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