diff options
Diffstat (limited to 'arch/arm/xen/enlighten.c')
| -rw-r--r-- | arch/arm/xen/enlighten.c | 450 |
1 files changed, 450 insertions, 0 deletions
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c new file mode 100644 index 000000000..518c7557f --- /dev/null +++ b/arch/arm/xen/enlighten.c @@ -0,0 +1,450 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include <xen/xen.h> +#include <xen/events.h> +#include <xen/grant_table.h> +#include <xen/hvm.h> +#include <xen/interface/vcpu.h> +#include <xen/interface/xen.h> +#include <xen/interface/memory.h> +#include <xen/interface/hvm/params.h> +#include <xen/features.h> +#include <xen/platform_pci.h> +#include <xen/xenbus.h> +#include <xen/page.h> +#include <xen/interface/sched.h> +#include <xen/xen-ops.h> +#include <asm/xen/hypervisor.h> +#include <asm/xen/hypercall.h> +#include <asm/system_misc.h> +#include <asm/efi.h> +#include <linux/interrupt.h> +#include <linux/irqreturn.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_irq.h> +#include <linux/of_address.h> +#include <linux/cpuidle.h> +#include <linux/cpufreq.h> +#include <linux/cpu.h> +#include <linux/console.h> +#include <linux/pvclock_gtod.h> +#include <linux/time64.h> +#include <linux/timekeeping.h> +#include <linux/timekeeper_internal.h> +#include <linux/acpi.h> + +#include <linux/mm.h> + +static struct start_info _xen_start_info; +struct start_info *xen_start_info = &_xen_start_info; +EXPORT_SYMBOL(xen_start_info); + +enum xen_domain_type xen_domain_type = XEN_NATIVE; +EXPORT_SYMBOL(xen_domain_type); + +struct shared_info xen_dummy_shared_info; +struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info; + +DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu); +static struct vcpu_info __percpu *xen_vcpu_info; + +/* Linux <-> Xen vCPU id mapping */ +DEFINE_PER_CPU(uint32_t, xen_vcpu_id); +EXPORT_PER_CPU_SYMBOL(xen_vcpu_id); + +/* These are unused until we support booting "pre-ballooned" */ +unsigned long xen_released_pages; +struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata; + +static __read_mostly unsigned int xen_events_irq; + +uint32_t xen_start_flags; +EXPORT_SYMBOL(xen_start_flags); + +int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, + int nr, struct page **pages) +{ + return xen_xlate_unmap_gfn_range(vma, nr, pages); +} +EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); + +static void xen_read_wallclock(struct timespec64 *ts) +{ + u32 version; + struct timespec64 now, ts_monotonic; + struct shared_info *s = HYPERVISOR_shared_info; + struct pvclock_wall_clock *wall_clock = &(s->wc); + + /* get wallclock at system boot */ + do { + version = wall_clock->version; + rmb(); /* fetch version before time */ + now.tv_sec = ((uint64_t)wall_clock->sec_hi << 32) | wall_clock->sec; + now.tv_nsec = wall_clock->nsec; + rmb(); /* fetch time before checking version */ + } while ((wall_clock->version & 1) || (version != wall_clock->version)); + + /* time since system boot */ + ktime_get_ts64(&ts_monotonic); + *ts = timespec64_add(now, ts_monotonic); +} + +static int xen_pvclock_gtod_notify(struct notifier_block *nb, + unsigned long was_set, void *priv) +{ + /* Protected by the calling core code serialization */ + static struct timespec64 next_sync; + + struct xen_platform_op op; + struct timespec64 now, system_time; + struct timekeeper *tk = priv; + + now.tv_sec = tk->xtime_sec; + now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift); + system_time = timespec64_add(now, tk->wall_to_monotonic); + + /* + * We only take the expensive HV call when the clock was set + * or when the 11 minutes RTC synchronization time elapsed. + */ + if (!was_set && timespec64_compare(&now, &next_sync) < 0) + return NOTIFY_OK; + + op.cmd = XENPF_settime64; + op.u.settime64.mbz = 0; + op.u.settime64.secs = now.tv_sec; + op.u.settime64.nsecs = now.tv_nsec; + op.u.settime64.system_time = timespec64_to_ns(&system_time); + (void)HYPERVISOR_platform_op(&op); + + /* + * Move the next drift compensation time 11 minutes + * ahead. That's emulating the sync_cmos_clock() update for + * the hardware RTC. + */ + next_sync = now; + next_sync.tv_sec += 11 * 60; + + return NOTIFY_OK; +} + +static struct notifier_block xen_pvclock_gtod_notifier = { + .notifier_call = xen_pvclock_gtod_notify, +}; + +static int xen_starting_cpu(unsigned int cpu) +{ + struct vcpu_register_vcpu_info info; + struct vcpu_info *vcpup; + int err; + + /* + * VCPUOP_register_vcpu_info cannot be called twice for the same + * vcpu, so if vcpu_info is already registered, just get out. This + * can happen with cpu-hotplug. + */ + if (per_cpu(xen_vcpu, cpu) != NULL) + goto after_register_vcpu_info; + + pr_info("Xen: initializing cpu%d\n", cpu); + vcpup = per_cpu_ptr(xen_vcpu_info, cpu); + + info.mfn = percpu_to_gfn(vcpup); + info.offset = xen_offset_in_page(vcpup); + + err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, xen_vcpu_nr(cpu), + &info); + BUG_ON(err); + per_cpu(xen_vcpu, cpu) = vcpup; + +after_register_vcpu_info: + enable_percpu_irq(xen_events_irq, 0); + return 0; +} + +static int xen_dying_cpu(unsigned int cpu) +{ + disable_percpu_irq(xen_events_irq); + return 0; +} + +void xen_reboot(int reason) +{ + struct sched_shutdown r = { .reason = reason }; + int rc; + + rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r); + BUG_ON(rc); +} + +static void xen_restart(enum reboot_mode reboot_mode, const char *cmd) +{ + xen_reboot(SHUTDOWN_reboot); +} + + +static void xen_power_off(void) +{ + xen_reboot(SHUTDOWN_poweroff); +} + +static irqreturn_t xen_arm_callback(int irq, void *arg) +{ + xen_hvm_evtchn_do_upcall(); + return IRQ_HANDLED; +} + +static __initdata struct { + const char *compat; + const char *prefix; + const char *version; + bool found; +} hyper_node = {"xen,xen", "xen,xen-", NULL, false}; + +static int __init fdt_find_hyper_node(unsigned long node, const char *uname, + int depth, void *data) +{ + const void *s = NULL; + int len; + + if (depth != 1 || strcmp(uname, "hypervisor") != 0) + return 0; + + if (of_flat_dt_is_compatible(node, hyper_node.compat)) + hyper_node.found = true; + + s = of_get_flat_dt_prop(node, "compatible", &len); + if (strlen(hyper_node.prefix) + 3 < len && + !strncmp(hyper_node.prefix, s, strlen(hyper_node.prefix))) + hyper_node.version = s + strlen(hyper_node.prefix); + + /* + * Check if Xen supports EFI by checking whether there is the + * "/hypervisor/uefi" node in DT. If so, runtime services are available + * through proxy functions (e.g. in case of Xen dom0 EFI implementation + * they call special hypercall which executes relevant EFI functions) + * and that is why they are always enabled. + */ + if (IS_ENABLED(CONFIG_XEN_EFI)) { + if ((of_get_flat_dt_subnode_by_name(node, "uefi") > 0) && + !efi_runtime_disabled()) + set_bit(EFI_RUNTIME_SERVICES, &efi.flags); + } + + return 0; +} + +/* + * see Documentation/devicetree/bindings/arm/xen.txt for the + * documentation of the Xen Device Tree format. + */ +void __init xen_early_init(void) +{ + of_scan_flat_dt(fdt_find_hyper_node, NULL); + if (!hyper_node.found) { + pr_debug("No Xen support\n"); + return; + } + + if (hyper_node.version == NULL) { + pr_debug("Xen version not found\n"); + return; + } + + pr_info("Xen %s support found\n", hyper_node.version); + + xen_domain_type = XEN_HVM_DOMAIN; + + xen_setup_features(); + + if (xen_feature(XENFEAT_dom0)) + xen_start_flags |= SIF_INITDOMAIN|SIF_PRIVILEGED; + + if (!console_set_on_cmdline && !xen_initial_domain()) + add_preferred_console("hvc", 0, NULL); +} + +static void __init xen_acpi_guest_init(void) +{ +#ifdef CONFIG_ACPI + struct xen_hvm_param a; + int interrupt, trigger, polarity; + + a.domid = DOMID_SELF; + a.index = HVM_PARAM_CALLBACK_IRQ; + + if (HYPERVISOR_hvm_op(HVMOP_get_param, &a) + || (a.value >> 56) != HVM_PARAM_CALLBACK_TYPE_PPI) { + xen_events_irq = 0; + return; + } + + interrupt = a.value & 0xff; + trigger = ((a.value >> 8) & 0x1) ? ACPI_EDGE_SENSITIVE + : ACPI_LEVEL_SENSITIVE; + polarity = ((a.value >> 8) & 0x2) ? ACPI_ACTIVE_LOW + : ACPI_ACTIVE_HIGH; + xen_events_irq = acpi_register_gsi(NULL, interrupt, trigger, polarity); +#endif +} + +static void __init xen_dt_guest_init(void) +{ + struct device_node *xen_node; + + xen_node = of_find_compatible_node(NULL, NULL, "xen,xen"); + if (!xen_node) { + pr_err("Xen support was detected before, but it has disappeared\n"); + return; + } + + xen_events_irq = irq_of_parse_and_map(xen_node, 0); +} + +static int __init xen_guest_init(void) +{ + struct xen_add_to_physmap xatp; + struct shared_info *shared_info_page = NULL; + int cpu; + + if (!xen_domain()) + return 0; + + if (!acpi_disabled) + xen_acpi_guest_init(); + else + xen_dt_guest_init(); + + if (!xen_events_irq) { + pr_err("Xen event channel interrupt not found\n"); + return -ENODEV; + } + + /* + * The fdt parsing codes have set EFI_RUNTIME_SERVICES if Xen EFI + * parameters are found. Force enable runtime services. + */ + if (efi_enabled(EFI_RUNTIME_SERVICES)) + xen_efi_runtime_setup(); + + shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL); + + if (!shared_info_page) { + pr_err("not enough memory\n"); + return -ENOMEM; + } + xatp.domid = DOMID_SELF; + xatp.idx = 0; + xatp.space = XENMAPSPACE_shared_info; + xatp.gpfn = virt_to_gfn(shared_info_page); + if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp)) + BUG(); + + HYPERVISOR_shared_info = (struct shared_info *)shared_info_page; + + /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info + * page, we use it in the event channel upcall and in some pvclock + * related functions. + * The shared info contains exactly 1 CPU (the boot CPU). The guest + * is required to use VCPUOP_register_vcpu_info to place vcpu info + * for secondary CPUs as they are brought up. + * For uniformity we use VCPUOP_register_vcpu_info even on cpu0. + */ + xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info), + 1 << fls(sizeof(struct vcpu_info) - 1)); + if (xen_vcpu_info == NULL) + return -ENOMEM; + + /* Direct vCPU id mapping for ARM guests. */ + for_each_possible_cpu(cpu) + per_cpu(xen_vcpu_id, cpu) = cpu; + + xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames(); + if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn, + &xen_auto_xlat_grant_frames.vaddr, + xen_auto_xlat_grant_frames.count)) { + free_percpu(xen_vcpu_info); + return -ENOMEM; + } + gnttab_init(); + + /* + * Making sure board specific code will not set up ops for + * cpu idle and cpu freq. + */ + disable_cpuidle(); + disable_cpufreq(); + + xen_init_IRQ(); + + if (request_percpu_irq(xen_events_irq, xen_arm_callback, + "events", &xen_vcpu)) { + pr_err("Error request IRQ %d\n", xen_events_irq); + return -EINVAL; + } + + if (xen_initial_domain()) + pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier); + + return cpuhp_setup_state(CPUHP_AP_ARM_XEN_STARTING, + "arm/xen:starting", xen_starting_cpu, + xen_dying_cpu); +} +early_initcall(xen_guest_init); + +static int xen_starting_runstate_cpu(unsigned int cpu) +{ + xen_setup_runstate_info(cpu); + return 0; +} + +static int __init xen_late_init(void) +{ + if (!xen_domain()) + return -ENODEV; + + pm_power_off = xen_power_off; + arm_pm_restart = xen_restart; + if (!xen_initial_domain()) { + struct timespec64 ts; + xen_read_wallclock(&ts); + do_settimeofday64(&ts); + } + + if (xen_kernel_unmapped_at_usr()) + return 0; + + xen_time_setup_guest(); + + return cpuhp_setup_state(CPUHP_AP_ARM_XEN_RUNSTATE_STARTING, + "arm/xen_runstate:starting", + xen_starting_runstate_cpu, NULL); +} +late_initcall(xen_late_init); + + +/* empty stubs */ +void xen_arch_pre_suspend(void) { } +void xen_arch_post_suspend(int suspend_cancelled) { } +void xen_timer_resume(void) { } +void xen_arch_resume(void) { } +void xen_arch_suspend(void) { } + + +/* In the hypercall.S file. */ +EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version); +EXPORT_SYMBOL_GPL(HYPERVISOR_console_io); +EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op); +EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op_raw); +EXPORT_SYMBOL_GPL(HYPERVISOR_multicall); +EXPORT_SYMBOL_GPL(HYPERVISOR_vm_assist); +EXPORT_SYMBOL_GPL(HYPERVISOR_dm_op); +EXPORT_SYMBOL_GPL(privcmd_call); |