linux/drivers/iommu/irq_remapping.c
<<
>>
Prefs
   1#include <linux/seq_file.h>
   2#include <linux/cpumask.h>
   3#include <linux/kernel.h>
   4#include <linux/string.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
  18int irq_remapping_enabled;
  19
  20int disable_irq_remap;
  21int irq_remap_broken;
  22int disable_sourceid_checking;
  23int no_x2apic_optout;
  24
  25static struct irq_remap_ops *remap_ops;
  26
  27static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec);
  28static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
  29                                  int index, int sub_handle);
  30static int set_remapped_irq_affinity(struct irq_data *data,
  31                                     const struct cpumask *mask,
  32                                     bool force);
  33
  34static bool irq_remapped(struct irq_cfg *cfg)
  35{
  36        return (cfg->remapped == 1);
  37}
  38
  39static 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
  52static int do_setup_msi_irqs(struct pci_dev *dev, int nvec)
  53{
  54        int node, ret, sub_handle, nvec_pow2, index = 0;
  55        unsigned int irq;
  56        struct msi_desc *msidesc;
  57
  58        WARN_ON(!list_is_singular(&dev->msi_list));
  59        msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
  60        WARN_ON(msidesc->irq);
  61        WARN_ON(msidesc->msi_attrib.multiple);
  62        WARN_ON(msidesc->nvec_used);
  63
  64        node = dev_to_node(&dev->dev);
  65        irq = __create_irqs(get_nr_irqs_gsi(), nvec, node);
  66        if (irq == 0)
  67                return -ENOSPC;
  68
  69        nvec_pow2 = __roundup_pow_of_two(nvec);
  70        msidesc->nvec_used = nvec;
  71        msidesc->msi_attrib.multiple = ilog2(nvec_pow2);
  72        for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
  73                if (!sub_handle) {
  74                        index = msi_alloc_remapped_irq(dev, irq, nvec_pow2);
  75                        if (index < 0) {
  76                                ret = index;
  77                                goto error;
  78                        }
  79                } else {
  80                        ret = msi_setup_remapped_irq(dev, irq + sub_handle,
  81                                                     index, sub_handle);
  82                        if (ret < 0)
  83                                goto error;
  84                }
  85                ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
  86                if (ret < 0)
  87                        goto error;
  88        }
  89        return 0;
  90
  91error:
  92        destroy_irqs(irq, nvec);
  93
  94        /*
  95         * Restore altered MSI descriptor fields and prevent just destroyed
  96         * IRQs from tearing down again in default_teardown_msi_irqs()
  97         */
  98        msidesc->irq = 0;
  99        msidesc->nvec_used = 0;
 100        msidesc->msi_attrib.multiple = 0;
 101
 102        return ret;
 103}
 104
 105static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
 106{
 107        int node, ret, sub_handle, index = 0;
 108        struct msi_desc *msidesc;
 109        unsigned int irq;
 110
 111        node            = dev_to_node(&dev->dev);
 112        irq             = get_nr_irqs_gsi();
 113        sub_handle      = 0;
 114
 115        list_for_each_entry(msidesc, &dev->msi_list, list) {
 116
 117                irq = create_irq_nr(irq, node);
 118                if (irq == 0)
 119                        return -1;
 120
 121                if (sub_handle == 0)
 122                        ret = index = msi_alloc_remapped_irq(dev, irq, nvec);
 123                else
 124                        ret = msi_setup_remapped_irq(dev, irq, index, sub_handle);
 125
 126                if (ret < 0)
 127                        goto error;
 128
 129                ret = setup_msi_irq(dev, msidesc, irq, 0);
 130                if (ret < 0)
 131                        goto error;
 132
 133                sub_handle += 1;
 134                irq        += 1;
 135        }
 136
 137        return 0;
 138
 139error:
 140        destroy_irq(irq);
 141        return ret;
 142}
 143
 144static int irq_remapping_setup_msi_irqs(struct pci_dev *dev,
 145                                        int nvec, int type)
 146{
 147        if (type == PCI_CAP_ID_MSI)
 148                return do_setup_msi_irqs(dev, nvec);
 149        else
 150                return do_setup_msix_irqs(dev, nvec);
 151}
 152
 153void eoi_ioapic_pin_remapped(int apic, int pin, int vector)
 154{
 155        /*
 156         * Intr-remapping uses pin number as the virtual vector
 157         * in the RTE. Actual vector is programmed in
 158         * intr-remapping table entry. Hence for the io-apic
 159         * EOI we use the pin number.
 160         */
 161        io_apic_eoi(apic, pin);
 162}
 163
 164static void __init irq_remapping_modify_x86_ops(void)
 165{
 166        x86_io_apic_ops.disable         = irq_remapping_disable_io_apic;
 167        x86_io_apic_ops.set_affinity    = set_remapped_irq_affinity;
 168        x86_io_apic_ops.setup_entry     = setup_ioapic_remapped_entry;
 169        x86_io_apic_ops.eoi_ioapic_pin  = eoi_ioapic_pin_remapped;
 170        x86_msi.setup_msi_irqs          = irq_remapping_setup_msi_irqs;
 171        x86_msi.setup_hpet_msi          = setup_hpet_msi_remapped;
 172        x86_msi.compose_msi_msg         = compose_remapped_msi_msg;
 173}
 174
 175static __init int setup_nointremap(char *str)
 176{
 177        disable_irq_remap = 1;
 178        return 0;
 179}
 180early_param("nointremap", setup_nointremap);
 181
 182static __init int setup_irqremap(char *str)
 183{
 184        if (!str)
 185                return -EINVAL;
 186
 187        while (*str) {
 188                if (!strncmp(str, "on", 2))
 189                        disable_irq_remap = 0;
 190                else if (!strncmp(str, "off", 3))
 191                        disable_irq_remap = 1;
 192                else if (!strncmp(str, "nosid", 5))
 193                        disable_sourceid_checking = 1;
 194                else if (!strncmp(str, "no_x2apic_optout", 16))
 195                        no_x2apic_optout = 1;
 196
 197                str += strcspn(str, ",");
 198                while (*str == ',')
 199                        str++;
 200        }
 201
 202        return 0;
 203}
 204early_param("intremap", setup_irqremap);
 205
 206void __init setup_irq_remapping_ops(void)
 207{
 208        remap_ops = &intel_irq_remap_ops;
 209
 210#ifdef CONFIG_AMD_IOMMU
 211        if (amd_iommu_irq_ops.prepare() == 0)
 212                remap_ops = &amd_iommu_irq_ops;
 213#endif
 214}
 215
 216void set_irq_remapping_broken(void)
 217{
 218        irq_remap_broken = 1;
 219}
 220
 221int irq_remapping_supported(void)
 222{
 223        if (disable_irq_remap)
 224                return 0;
 225
 226        if (!remap_ops || !remap_ops->supported)
 227                return 0;
 228
 229        return remap_ops->supported();
 230}
 231
 232int __init irq_remapping_prepare(void)
 233{
 234        if (!remap_ops || !remap_ops->prepare)
 235                return -ENODEV;
 236
 237        return remap_ops->prepare();
 238}
 239
 240int __init irq_remapping_enable(void)
 241{
 242        int ret;
 243
 244        if (!remap_ops || !remap_ops->enable)
 245                return -ENODEV;
 246
 247        ret = remap_ops->enable();
 248
 249        if (irq_remapping_enabled)
 250                irq_remapping_modify_x86_ops();
 251
 252        return ret;
 253}
 254
 255void irq_remapping_disable(void)
 256{
 257        if (!irq_remapping_enabled ||
 258            !remap_ops ||
 259            !remap_ops->disable)
 260                return;
 261
 262        remap_ops->disable();
 263}
 264
 265int irq_remapping_reenable(int mode)
 266{
 267        if (!irq_remapping_enabled ||
 268            !remap_ops ||
 269            !remap_ops->reenable)
 270                return 0;
 271
 272        return remap_ops->reenable(mode);
 273}
 274
 275int __init irq_remap_enable_fault_handling(void)
 276{
 277        if (!irq_remapping_enabled)
 278                return 0;
 279
 280        if (!remap_ops || !remap_ops->enable_faulting)
 281                return -ENODEV;
 282
 283        return remap_ops->enable_faulting();
 284}
 285
 286int setup_ioapic_remapped_entry(int irq,
 287                                struct IO_APIC_route_entry *entry,
 288                                unsigned int destination, int vector,
 289                                struct io_apic_irq_attr *attr)
 290{
 291        if (!remap_ops || !remap_ops->setup_ioapic_entry)
 292                return -ENODEV;
 293
 294        return remap_ops->setup_ioapic_entry(irq, entry, destination,
 295                                             vector, attr);
 296}
 297
 298int set_remapped_irq_affinity(struct irq_data *data, const struct cpumask *mask,
 299                              bool force)
 300{
 301        if (!config_enabled(CONFIG_SMP) || !remap_ops ||
 302            !remap_ops->set_affinity)
 303                return 0;
 304
 305        return remap_ops->set_affinity(data, mask, force);
 306}
 307
 308void free_remapped_irq(int irq)
 309{
 310        struct irq_cfg *cfg = irq_get_chip_data(irq);
 311
 312        if (!remap_ops || !remap_ops->free_irq)
 313                return;
 314
 315        if (irq_remapped(cfg))
 316                remap_ops->free_irq(irq);
 317}
 318
 319void compose_remapped_msi_msg(struct pci_dev *pdev,
 320                              unsigned int irq, unsigned int dest,
 321                              struct msi_msg *msg, u8 hpet_id)
 322{
 323        struct irq_cfg *cfg = irq_get_chip_data(irq);
 324
 325        if (!irq_remapped(cfg))
 326                native_compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 327        else if (remap_ops && remap_ops->compose_msi_msg)
 328                remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 329}
 330
 331static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
 332{
 333        if (!remap_ops || !remap_ops->msi_alloc_irq)
 334                return -ENODEV;
 335
 336        return remap_ops->msi_alloc_irq(pdev, irq, nvec);
 337}
 338
 339static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
 340                                  int index, int sub_handle)
 341{
 342        if (!remap_ops || !remap_ops->msi_setup_irq)
 343                return -ENODEV;
 344
 345        return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle);
 346}
 347
 348int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
 349{
 350        if (!remap_ops || !remap_ops->setup_hpet_msi)
 351                return -ENODEV;
 352
 353        return remap_ops->setup_hpet_msi(irq, id);
 354}
 355
 356void panic_if_irq_remap(const char *msg)
 357{
 358        if (irq_remapping_enabled)
 359                panic(msg);
 360}
 361
 362static void ir_ack_apic_edge(struct irq_data *data)
 363{
 364        ack_APIC_irq();
 365}
 366
 367static void ir_ack_apic_level(struct irq_data *data)
 368{
 369        ack_APIC_irq();
 370        eoi_ioapic_irq(data->irq, data->chip_data);
 371}
 372
 373static void ir_print_prefix(struct irq_data *data, struct seq_file *p)
 374{
 375        seq_printf(p, " IR-%s", data->chip->name);
 376}
 377
 378void irq_remap_modify_chip_defaults(struct irq_chip *chip)
 379{
 380        chip->irq_print_chip = ir_print_prefix;
 381        chip->irq_ack = ir_ack_apic_edge;
 382        chip->irq_eoi = ir_ack_apic_level;
 383        chip->irq_set_affinity = x86_io_apic_ops.set_affinity;
 384}
 385
 386bool setup_remapped_irq(int irq, struct irq_cfg *cfg, struct irq_chip *chip)
 387{
 388        if (!irq_remapped(cfg))
 389                return false;
 390        irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
 391        irq_remap_modify_chip_defaults(chip);
 392        return true;
 393}
 394
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.