1 // SPDX-License-Identifier: GPL-2.0-only 2 #include <xen/xen.h> 3 #include <xen/events.h> 4 #include <xen/grant_table.h> 5 #include <xen/hvm.h> 6 #include <xen/interface/vcpu.h> 7 #include <xen/interface/xen.h> 8 #include <xen/interface/memory.h> 9 #include <xen/interface/hvm/params.h> 10 #include <xen/features.h> 11 #include <xen/platform_pci.h> 12 #include <xen/xenbus.h> 13 #include <xen/page.h> 14 #include <xen/interface/sched.h> 15 #include <xen/xen-ops.h> 16 #include <asm/xen/hypervisor.h> 17 #include <asm/xen/hypercall.h> 18 #include <asm/system_misc.h> 19 #include <asm/efi.h> 20 #include <linux/interrupt.h> 21 #include <linux/irqreturn.h> 22 #include <linux/module.h> 23 #include <linux/of.h> 24 #include <linux/of_fdt.h> 25 #include <linux/of_irq.h> 26 #include <linux/of_address.h> 27 #include <linux/cpuidle.h> 28 #include <linux/cpufreq.h> 29 #include <linux/cpu.h> 30 #include <linux/console.h> 31 #include <linux/pvclock_gtod.h> 32 #include <linux/time64.h> 33 #include <linux/timekeeping.h> 34 #include <linux/timekeeper_internal.h> 35 #include <linux/acpi.h> 36 37 #include <linux/mm.h> 38 39 static struct start_info _xen_start_info; 40 struct start_info *xen_start_info = &_xen_start_info; 41 EXPORT_SYMBOL(xen_start_info); 42 43 enum xen_domain_type xen_domain_type = XEN_NATIVE; 44 EXPORT_SYMBOL(xen_domain_type); 45 46 struct shared_info xen_dummy_shared_info; 47 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; 48 49 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); 50 static struct vcpu_info __percpu *xen_vcpu_info; 51 52 /* Linux <-> Xen vCPU id mapping */ 53 DEFINE_PER_CPU(uint32_t, xen_vcpu_id); 54 EXPORT_PER_CPU_SYMBOL(xen_vcpu_id); 55 56 /* These are unused until we support booting "pre-ballooned" */ 57 unsigned long xen_released_pages; 58 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; 59 60 static __read_mostly unsigned int xen_events_irq; 61 62 uint32_t xen_start_flags; 63 EXPORT_SYMBOL(xen_start_flags); 64 65 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, 66 int nr, struct page **pages) 67 { 68 return xen_xlate_unmap_gfn_range(vma, nr, pages); 69 } 70 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); 71 72 static void xen_read_wallclock(struct timespec64 *ts) 73 { 74 u32 version; 75 struct timespec64 now, ts_monotonic; 76 struct shared_info *s = HYPERVISOR_shared_info; 77 struct pvclock_wall_clock *wall_clock = &(s->wc); 78 79 /* get wallclock at system boot */ 80 do { 81 version = wall_clock->version; 82 rmb(); /* fetch version before time */ 83 now.tv_sec = ((uint64_t)wall_clock->sec_hi << 32) | wall_clock->sec; 84 now.tv_nsec = wall_clock->nsec; 85 rmb(); /* fetch time before checking version */ 86 } while ((wall_clock->version & 1) || (version != wall_clock->version)); 87 88 /* time since system boot */ 89 ktime_get_ts64(&ts_monotonic); 90 *ts = timespec64_add(now, ts_monotonic); 91 } 92 93 static int xen_pvclock_gtod_notify(struct notifier_block *nb, 94 unsigned long was_set, void *priv) 95 { 96 /* Protected by the calling core code serialization */ 97 static struct timespec64 next_sync; 98 99 struct xen_platform_op op; 100 struct timespec64 now, system_time; 101 struct timekeeper *tk = priv; 102 103 now.tv_sec = tk->xtime_sec; 104 now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); 105 system_time = timespec64_add(now, tk->wall_to_monotonic); 106 107 /* 108 * We only take the expensive HV call when the clock was set 109 * or when the 11 minutes RTC synchronization time elapsed. 110 */ 111 if (!was_set && timespec64_compare(&now, &next_sync) < 0) 112 return NOTIFY_OK; 113 114 op.cmd = XENPF_settime64; 115 op.u.settime64.mbz = 0; 116 op.u.settime64.secs = now.tv_sec; 117 op.u.settime64.nsecs = now.tv_nsec; 118 op.u.settime64.system_time = timespec64_to_ns(&system_time); 119 (void)HYPERVISOR_platform_op(&op); 120 121 /* 122 * Move the next drift compensation time 11 minutes 123 * ahead. That's emulating the sync_cmos_clock() update for 124 * the hardware RTC. 125 */ 126 next_sync = now; 127 next_sync.tv_sec += 11 * 60; 128 129 return NOTIFY_OK; 130 } 131 132 static struct notifier_block xen_pvclock_gtod_notifier = { 133 .notifier_call = xen_pvclock_gtod_notify, 134 }; 135 136 static int xen_starting_cpu(unsigned int cpu) 137 { 138 struct vcpu_register_vcpu_info info; 139 struct vcpu_info *vcpup; 140 int err; 141 142 /* 143 * VCPUOP_register_vcpu_info cannot be called twice for the same 144 * vcpu, so if vcpu_info is already registered, just get out. This 145 * can happen with cpu-hotplug. 146 */ 147 if (per_cpu(xen_vcpu, cpu) != NULL) 148 goto after_register_vcpu_info; 149 150 pr_info("Xen: initializing cpu%d\n", cpu); 151 vcpup = per_cpu_ptr(xen_vcpu_info, cpu); 152 153 info.mfn = percpu_to_gfn(vcpup); 154 info.offset = xen_offset_in_page(vcpup); 155 156 err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, xen_vcpu_nr(cpu), 157 &info); 158 BUG_ON(err); 159 per_cpu(xen_vcpu, cpu) = vcpup; 160 161 if (!xen_kernel_unmapped_at_usr()) 162 xen_setup_runstate_info(cpu); 163 164 after_register_vcpu_info: 165 enable_percpu_irq(xen_events_irq, 0); 166 return 0; 167 } 168 169 static int xen_dying_cpu(unsigned int cpu) 170 { 171 disable_percpu_irq(xen_events_irq); 172 return 0; 173 } 174 175 void xen_reboot(int reason) 176 { 177 struct sched_shutdown r = { .reason = reason }; 178 int rc; 179 180 rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r); 181 BUG_ON(rc); 182 } 183 184 static void xen_restart(enum reboot_mode reboot_mode, const char *cmd) 185 { 186 xen_reboot(SHUTDOWN_reboot); 187 } 188 189 190 static void xen_power_off(void) 191 { 192 xen_reboot(SHUTDOWN_poweroff); 193 } 194 195 static irqreturn_t xen_arm_callback(int irq, void *arg) 196 { 197 xen_hvm_evtchn_do_upcall(); 198 return IRQ_HANDLED; 199 } 200 201 static __initdata struct { 202 const char *compat; 203 const char *prefix; 204 const char *version; 205 bool found; 206 } hyper_node = {"xen,xen", "xen,xen-", NULL, false}; 207 208 static int __init fdt_find_hyper_node(unsigned long node, const char *uname, 209 int depth, void *data) 210 { 211 const void *s = NULL; 212 int len; 213 214 if (depth != 1 || strcmp(uname, "hypervisor") != 0) 215 return 0; 216 217 if (of_flat_dt_is_compatible(node, hyper_node.compat)) 218 hyper_node.found = true; 219 220 s = of_get_flat_dt_prop(node, "compatible", &len); 221 if (strlen(hyper_node.prefix) + 3 < len && 222 !strncmp(hyper_node.prefix, s, strlen(hyper_node.prefix))) 223 hyper_node.version = s + strlen(hyper_node.prefix); 224 225 /* 226 * Check if Xen supports EFI by checking whether there is the 227 * "/hypervisor/uefi" node in DT. If so, runtime services are available 228 * through proxy functions (e.g. in case of Xen dom0 EFI implementation 229 * they call special hypercall which executes relevant EFI functions) 230 * and that is why they are always enabled. 231 */ 232 if (IS_ENABLED(CONFIG_XEN_EFI)) { 233 if ((of_get_flat_dt_subnode_by_name(node, "uefi") > 0) && 234 !efi_runtime_disabled()) 235 set_bit(EFI_RUNTIME_SERVICES, &efi.flags); 236 } 237 238 return 0; 239 } 240 241 /* 242 * see Documentation/devicetree/bindings/arm/xen.txt for the 243 * documentation of the Xen Device Tree format. 244 */ 245 void __init xen_early_init(void) 246 { 247 of_scan_flat_dt(fdt_find_hyper_node, NULL); 248 if (!hyper_node.found) { 249 pr_debug("No Xen support\n"); 250 return; 251 } 252 253 if (hyper_node.version == NULL) { 254 pr_debug("Xen version not found\n"); 255 return; 256 } 257 258 pr_info("Xen %s support found\n", hyper_node.version); 259 260 xen_domain_type = XEN_HVM_DOMAIN; 261 262 xen_setup_features(); 263 264 if (xen_feature(XENFEAT_dom0)) 265 xen_start_flags |= SIF_INITDOMAIN|SIF_PRIVILEGED; 266 267 if (!console_set_on_cmdline && !xen_initial_domain()) 268 add_preferred_console("hvc", 0, NULL); 269 } 270 271 static void __init xen_acpi_guest_init(void) 272 { 273 #ifdef CONFIG_ACPI 274 struct xen_hvm_param a; 275 int interrupt, trigger, polarity; 276 277 a.domid = DOMID_SELF; 278 a.index = HVM_PARAM_CALLBACK_IRQ; 279 280 if (HYPERVISOR_hvm_op(HVMOP_get_param, &a) 281 || (a.value >> 56) != HVM_PARAM_CALLBACK_TYPE_PPI) { 282 xen_events_irq = 0; 283 return; 284 } 285 286 interrupt = a.value & 0xff; 287 trigger = ((a.value >> 8) & 0x1) ? ACPI_EDGE_SENSITIVE 288 : ACPI_LEVEL_SENSITIVE; 289 polarity = ((a.value >> 8) & 0x2) ? ACPI_ACTIVE_LOW 290 : ACPI_ACTIVE_HIGH; 291 xen_events_irq = acpi_register_gsi(NULL, interrupt, trigger, polarity); 292 #endif 293 } 294 295 static void __init xen_dt_guest_init(void) 296 { 297 struct device_node *xen_node; 298 299 xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); 300 if (!xen_node) { 301 pr_err("Xen support was detected before, but it has disappeared\n"); 302 return; 303 } 304 305 xen_events_irq = irq_of_parse_and_map(xen_node, 0); 306 } 307 308 static int __init xen_guest_init(void) 309 { 310 struct xen_add_to_physmap xatp; 311 struct shared_info *shared_info_page = NULL; 312 int cpu; 313 314 if (!xen_domain()) 315 return 0; 316 317 if (!acpi_disabled) 318 xen_acpi_guest_init(); 319 else 320 xen_dt_guest_init(); 321 322 if (!xen_events_irq) { 323 pr_err("Xen event channel interrupt not found\n"); 324 return -ENODEV; 325 } 326 327 /* 328 * The fdt parsing codes have set EFI_RUNTIME_SERVICES if Xen EFI 329 * parameters are found. Force enable runtime services. 330 */ 331 if (efi_enabled(EFI_RUNTIME_SERVICES)) 332 xen_efi_runtime_setup(); 333 334 shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL); 335 336 if (!shared_info_page) { 337 pr_err("not enough memory\n"); 338 return -ENOMEM; 339 } 340 xatp.domid = DOMID_SELF; 341 xatp.idx = 0; 342 xatp.space = XENMAPSPACE_shared_info; 343 xatp.gpfn = virt_to_gfn(shared_info_page); 344 if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) 345 BUG(); 346 347 HYPERVISOR_shared_info = (struct shared_info *)shared_info_page; 348 349 /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info 350 * page, we use it in the event channel upcall and in some pvclock 351 * related functions. 352 * The shared info contains exactly 1 CPU (the boot CPU). The guest 353 * is required to use VCPUOP_register_vcpu_info to place vcpu info 354 * for secondary CPUs as they are brought up. 355 * For uniformity we use VCPUOP_register_vcpu_info even on cpu0. 356 */ 357 xen_vcpu_info = alloc_percpu(struct vcpu_info); 358 if (xen_vcpu_info == NULL) 359 return -ENOMEM; 360 361 /* Direct vCPU id mapping for ARM guests. */ 362 for_each_possible_cpu(cpu) 363 per_cpu(xen_vcpu_id, cpu) = cpu; 364 365 xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); 366 if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, 367 &xen_auto_xlat_grant_frames.vaddr, 368 xen_auto_xlat_grant_frames.count)) { 369 free_percpu(xen_vcpu_info); 370 return -ENOMEM; 371 } 372 gnttab_init(); 373 374 /* 375 * Making sure board specific code will not set up ops for 376 * cpu idle and cpu freq. 377 */ 378 disable_cpuidle(); 379 disable_cpufreq(); 380 381 xen_init_IRQ(); 382 383 if (request_percpu_irq(xen_events_irq, xen_arm_callback, 384 "events", &xen_vcpu)) { 385 pr_err("Error request IRQ %d\n", xen_events_irq); 386 return -EINVAL; 387 } 388 389 if (!xen_kernel_unmapped_at_usr()) 390 xen_time_setup_guest(); 391 392 if (xen_initial_domain()) 393 pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier); 394 395 return cpuhp_setup_state(CPUHP_AP_ARM_XEN_STARTING, 396 "arm/xen:starting", xen_starting_cpu, 397 xen_dying_cpu); 398 } 399 early_initcall(xen_guest_init); 400 401 static int __init xen_pm_init(void) 402 { 403 if (!xen_domain()) 404 return -ENODEV; 405 406 pm_power_off = xen_power_off; 407 arm_pm_restart = xen_restart; 408 if (!xen_initial_domain()) { 409 struct timespec64 ts; 410 xen_read_wallclock(&ts); 411 do_settimeofday64(&ts); 412 } 413 414 return 0; 415 } 416 late_initcall(xen_pm_init); 417 418 419 /* empty stubs */ 420 void xen_arch_pre_suspend(void) { } 421 void xen_arch_post_suspend(int suspend_cancelled) { } 422 void xen_timer_resume(void) { } 423 void xen_arch_resume(void) { } 424 void xen_arch_suspend(void) { } 425 426 427 /* In the hypercall.S file. */ 428 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op); 429 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op); 430 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version); 431 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io); 432 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op); 433 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op); 434 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op); 435 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op); 436 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op); 437 EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op); 438 EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op_raw); 439 EXPORT_SYMBOL_GPL(HYPERVISOR_multicall); 440 EXPORT_SYMBOL_GPL(HYPERVISOR_vm_assist); 441 EXPORT_SYMBOL_GPL(HYPERVISOR_dm_op); 442 EXPORT_SYMBOL_GPL(privcmd_call); 443