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 #include <asm/hpet.h> 16 17 #include "irq_remapping.h" 18 19 int irq_remapping_enabled; 20 int irq_remap_broken; 21 int disable_sourceid_checking; 22 int no_x2apic_optout; 23 24 static int disable_irq_remap; 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 bool irq_remapped(struct irq_cfg *cfg) 35 { 36 return (cfg->remapped == 1); 37 } 38 39 static 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 52 static int do_setup_msi_irqs(struct pci_dev *dev, int nvec) 53 { 54 int ret, sub_handle, nvec_pow2, index = 0; 55 unsigned int irq; 56 struct msi_desc *msidesc; 57 58 msidesc = list_entry(dev->msi_list.next, struct msi_desc, list); 59 60 irq = irq_alloc_hwirqs(nvec, dev_to_node(&dev->dev)); 61 if (irq == 0) 62 return -ENOSPC; 63 64 nvec_pow2 = __roundup_pow_of_two(nvec); 65 for (sub_handle = 0; sub_handle < nvec; sub_handle++) { 66 if (!sub_handle) { 67 index = msi_alloc_remapped_irq(dev, irq, nvec_pow2); 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 irq_free_hwirqs(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 93 return ret; 94 } 95 96 static int do_setup_msix_irqs(struct pci_dev *dev, int nvec) 97 { 98 int node, ret, sub_handle, index = 0; 99 struct msi_desc *msidesc; 100 unsigned int irq; 101 102 node = dev_to_node(&dev->dev); 103 sub_handle = 0; 104 105 list_for_each_entry(msidesc, &dev->msi_list, list) { 106 107 irq = irq_alloc_hwirq(node); 108 if (irq == 0) 109 return -1; 110 111 if (sub_handle == 0) 112 ret = index = msi_alloc_remapped_irq(dev, irq, nvec); 113 else 114 ret = msi_setup_remapped_irq(dev, irq, index, sub_handle); 115 116 if (ret < 0) 117 goto error; 118 119 ret = setup_msi_irq(dev, msidesc, irq, 0); 120 if (ret < 0) 121 goto error; 122 123 sub_handle += 1; 124 irq += 1; 125 } 126 127 return 0; 128 129 error: 130 irq_free_hwirq(irq); 131 return ret; 132 } 133 134 static int irq_remapping_setup_msi_irqs(struct pci_dev *dev, 135 int nvec, int type) 136 { 137 if (type == PCI_CAP_ID_MSI) 138 return do_setup_msi_irqs(dev, nvec); 139 else 140 return do_setup_msix_irqs(dev, nvec); 141 } 142 143 static void eoi_ioapic_pin_remapped(int apic, int pin, int vector) 144 { 145 /* 146 * Intr-remapping uses pin number as the virtual vector 147 * in the RTE. Actual vector is programmed in 148 * intr-remapping table entry. Hence for the io-apic 149 * EOI we use the pin number. 150 */ 151 io_apic_eoi(apic, pin); 152 } 153 154 static void __init irq_remapping_modify_x86_ops(void) 155 { 156 x86_io_apic_ops.disable = irq_remapping_disable_io_apic; 157 x86_io_apic_ops.set_affinity = set_remapped_irq_affinity; 158 x86_io_apic_ops.setup_entry = setup_ioapic_remapped_entry; 159 x86_io_apic_ops.eoi_ioapic_pin = eoi_ioapic_pin_remapped; 160 x86_msi.setup_msi_irqs = irq_remapping_setup_msi_irqs; 161 x86_msi.setup_hpet_msi = setup_hpet_msi_remapped; 162 x86_msi.compose_msi_msg = compose_remapped_msi_msg; 163 } 164 165 static __init int setup_nointremap(char *str) 166 { 167 disable_irq_remap = 1; 168 return 0; 169 } 170 early_param("nointremap", setup_nointremap); 171 172 static __init int setup_irqremap(char *str) 173 { 174 if (!str) 175 return -EINVAL; 176 177 while (*str) { 178 if (!strncmp(str, "on", 2)) 179 disable_irq_remap = 0; 180 else if (!strncmp(str, "off", 3)) 181 disable_irq_remap = 1; 182 else if (!strncmp(str, "nosid", 5)) 183 disable_sourceid_checking = 1; 184 else if (!strncmp(str, "no_x2apic_optout", 16)) 185 no_x2apic_optout = 1; 186 187 str += strcspn(str, ","); 188 while (*str == ',') 189 str++; 190 } 191 192 return 0; 193 } 194 early_param("intremap", setup_irqremap); 195 196 void set_irq_remapping_broken(void) 197 { 198 irq_remap_broken = 1; 199 } 200 201 int __init irq_remapping_prepare(void) 202 { 203 if (disable_irq_remap) 204 return -ENOSYS; 205 206 if (intel_irq_remap_ops.prepare() == 0) 207 remap_ops = &intel_irq_remap_ops; 208 else if (IS_ENABLED(CONFIG_AMD_IOMMU) && 209 amd_iommu_irq_ops.prepare() == 0) 210 remap_ops = &amd_iommu_irq_ops; 211 else 212 return -ENOSYS; 213 214 return 0; 215 } 216 217 int __init irq_remapping_enable(void) 218 { 219 int ret; 220 221 if (!remap_ops->enable) 222 return -ENODEV; 223 224 ret = remap_ops->enable(); 225 226 if (irq_remapping_enabled) 227 irq_remapping_modify_x86_ops(); 228 229 return ret; 230 } 231 232 void irq_remapping_disable(void) 233 { 234 if (irq_remapping_enabled && remap_ops->disable) 235 remap_ops->disable(); 236 } 237 238 int irq_remapping_reenable(int mode) 239 { 240 if (irq_remapping_enabled && remap_ops->reenable) 241 return remap_ops->reenable(mode); 242 243 return 0; 244 } 245 246 int __init irq_remap_enable_fault_handling(void) 247 { 248 if (!irq_remapping_enabled) 249 return 0; 250 251 if (!remap_ops->enable_faulting) 252 return -ENODEV; 253 254 return remap_ops->enable_faulting(); 255 } 256 257 int setup_ioapic_remapped_entry(int irq, 258 struct IO_APIC_route_entry *entry, 259 unsigned int destination, int vector, 260 struct io_apic_irq_attr *attr) 261 { 262 if (!remap_ops->setup_ioapic_entry) 263 return -ENODEV; 264 265 return remap_ops->setup_ioapic_entry(irq, entry, destination, 266 vector, attr); 267 } 268 269 static int set_remapped_irq_affinity(struct irq_data *data, 270 const struct cpumask *mask, bool force) 271 { 272 if (!config_enabled(CONFIG_SMP) || !remap_ops->set_affinity) 273 return 0; 274 275 return remap_ops->set_affinity(data, mask, force); 276 } 277 278 void free_remapped_irq(int irq) 279 { 280 struct irq_cfg *cfg = irq_cfg(irq); 281 282 if (irq_remapped(cfg) && remap_ops->free_irq) 283 remap_ops->free_irq(irq); 284 } 285 286 void compose_remapped_msi_msg(struct pci_dev *pdev, 287 unsigned int irq, unsigned int dest, 288 struct msi_msg *msg, u8 hpet_id) 289 { 290 struct irq_cfg *cfg = irq_cfg(irq); 291 292 if (!irq_remapped(cfg)) 293 native_compose_msi_msg(pdev, irq, dest, msg, hpet_id); 294 else if (remap_ops->compose_msi_msg) 295 remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id); 296 } 297 298 static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec) 299 { 300 if (!remap_ops->msi_alloc_irq) 301 return -ENODEV; 302 303 return remap_ops->msi_alloc_irq(pdev, irq, nvec); 304 } 305 306 static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq, 307 int index, int sub_handle) 308 { 309 if (!remap_ops->msi_setup_irq) 310 return -ENODEV; 311 312 return remap_ops->msi_setup_irq(pdev, irq, index, sub_handle); 313 } 314 315 int setup_hpet_msi_remapped(unsigned int irq, unsigned int id) 316 { 317 int ret; 318 319 if (!remap_ops->alloc_hpet_msi) 320 return -ENODEV; 321 322 ret = remap_ops->alloc_hpet_msi(irq, id); 323 if (ret) 324 return -EINVAL; 325 326 return default_setup_hpet_msi(irq, id); 327 } 328 329 void panic_if_irq_remap(const char *msg) 330 { 331 if (irq_remapping_enabled) 332 panic(msg); 333 } 334 335 static void ir_ack_apic_edge(struct irq_data *data) 336 { 337 ack_APIC_irq(); 338 } 339 340 static void ir_ack_apic_level(struct irq_data *data) 341 { 342 ack_APIC_irq(); 343 eoi_ioapic_irq(data->irq, irqd_cfg(data)); 344 } 345 346 static void ir_print_prefix(struct irq_data *data, struct seq_file *p) 347 { 348 seq_printf(p, " IR-%s", data->chip->name); 349 } 350 351 void irq_remap_modify_chip_defaults(struct irq_chip *chip) 352 { 353 chip->irq_print_chip = ir_print_prefix; 354 chip->irq_ack = ir_ack_apic_edge; 355 chip->irq_eoi = ir_ack_apic_level; 356 chip->irq_set_affinity = x86_io_apic_ops.set_affinity; 357 } 358 359 bool setup_remapped_irq(int irq, struct irq_cfg *cfg, struct irq_chip *chip) 360 { 361 if (!irq_remapped(cfg)) 362 return false; 363 irq_set_status_flags(irq, IRQ_MOVE_PCNTXT); 364 irq_remap_modify_chip_defaults(chip); 365 return true; 366 } 367