                 ret = setup_msi_irq(dev, msidesc, irq, 0);
 128                 if (ret < 0)
 129                         goto error;
 130
 131                 sub_handle += 1;
 132                 irq        += 1;
 133         }
 134
 135         return 0;
 136
 137 error:
 138         destroy_irq(irq);
 139         return ret;
 140 }
 141
 142 static int irq_remapping_setup_msi_irqs(struct pci_dev *dev,
 143                                         int nvec, int type)
 144 {
 145         if (type == PCI_CAP_ID_MSI)
 146                 return do_setup_msi_irqs(dev, nvec);
 147         else
 148                 return do_setup_msix_irqs(dev, nvec);
 149 }
 150
 151 void eoi_ioapic_pin_remapped(int apic, int pin, int vector)
 152 {
 153         /*
 154          * Intr-remapping uses pin number as the virtual vector
 155          * in the RTE. Actual vector is programmed in
 156          * intr-remapping table entry. Hence for the io-apic
 157          * EOI we use the pin number.
 158          */
 159         io_apic_eoi(apic, pin);
 160 }
 161
 162 static void __init irq_remapping_modify_x86_ops(void)
 163 {
 164         x86_io_apic_ops.disable         = irq_remapping_disable_io_apic;
 165         x86_io_apic_ops.set_affinity    = set_remapped_irq_affinity;
 166         x86_io_apic_ops.setup_entry     = setup_ioapic_remapped_entry;
 167         x86_io_apic_ops.eoi_ioapic_pin  = eoi_ioapic_pin_remapped;
 168         x86_msi.setup_msi_irqs          = irq_remapping_setup_msi_irqs;
 169         x86_msi.setup_hpet_msi          = setup_hpet_msi_remapped;
 170         x86_msi.compose_msi_msg         = compose_remapped_msi_msg;
 171 }
 172
 173 static __init int setup_nointremap(char *str)
 174 {
 175         disable_irq_remap = 1;
 176         return 0;
 177 }
 178 early_param("nointremap", setup_nointremap);
 179
 180 static __init int setup_irqremap(char *str)
 181 {
 182         if (!str)
 183                 return -EINVAL;
 184
 185         while (*str) {
 186                 if (!strncmp(str, "on", 2))
 187                         disable_irq_remap = 0;
 188                 else if (!strncmp(str, "off", 3))
 189                         disable_irq_remap = 1;
 190                 else if (!strncmp(str, "nosid", 5))
 191                         disable_sourceid_checking = 1;
 192                 else if (!strncmp(str, "no_x2apic_optout", 16))
 193                         no_x2apic_optout = 1;
 194
 195                 str += strcspn(str, ",");
 196                 while (*str == ',')
 197                         str++;
 198         }
 199
 200         return 0;
 201 }
 202 early_param("intremap", setup_irqremap);
 203
 204 void __init setup_irq_remapping_ops(void)
 205 {
 206         remap_ops = &intel_irq_remap_ops;
 207
 208 #ifdef CONFIG_AMD_IOMMU
 209         if (amd_iommu_irq_ops.prepare() == 0)
 210                 remap_ops = &amd_iommu_irq_ops;
 211 #endif
 212 }
 213
 214 int irq_remapping_supported(void)
 215 {
 216         if (disable_irq_remap)
 217                 return 0;
 218
 219         if (!remap_ops || !remap_ops->supported)
 220                 return 0;
 221
 222         return remap_ops->supported();
 223 }
 224
 225 int __init irq_remapping_prepare(void)
 226 {
 227         if (!remap_ops || !remap_ops->prepare)
 228                 return -ENODEV;
 229
 230         return remap_ops->prepare();
 231 }
 232
 233 int __init irq_remapping_enable(void)
 234 {
 235         int ret;
 236
 237         if (!remap_ops || !remap_ops->enable)
 238                 return -ENODEV;
 239
 240         ret = remap_ops->enable();
 241
 242         if (irq_remapping_enabled)
 243                 irq_remapping_modify_x86_ops();
 244
 245         return ret;
 246 }
 247
 248 void irq_remapping_disable(void)
 249 {
 250         if (!irq_remapping_enabled ||
 251             !remap_ops ||
 252             !remap_ops->disable)
 253                 return;
 254
 255         remap_ops->disable();
 256 }
 257
 258 int irq_remapping_reenable(int mode)
 259 {
 260         if (!irq_remapping_enabled ||
 261             !remap_ops ||
 262             !remap_ops->reenable)
 263                 return 0;
 264
 265         return remap_ops->reenable(mode);
 266 }
 267
 268 int __init irq_remap_enable_fault_handling(void)
 269 {
 270         if (!irq_remapping_enabled)
 271                 return 0;
 272
 273         if (!remap_ops || !remap_ops->enable_faulting)
 274                 return -ENODEV;
 275
 276         return remap_ops->enable_faulting();
 277 }
 278
 279 int setup_ioapic_remapped_entry(int irq,
 280                                 struct IO_APIC_route_entry *entry,
 281                                 unsigned int destination, int vector,
 282                                 struct io_apic_irq_attr *attr)
 283 {
 284         if (!remap_ops || !remap_ops->setup_ioapic_entry)
 285                 return -ENODEV;
 286
 287         return remap_ops->setup_ioapic_entry(irq, entry, destination,
 288                                              vector, attr);
 289 }
 290
 291 int set_remapped_irq_affinity(struct irq_data *data, const struct cpumask *mask,
 292                               bool force)
 293 {
 294         if (!config_enabled(CONFIG_SMP) || !remap_ops ||
 295             !remap_ops->set_affinity)
 296                 return 0;
 297
 298         return remap_ops->set_affinity(data, mask, force);
 299 }
 300
 301 void free_remapped_irq(int irq)
 302 {
 303         struct irq_cfg *cfg = irq_get_chip_data(irq);
 304
 305         if (!remap_ops || !remap_ops->free_irq)
 306                 return;
 307
 308         if (irq_remapped(cfg))
 309                 remap_ops->free_irq(irq);
 310 }
 311
 312 void compose_remapped_msi_msg(struct pci_dev *pdev,
 313                               unsigned int irq, unsigned int dest,
 314                               struct msi_msg *msg, u8 hpet_id)
 315 {
 316         struct irq_cfg *cfg = irq_get_chip_data(irq);
 317
 318         if (!irq_remapped(cfg))
 319                 native_compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 320         else if (remap_ops && remap_ops->compose_msi_msg)
 321                 remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 322 }
 323
 324 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
 325 {
 326         if (!remap_ops || !remap_ops->msi_alloc_irq)
 327                 return -ENODEV;
 328
 329         return remap_ops->msi_alloc_irq(pdev, irq, nvec);
 330 }
 331
 332 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
 333                                   int index, int sub_handle)
 334 {
 335         if (!remap_ops || !remap_ops->msi_setup_irq)
 336                 return -ENODEV;
 337
 338         return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle);
 339 }
 340
 341 int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
 342 {
 343         if (!remap_ops || !remap_ops->setup_hpet_msi)
 344                 return -ENODEV;
 345
 346         return remap_ops->setup_hpet_msi(irq, id);
 347 }
 348
 349 void panic_if_irq_remap(const char *msg)
 350 {
 351         if (irq_remapping_enabled)
 352                 panic(msg);
 353 }
 354
 355 static void ir_ack_apic_edge(struct irq_data *data)
 356 {
 357         ack_APIC_irq();
 358 }
 359
 360 static void ir_ack_apic_level(struct irq_data *data)
 361 {
 362         ack_APIC_irq();
 363         eoi_ioapic_irq(data->irq, data->chip_data);
 364 }
 365
 366 static void ir_print_prefix(struct irq_data *data, struct seq_file *p)
 367 {
 368         seq_printf(p, " IR-%s", data->chip->name);
 369 }
 370
 371 void irq_remap_modify_chip_defaults(struct irq_chip *chip)
 372 {
 373         chip->irq_print_chip = ir_print_prefix;
 374         chip->irq_ack = ir_ack_apic_edge;
 375         chip->irq_eoi = ir_ack_apic_level;
 376         chip->irq_set_affinity = x86_io_apic_ops.set_affinity;
 377 }
 378
 379 bool setup_remapped_irq(int irq, struct irq_cfg *cfg, struct irq_chip *chip)
 380 {
 381         if (!irq_remapped(cfg))
 382                 return false;
 383         irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
 384         irq_remap_modify_chip_defaults(chip);
 385         return true;
 386 }