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
  30 static void irq_remapping_disable_io_apic(void)
  31 {
  32         /*
  33          * With interrupt-remapping, for now we will use virtual wire A
  34          * mode, as virtual wire B is little complex (need to configure
  35          * both IOAPIC RTE as well as interrupt-remapping table entry).
  36          * As this gets called during crash dump, keep this simple for
  37          * now.
  38          */
  39         if (cpu_has_apic || apic_from_smp_config())
  40                 disconnect_bsp_APIC(0);
  41 }
  42
  43 static int do_setup_msi_irqs(struct pci_dev *dev, int nvec)
  44 {
  45         int node, ret, sub_handle, index = 0;
  46         unsigned int irq;
  47         struct msi_desc *msidesc;
  48
  49         nvec = __roundup_pow_of_two(nvec);
  50
  51         WARN_ON(!list_is_singular(&dev->msi_list));
  52         msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
  53         WARN_ON(msidesc->irq);
  54         WARN_ON(msidesc->msi_attrib.multiple);
  55
  56         node = dev_to_node(&dev->dev);
  57         irq = __create_irqs(get_nr_irqs_gsi(), nvec, node);
  58         if (irq == 0)
  59                 return -ENOSPC;
  60
  61         msidesc->msi_attrib.multiple = ilog2(nvec);
  62         for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
  63                 if (!sub_handle) {
  64                         index = msi_alloc_remapped_irq(dev, irq, nvec);
  65                         if (index < 0) {
  66                                 ret = index;
  67                                 goto error;
  68                         }
  69                 } else {
  70                         ret = msi_setup_remapped_irq(dev, irq + sub_handle,
  71                                                      index, sub_handle);
  72                         if (ret < 0)
  73                                 goto error;
  74                 }
  75                 ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
  76                 if (ret < 0)
  77                         goto error;
  78         }
  79         return 0;
  80
  81 error:
  82         destroy_irqs(irq, nvec);
  83
  84         /*
  85          * Restore altered MSI descriptor fields and prevent just destroyed
  86          * IRQs from tearing down again in default_teardown_msi_irqs()
  87          */
  88         msidesc->irq = 0;
  89         msidesc->msi_attrib.multiple = 0;
  90
  91         return ret;
  92 }
  93
  94 static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
  95 {
  96         int node, ret, sub_handle, index = 0;
  97         struct msi_desc *msidesc;
  98         unsigned int irq;
  99
 100         node            = dev_to_node(&dev->dev);
 101         irq             = get_nr_irqs_gsi();
 102         sub_handle      = 0;
 103
 104         list_for_each_entry(msidesc, &dev->msi_list, list) {
 105
 106                 irq = create_irq_nr(irq, node);
 107                 if (irq == 0)
 108                         return -1;
 109
 110                 if (sub_handle == 0)
 111                         ret = index = msi_alloc_remapped_irq(dev, irq, nvec);
 112                 else
 113                         ret = msi_setup_remapped_irq(dev, irq, index, sub_handle);
 114
 115                 if (ret < 0)
 116                         goto error;
 117
 118                 ret = setup_msi_irq(dev, msidesc, irq, 0);
 119                 if (ret < 0)
 120                         goto error;
 121
 122                 sub_handle += 1;
 123                 irq        += 1;
 124         }
 125
 126         return 0;
 127
 128 error:
 129         destroy_irq(irq);
 130         return ret;
 131 }
 132
 133 static int irq_remapping_setup_msi_irqs(struct pci_dev *dev,
 134                                         int nvec, int type)
 135 {
 136         if (type == PCI_CAP_ID_MSI)
 137                 return do_setup_msi_irqs(dev, nvec);
 138         else
 139                 return do_setup_msix_irqs(dev, nvec);
 140 }
 141
 142 static void __init irq_remapping_modify_x86_ops(void)
 143 {
 144         x86_io_apic_ops.disable         = irq_remapping_disable_io_apic;
 145         x86_msi.setup_msi_irqs          = irq_remapping_setup_msi_irqs;
 146         x86_msi.setup_hpet_msi          = setup_hpet_msi_remapped;
 147 }
 148
 149 static __init int setup_nointremap(char *str)
 150 {
 151         disable_irq_remap = 1;
 152         return 0;
 153 }
 154 early_param("nointremap", setup_nointremap);
 155
 156 static __init int setup_irqremap(char *str)
 157 {
 158         if (!str)
 159                 return -EINVAL;
 160
 161         while (*str) {
 162                 if (!strncmp(str, "on", 2))
 163                         disable_irq_remap = 0;
 164                 else if (!strncmp(str, "off", 3))
 165                         disable_irq_remap = 1;
 166                 else if (!strncmp(str, "nosid", 5))
 167                         disable_sourceid_checking = 1;
 168                 else if (!strncmp(str, "no_x2apic_optout", 16))
 169                         no_x2apic_optout = 1;
 170
 171                 str += strcspn(str, ",");
 172                 while (*str == ',')
 173                         str++;
 174         }
 175
 176         return 0;
 177 }
 178 early_param("intremap", setup_irqremap);
 179
 180 void __init setup_irq_remapping_ops(void)
 181 {
 182         remap_ops = &intel_irq_remap_ops;
 183
 184 #ifdef CONFIG_AMD_IOMMU
 185         if (amd_iommu_irq_ops.prepare() == 0)
 186                 remap_ops = &amd_iommu_irq_ops;
 187 #endif
 188 }
 189
 190 int irq_remapping_supported(void)
 191 {
 192         if (disable_irq_remap)
 193                 return 0;
 194
 195         if (!remap_ops || !remap_ops->supported)
 196                 return 0;
 197
 198         return remap_ops->supported();
 199 }
 200
 201 int __init irq_remapping_prepare(void)
 202 {
 203         if (!remap_ops || !remap_ops->prepare)
 204                 return -ENODEV;
 205
 206         return remap_ops->prepare();
 207 }
 208
 209 int __init irq_remapping_enable(void)
 210 {
 211         int ret;
 212
 213         if (!remap_ops || !remap_ops->enable)
 214                 return -ENODEV;
 215
 216         ret = remap_ops->enable();
 217
 218         if (irq_remapping_enabled)
 219                 irq_remapping_modify_x86_ops();
 220
 221         return ret;
 222 }
 223
 224 void irq_remapping_disable(void)
 225 {
 226         if (!irq_remapping_enabled ||
 227             !remap_ops ||
 228             !remap_ops->disable)
 229                 return;
 230
 231         remap_ops->disable();
 232 }
 233
 234 int irq_remapping_reenable(int mode)
 235 {
 236         if (!irq_remapping_enabled ||
 237             !remap_ops ||
 238             !remap_ops->reenable)
 239                 return 0;
 240
 241         return remap_ops->reenable(mode);
 242 }
 243
 244 int __init irq_remap_enable_fault_handling(void)
 245 {
 246         if (!irq_remapping_enabled)
 247                 return 0;
 248
 249         if (!remap_ops || !remap_ops->enable_faulting)
 250                 return -ENODEV;
 251
 252         return remap_ops->enable_faulting();
 253 }
 254
 255 int setup_ioapic_remapped_entry(int irq,
 256                                 struct IO_APIC_route_entry *entry,
 257                                 unsigned int destination, int vector,
 258                                 struct io_apic_irq_attr *attr)
 259 {
 260         if (!remap_ops || !remap_ops->setup_ioapic_entry)
 261                 return -ENODEV;
 262
 263         return remap_ops->setup_ioapic_entry(irq, entry, destination,
 264                                              vector, attr);
 265 }
 266
 267 int set_remapped_irq_affinity(struct irq_data *data, const struct cpumask *mask,
 268                               bool force)
 269 {
 270         if (!config_enabled(CONFIG_SMP) || !remap_ops ||
 271             !remap_ops->set_affinity)
 272                 return 0;
 273
 274         return remap_ops->set_affinity(data, mask, force);
 275 }
 276
 277 void free_remapped_irq(int irq)
 278 {
 279         if (!remap_ops || !remap_ops->free_irq)
 280                 return;
 281
 282         remap_ops->free_irq(irq);
 283 }
 284
 285 void compose_remapped_msi_msg(struct pci_dev *pdev,
 286                               unsigned int irq, unsigned int dest,
 287                               struct msi_msg *msg, u8 hpet_id)
 288 {
 289         if (!remap_ops || !remap_ops->compose_msi_msg)
 290                 return;
 291
 292         remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 293 }
 294
 295 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
 296 {
 297         if (!remap_ops || !remap_ops->msi_alloc_irq)
 298                 return -ENODEV;
 299
 300         return remap_ops->msi_alloc_irq(pdev, irq, nvec);
 301 }
 302
 303 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
 304                                   int index, int sub_handle)
 305 {
 306         if (!remap_ops || !remap_ops->msi_setup_irq)
 307                 return -ENODEV;
 308
 309         return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle);
 310 }
 311
 312 int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
 313 {
 314         if (!remap_ops || !remap_ops->setup_hpet_msi)
 315                 return -ENODEV;
 316
 317         return remap_ops->setup_hpet_msi(irq, id);
 318 }