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 void eoi_ioapic_pin_remapped(int apic, int pin, int vector)
 147 {
 148         /*
 149          * Intr-remapping uses pin number as the virtual vector
 150          * in the RTE. Actual vector is programmed in
 151          * intr-remapping table entry. Hence for the io-apic
 152          * EOI we use the pin number.
 153          */
 154         io_apic_eoi(apic, pin);
 155 }
 156
 157 static void __init irq_remapping_modify_x86_ops(void)
 158 {
 159         x86_io_apic_ops.disable         = irq_remapping_disable_io_apic;
 160         x86_io_apic_ops.set_affinity    = set_remapped_irq_affinity;
 161         x86_io_apic_ops.setup_entry     = setup_ioapic_remapped_entry;
 162         x86_io_apic_ops.eoi_ioapic_pin  = eoi_ioapic_pin_remapped;
 163         x86_msi.setup_msi_irqs          = irq_remapping_setup_msi_irqs;
 164         x86_msi.setup_hpet_msi          = setup_hpet_msi_remapped;
 165         x86_msi.compose_msi_msg         = compose_remapped_msi_msg;
 166 }
 167
 168 static __init int setup_nointremap(char *str)
 169 {
 170         disable_irq_remap = 1;
 171         return 0;
 172 }
 173 early_param("nointremap", setup_nointremap);
 174
 175 static __init int setup_irqremap(char *str)
 176 {
 177         if (!str)
 178                 return -EINVAL;
 179
 180         while (*str) {
 181                 if (!strncmp(str, "on", 2))
 182                         disable_irq_remap = 0;
 183                 else if (!strncmp(str, "off", 3))
 184                         disable_irq_remap = 1;
 185                 else if (!strncmp(str, "nosid", 5))
 186                         disable_sourceid_checking = 1;
 187                 else if (!strncmp(str, "no_x2apic_optout", 16))
 188                         no_x2apic_optout = 1;
 189
 190                 str += strcspn(str, ",");
 191                 while (*str == ',')
 192                         str++;
 193         }
 194
 195         return 0;
 196 }
 197 early_param("intremap", setup_irqremap);
 198
 199 void __init setup_irq_remapping_ops(void)
 200 {
 201         remap_ops = &intel_irq_remap_ops;
 202
 203 #ifdef CONFIG_AMD_IOMMU
 204         if (amd_iommu_irq_ops.prepare() == 0)
 205                 remap_ops = &amd_iommu_irq_ops;
 206 #endif
 207 }
 208
 209 int irq_remapping_supported(void)
 210 {
 211         if (disable_irq_remap)
 212                 return 0;
 213
 214         if (!remap_ops || !remap_ops->supported)
 215                 return 0;
 216
 217         return remap_ops->supported();
 218 }
 219
 220 int __init irq_remapping_prepare(void)
 221 {
 222         if (!remap_ops || !remap_ops->prepare)
 223                 return -ENODEV;
 224
 225         return remap_ops->prepare();
 226 }
 227
 228 int __init irq_remapping_enable(void)
 229 {
 230         int ret;
 231
 232         if (!remap_ops || !remap_ops->enable)
 233                 return -ENODEV;
 234
 235         ret = remap_ops->enable();
 236
 237         if (irq_remapping_enabled)
 238                 irq_remapping_modify_x86_ops();
 239
 240         return ret;
 241 }
 242
 243 void irq_remapping_disable(void)
 244 {
 245         if (!irq_remapping_enabled ||
 246             !remap_ops ||
 247             !remap_ops->disable)
 248                 return;
 249
 250         remap_ops->disable();
 251 }
 252
 253 int irq_remapping_reenable(int mode)
 254 {
 255         if (!irq_remapping_enabled ||
 256             !remap_ops ||
 257             !remap_ops->reenable)
 258                 return 0;
 259
 260         return remap_ops->reenable(mode);
 261 }
 262
 263 int __init irq_remap_enable_fault_handling(void)
 264 {
 265         if (!irq_remapping_enabled)
 266                 return 0;
 267
 268         if (!remap_ops || !remap_ops->enable_faulting)
 269                 return -ENODEV;
 270
 271         return remap_ops->enable_faulting();
 272 }
 273
 274 int setup_ioapic_remapped_entry(int irq,
 275                                 struct IO_APIC_route_entry *entry,
 276                                 unsigned int destination, int vector,
 277                                 struct io_apic_irq_attr *attr)
 278 {
 279         if (!remap_ops || !remap_ops->setup_ioapic_entry)
 280                 return -ENODEV;
 281
 282         return remap_ops->setup_ioapic_entry(irq, entry, destination,
 283                                              vector, attr);
 284 }
 285
 286 int set_remapped_irq_affinity(struct irq_data *data, const struct cpumask *mask,
 287                               bool force)
 288 {
 289         if (!config_enabled(CONFIG_SMP) || !remap_ops ||
 290             !remap_ops->set_affinity)
 291                 return 0;
 292
 293         return remap_ops->set_affinity(data, mask, force);
 294 }
 295
 296 void free_remapped_irq(int irq)
 297 {
 298         struct irq_cfg *cfg = irq_get_chip_data(irq);
 299
 300         if (!remap_ops || !remap_ops->free_irq)
 301                 return;
 302
 303         if (irq_remapped(cfg))
 304                 remap_ops->free_irq(irq);
 305 }
 306
 307 void compose_remapped_msi_msg(struct pci_dev *pdev,
 308                               unsigned int irq, unsigned int dest,
 309                               struct msi_msg *msg, u8 hpet_id)
 310 {
 311         struct irq_cfg *cfg = irq_get_chip_data(irq);
 312
 313         if (!irq_remapped(cfg))
 314                 native_compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 315         else if (remap_ops && remap_ops->compose_msi_msg)
 316                 remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 317 }
 318
 319 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
 320 {
 321         if (!remap_ops || !remap_ops->msi_alloc_irq)
 322                 return -ENODEV;
 323
 324         return remap_ops->msi_alloc_irq(pdev, irq, nvec);
 325 }
 326
 327 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
 328                                   int index, int sub_handle)
 329 {
 330         if (!remap_ops || !remap_ops->msi_setup_irq)
 331                 return -ENODEV;
 332
 333         return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle);
 334 }
 335
 336 int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
 337 {
 338         if (!remap_ops || !remap_ops->setup_hpet_msi)
 339                 return -ENODEV;
 340
 341         return remap_ops->setup_hpet_msi(irq, id);
 342 }
 343
 344 void panic_if_irq_remap(const char *msg)
 345 {
 346         if (irq_remapping_enabled)
 347                 panic(msg);
 348 }
 349
 350 static void ir_ack_apic_edge(struct irq_data *data)
 351 {
 352         ack_APIC_irq();
 353 }
 354
 355 static void ir_ack_apic_level(struct irq_data *data)
 356 {
 357         ack_APIC_irq();
 358         eoi_ioapic_irq(data->irq, data->chip_data);
 359 }
 360
 361 static void ir_print_prefix(struct irq_data *data, struct seq_file *p)
 362 {
 363         seq_printf(p, " IR-%s", data->chip->name);
 364 }
 365
 366 void irq_remap_modify_chip_defaults(struct irq_chip *chip)
 367 {
 368         chip->irq_print_chip = ir_print_prefix;
 369         chip->irq_ack = ir_ack_apic_edge;
 370         chip->irq_eoi = ir_ack_apic_level;
 371         chip->irq_set_affinity = x86_io_apic_ops.set_affinity;
 372 }
 373
 374 bool setup_remapped_irq(int irq, struct irq_cfg *cfg, struct irq_chip *chip)
 375 {
 376         if (!irq_remapped(cfg))
 377                 return false;
 378         irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
 379         irq_remap_modify_chip_defaults(chip);
 380         return true;
 381 }