drivers/iommu/irq_remapping.c

   1 #include <linux/cpumask.h>
   2 #include <linux/kernel.h>
   3 #include <linux/string.h>
   4 #include <linux/cpumask.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 void irq_remapping_disable_io_apic(void)
  34 {
  35         /*
  36          * With interrupt-remapping, for now we will use virtual wire A
  37          * mode, as virtual wire B is little complex (need to configure
  38          * both IOAPIC RTE as well as interrupt-remapping table entry).
  39          * As this gets called during crash dump, keep this simple for
  40          * now.
  41          */
  42         if (cpu_has_apic || apic_from_smp_config())
  43                 disconnect_bsp_APIC(0);
  44 }
  45
  46 static int do_setup_msi_irqs(struct pci_dev *dev, int nvec)
  47 {
  48         int node, ret, sub_handle, index = 0;
  49         unsigned int irq;
  50         struct msi_desc *msidesc;
  51
  52         nvec = __roundup_pow_of_two(nvec);
  53
  54         WARN_ON(!list_is_singular(&dev->msi_list));
  55         msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
  56         WARN_ON(msidesc->irq);
  57         WARN_ON(msidesc->msi_attrib.multiple);
  58
  59         node = dev_to_node(&dev->dev);
  60         irq = __create_irqs(get_nr_irqs_gsi(), nvec, node);
  61         if (irq == 0)
  62                 return -ENOSPC;
  63
  64         msidesc->msi_attrib.multiple = ilog2(nvec);
  65         for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
  66                 if (!sub_handle) {
  67                         index = msi_alloc_remapped_irq(dev, irq, nvec);
  68                         if (index < 0) {
  69                                 ret = index;
  70                                 goto error;
  71                         }
  72                 } else {
  73                         ret = msi_setup_remapped_irq(dev, irq + sub_handle,
  74                                                      index, sub_handle);
  75                         if (ret < 0)
  76                                 goto error;
  77                 }
  78                 ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
  79                 if (ret < 0)
  80                         goto error;
  81         }
  82         return 0;
  83
  84 error:
  85         destroy_irqs(irq, nvec);
  86
  87         /*
  88          * Restore altered MSI descriptor fields and prevent just destroyed
  89          * IRQs from tearing down again in default_teardown_msi_irqs()
  90          */
  91         msidesc->irq = 0;
  92         msidesc->msi_attrib.multiple = 0;
  93
  94         return ret;
  95 }
  96
  97 static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
  98 {
  99         int node, ret, sub_handle, index = 0;
 100         struct msi_desc *msidesc;
 101         unsigned int irq;
 102
 103         node            = dev_to_node(&dev->dev);
 104         irq             = get_nr_irqs_gsi();
 105         sub_handle      = 0;
 106
 107         list_for_each_entry(msidesc, &dev->msi_list, list) {
 108
 109                 irq = create_irq_nr(irq, node);
 110                 if (irq == 0)
 111                         return -1;
 112
 113                 if (sub_handle == 0)
 114                         ret = index = msi_alloc_remapped_irq(dev, irq, nvec);
 115                 else
 116                         ret = msi_setup_remapped_irq(dev, irq, index, sub_handle);
 117
 118                 if (ret < 0)
 119                         goto error;
 120
 121                 ret = setup_msi_irq(dev, msidesc, irq, 0);
 122                 if (ret < 0)
 123                         goto error;
 124
 125                 sub_handle += 1;
 126                 irq        += 1;
 127         }
 128
 129         return 0;
 130
 131 error:
 132         destroy_irq(irq);
 133         return ret;
 134 }
 135
 136 static int irq_remapping_setup_msi_irqs(struct pci_dev *dev,
 137                                         int nvec, int type)
 138 {
 139         if (type == PCI_CAP_ID_MSI)
 140                 return do_setup_msi_irqs(dev, nvec);
 141         else
 142                 return do_setup_msix_irqs(dev, nvec);
 143 }
 144
 145 static void __init irq_remapping_modify_x86_ops(void)
 146 {
 147         x86_io_apic_ops.disable         = irq_remapping_disable_io_apic;
 148         x86_io_apic_ops.set_affinity    = set_remapped_irq_affinity;
 149         x86_msi.setup_msi_irqs          = irq_remapping_setup_msi_irqs;
 150         x86_msi.setup_hpet_msi          = setup_hpet_msi_remapped;
 151 }
 152
 153 static __init int setup_nointremap(char *str)
 154 {
 155         disable_irq_remap = 1;
 156         return 0;
 157 }
 158 early_param("nointremap", setup_nointremap);
 159
 160 static __init int setup_irqremap(char *str)
 161 {
 162         if (!str)
 163                 return -EINVAL;
 164
 165         while (*str) {
 166                 if (!strncmp(str, "on", 2))
 167                         disable_irq_remap = 0;
 168                 else if (!strncmp(str, "off", 3))
 169                         disable_irq_remap = 1;
 170                 else if (!strncmp(str, "nosid", 5))
 171                         disable_sourceid_checking = 1;
 172                 else if (!strncmp(str, "no_x2apic_optout", 16))
 173                         no_x2apic_optout = 1;
 174
 175                 str += strcspn(str, ",");
 176                 while (*str == ',')
 177                         str++;
 178         }
 179
 180         return 0;
 181 }
 182 early_param("intremap", setup_irqremap);
 183
 184 void __init setup_irq_remapping_ops(void)
 185 {
 186         remap_ops = &intel_irq_remap_ops;
 187
 188 #ifdef CONFIG_AMD_IOMMU
 189         if (amd_iommu_irq_ops.prepare() == 0)
 190                 remap_ops = &amd_iommu_irq_ops;
 191 #endif
 192 }
 193
 194 int irq_remapping_supported(void)
 195 {
 196         if (disable_irq_remap)
 197                 return 0;
 198
 199         if (!remap_ops || !remap_ops->supported)
 200                 return 0;
 201
 202         return remap_ops->supported();
 203 }
 204
 205 int __init irq_remapping_prepare(void)
 206 {
 207         if (!remap_ops || !remap_ops->prepare)
 208                 return -ENODEV;
 209
 210         return remap_ops->prepare();
 211 }
 212
 213 int __init irq_remapping_enable(void)
 214 {
 215         int ret;
 216
 217         if (!remap_ops || !remap_ops->enable)
 218                 return -ENODEV;
 219
 220         ret = remap_ops->enable();
 221
 222         if (irq_remapping_enabled)
 223                 irq_remapping_modify_x86_ops();
 224
 225         return ret;
 226 }
 227
 228 void irq_remapping_disable(void)
 229 {
 230         if (!irq_remapping_enabled ||
 231             !remap_ops ||
 232             !remap_ops->disable)
 233                 return;
 234
 235         remap_ops->disable();
 236 }
 237
 238 int irq_remapping_reenable(int mode)
 239 {
 240         if (!irq_remapping_enabled ||
 241             !remap_ops ||
 242             !remap_ops->reenable)
 243                 return 0;
 244
 245         return remap_ops->reenable(mode);
 246 }
 247
 248 int __init irq_remap_enable_fault_handling(void)
 249 {
 250         if (!irq_remapping_enabled)
 251                 return 0;
 252
 253         if (!remap_ops || !remap_ops->enable_faulting)
 254                 return -ENODEV;
 255
 256         return remap_ops->enable_faulting();
 257 }
 258
 259 int setup_ioapic_remapped_entry(int irq,
 260                                 struct IO_APIC_route_entry *entry,
 261                                 unsigned int destination, int vector,
 262                                 struct io_apic_irq_attr *attr)
 263 {
 264         if (!remap_ops || !remap_ops->setup_ioapic_entry)
 265                 return -ENODEV;
 266
 267         return remap_ops->setup_ioapic_entry(irq, entry, destination,
 268                                              vector, attr);
 269 }
 270
 271 int set_remapped_irq_affinity(struct irq_data *data, const struct cpumask *mask,
 272                               bool force)
 273 {
 274         if (!config_enabled(CONFIG_SMP) || !remap_ops ||
 275             !remap_ops->set_affinity)
 276                 return 0;
 277
 278         return remap_ops->set_affinity(data, mask, force);
 279 }
 280
 281 void free_remapped_irq(int irq)
 282 {
 283         if (!remap_ops || !remap_ops->free_irq)
 284                 return;
 285
 286         remap_ops->free_irq(irq);
 287 }
 288
 289 void compose_remapped_msi_msg(struct pci_dev *pdev,
 290                               unsigned int irq, unsigned int dest,
 291                               struct msi_msg *msg, u8 hpet_id)
 292 {
 293         if (!remap_ops || !remap_ops->compose_msi_msg)
 294                 return;
 295
 296         remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 297 }
 298
 299 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
 300 {
 301         if (!remap_ops || !remap_ops->msi_alloc_irq)
 302                 return -ENODEV;
 303
 304         return remap_ops->msi_alloc_irq(pdev, irq, nvec);
 305 }
 306
 307 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
 308                                   int index, int sub_handle)
 309 {
 310         if (!remap_ops || !remap_ops->msi_setup_irq)
 311                 return -ENODEV;
 312
 313         return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle);
 314 }
 315
 316 int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
 317 {
 318         if (!remap_ops || !remap_ops->setup_hpet_msi)
 319                 return -ENODEV;
 320
 321         return remap_ops->setup_hpet_msi(irq, id);
 322 }