[linux-2.6-block.git] / arch / arm / xen / enlighten.c

// 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;

	if (!xen_kernel_unmapped_at_usr())
		xen_setup_runstate_info(cpu);

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(struct vcpu_info);
	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();
	if (!xen_initial_domain())
		xenbus_probe();

	/*
	 * 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_kernel_unmapped_at_usr())
		xen_time_setup_guest();

	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 __init xen_pm_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);
	}

	return 0;
}
late_initcall(xen_pm_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);
Commit	Line	Data
457c8996	1	// SPDX-License-Identifier: GPL-2.0-only
4c071ee5	2	#include <xen/xen.h>
0ec53ecf	3	#include <xen/events.h>
b3b52fd8 SS	4	#include <xen/grant_table.h>
b3b52fd8 SS	5	#include <xen/hvm.h>
9a9ab3cc	6	#include <xen/interface/vcpu.h>
4c071ee5 SS	7	#include <xen/interface/xen.h>
4c071ee5 SS	8	#include <xen/interface/memory.h>
b3b52fd8	9	#include <xen/interface/hvm/params.h>
ef61ee0d	10	#include <xen/features.h>
4c071ee5	11	#include <xen/platform_pci.h>
b3b52fd8	12	#include <xen/xenbus.h>
c61ba729	13	#include <xen/page.h>
6abb749e	14	#include <xen/interface/sched.h>
f832da06	15	#include <xen/xen-ops.h>
4c071ee5 SS	16	#include <asm/xen/hypervisor.h>
4c071ee5 SS	17	#include <asm/xen/hypercall.h>
6abb749e	18	#include <asm/system_misc.h>
0cac5c30	19	#include <asm/efi.h>
0ec53ecf SS	20	#include <linux/interrupt.h>
0ec53ecf SS	21	#include <linux/irqreturn.h>
4c071ee5	22	#include <linux/module.h>
2e01f166	23	#include <linux/of.h>
9b08aaa3	24	#include <linux/of_fdt.h>
2e01f166 SS	25	#include <linux/of_irq.h>
2e01f166 SS	26	#include <linux/of_address.h>
e1a9c16b JG	27	#include <linux/cpuidle.h>
e1a9c16b JG	28	#include <linux/cpufreq.h>
8b271d57	29	#include <linux/cpu.h>
f1dddd11	30	#include <linux/console.h>
7d5f6f81 SS	31	#include <linux/pvclock_gtod.h>
7d5f6f81 SS	32	#include <linux/time64.h>
e709fba1	33	#include <linux/timekeeping.h>
7d5f6f81	34	#include <linux/timekeeper_internal.h>
d22cbe65	35	#include <linux/acpi.h>
4c071ee5	36
f832da06 IC	37	#include <linux/mm.h>
f832da06 IC	38
74f4c438	39	static struct start_info _xen_start_info;
4c071ee5	40	struct start_info *xen_start_info = &_xen_start_info;
35c8ab4c	41	EXPORT_SYMBOL(xen_start_info);
4c071ee5 SS	42
4c071ee5 SS	43	enum xen_domain_type xen_domain_type = XEN_NATIVE;
35c8ab4c	44	EXPORT_SYMBOL(xen_domain_type);
4c071ee5 SS	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);
9a9ab3cc	50	static struct vcpu_info __percpu *xen_vcpu_info;
4c071ee5	51
88e957d6	52	/* Linux <-> Xen vCPU id mapping */
55467dea	53	DEFINE_PER_CPU(uint32_t, xen_vcpu_id);
88e957d6 VK	54	EXPORT_PER_CPU_SYMBOL(xen_vcpu_id);
88e957d6 VK	55
c61ba729 IC	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
81e863c3	60	static __read_mostly unsigned int xen_events_irq;
0ec53ecf	61
1fe83888 RPM	62	uint32_t xen_start_flags;
	63	EXPORT_SYMBOL(xen_start_flags);
	64
a13d7201	65	int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
f832da06 IC	66	int nr, struct page **pages)
f832da06 IC	67	{
628c28ee	68	return xen_xlate_unmap_gfn_range(vma, nr, pages);
f832da06	69	}
a13d7201	70	EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);
f832da06	71
e709fba1 SS	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
7d5f6f81 SS	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
4761adb6	136	static int xen_starting_cpu(unsigned int cpu)
9a9ab3cc SS	137	{
	138	struct vcpu_register_vcpu_info info;
	139	struct vcpu_info *vcpup;
	140	int err;
	141
cb9644bf SS	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
9a9ab3cc SS	150	pr_info("Xen: initializing cpu%d\n", cpu);
	151	vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
	152
5a067711	153	info.mfn = percpu_to_gfn(vcpup);
250c9af3	154	info.offset = xen_offset_in_page(vcpup);
9a9ab3cc	155
ad5475f9 VK	156	err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, xen_vcpu_nr(cpu),
ad5475f9 VK	157	&info);
d7266d78 SS	158	BUG_ON(err);
	159	per_cpu(xen_vcpu, cpu) = vcpup;
	160
f88af722 SS	161	if (!xen_kernel_unmapped_at_usr())
f88af722 SS	162	xen_setup_runstate_info(cpu);
34e38523	163
cb9644bf	164	after_register_vcpu_info:
3cc8e40e	165	enable_percpu_irq(xen_events_irq, 0);
4761adb6 RC	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;
9a9ab3cc SS	173	}
9a9ab3cc SS	174
fa12a870	175	void xen_reboot(int reason)
6abb749e	176	{
fa12a870	177	struct sched_shutdown r = { .reason = reason };
6abb749e	178	int rc;
fa12a870	179
6abb749e	180	rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
a91c7775	181	BUG_ON(rc);
6abb749e SS	182	}
6abb749e SS	183
fa12a870 JG	184	static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
	185	{
	186	xen_reboot(SHUTDOWN_reboot);
	187	}
	188
	189
6abb749e SS	190	static void xen_power_off(void)
6abb749e SS	191	{
fa12a870	192	xen_reboot(SHUTDOWN_poweroff);
6abb749e SS	193	}
6abb749e SS	194
8b271d57 JG	195	static irqreturn_t xen_arm_callback(int irq, void *arg)
	196	{
	197	xen_hvm_evtchn_do_upcall();
	198	return IRQ_HANDLED;
	199	}
	200
9b08aaa3 SZ	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
0cac5c30 SZ	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
9b08aaa3 SZ	238	return 0;
	239	}
	240
2e01f166 SS	241	/*
	242	* see Documentation/devicetree/bindings/arm/xen.txt for the
	243	* documentation of the Xen Device Tree format.
	244	*/
5882bfef	245	void __init xen_early_init(void)
2e01f166	246	{
9b08aaa3 SZ	247	of_scan_flat_dt(fdt_find_hyper_node, NULL);
9b08aaa3 SZ	248	if (!hyper_node.found) {
2e01f166	249	pr_debug("No Xen support\n");
5882bfef	250	return;
2e01f166	251	}
9b08aaa3 SZ	252
9b08aaa3 SZ	253	if (hyper_node.version == NULL) {
2e01f166	254	pr_debug("Xen version not found\n");
5882bfef	255	return;
81e863c3 JG	256	}
81e863c3 JG	257
9b08aaa3	258	pr_info("Xen %s support found\n", hyper_node.version);
8b271d57	259
2e01f166 SS	260	xen_domain_type = XEN_HVM_DOMAIN;
2e01f166 SS	261
ef61ee0d	262	xen_setup_features();
5ebc77de	263
ef61ee0d	264	if (xen_feature(XENFEAT_dom0))
1fe83888	265	xen_start_flags \|= SIF_INITDOMAIN\|SIF_PRIVILEGED;
f1dddd11 AB	266
	267	if (!console_set_on_cmdline && !xen_initial_domain())
	268	add_preferred_console("hvc", 0, NULL);
5882bfef SS	269	}
5882bfef SS	270
d22cbe65 SZ	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	{
9b08aaa3 SZ	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
d22cbe65 SZ	305	xen_events_irq = irq_of_parse_and_map(xen_node, 0);
	306	}
	307
5882bfef SS	308	static int __init xen_guest_init(void)
	309	{
	310	struct xen_add_to_physmap xatp;
	311	struct shared_info *shared_info_page = NULL;
de75abbe	312	int cpu;
5882bfef SS	313
	314	if (!xen_domain())
	315	return 0;
	316
d22cbe65 SZ	317	if (!acpi_disabled)
	318	xen_acpi_guest_init();
	319	else
	320	xen_dt_guest_init();
	321
5882bfef SS	322	if (!xen_events_irq) {
	323	pr_err("Xen event channel interrupt not found\n");
	324	return -ENODEV;
	325	}
	326
0cac5c30 SZ	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
5882bfef	334	shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL);
ef61ee0d	335
2e01f166 SS	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;
250c9af3	343	xatp.gpfn = virt_to_gfn(shared_info_page);
2e01f166 SS	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
9a9ab3cc	351	* related functions.
2e01f166 SS	352	* The shared info contains exactly 1 CPU (the boot CPU). The guest
2e01f166 SS	353	* is required to use VCPUOP_register_vcpu_info to place vcpu info
9a9ab3cc SS	354	* for secondary CPUs as they are brought up.
	355	* For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
	356	*/
24d5373d	357	xen_vcpu_info = alloc_percpu(struct vcpu_info);
9a9ab3cc SS	358	if (xen_vcpu_info == NULL)
9a9ab3cc SS	359	return -ENOMEM;
b3b52fd8	360
88e957d6	361	/* Direct vCPU id mapping for ARM guests. */
de75abbe VK	362	for_each_possible_cpu(cpu)
de75abbe VK	363	per_cpu(xen_vcpu_id, cpu) = cpu;
88e957d6	364
3cf4095d SZ	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)) {
efaf30a3 KRW	369	free_percpu(xen_vcpu_info);
	370	return -ENOMEM;
	371	}
b3b52fd8 SS	372	gnttab_init();
b3b52fd8 SS	373	if (!xen_initial_domain())
3499ba81	374	xenbus_probe();
b3b52fd8	375
e1a9c16b JG	376	/*
	377	* Making sure board specific code will not set up ops for
	378	* cpu idle and cpu freq.
	379	*/
	380	disable_cpuidle();
	381	disable_cpufreq();
	382
8b271d57 JG	383	xen_init_IRQ();
	384
	385	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
	386	"events", &xen_vcpu)) {
	387	pr_err("Error request IRQ %d\n", xen_events_irq);
	388	return -EINVAL;
	389	}
	390
f88af722 SS	391	if (!xen_kernel_unmapped_at_usr())
f88af722 SS	392	xen_time_setup_guest();
ecb23dc6	393
7d5f6f81 SS	394	if (xen_initial_domain())
7d5f6f81 SS	395	pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier);
34e38523	396
4761adb6	397	return cpuhp_setup_state(CPUHP_AP_ARM_XEN_STARTING,
73c1b41e	398	"arm/xen:starting", xen_starting_cpu,
4761adb6	399	xen_dying_cpu);
1aa3d8d9	400	}
8b271d57	401	early_initcall(xen_guest_init);
1aa3d8d9 SS	402
	403	static int __init xen_pm_init(void)
	404	{
9dd4b294 RH	405	if (!xen_domain())
	406	return -ENODEV;
	407
6abb749e SS	408	pm_power_off = xen_power_off;
6abb749e SS	409	arm_pm_restart = xen_restart;
e709fba1 SS	410	if (!xen_initial_domain()) {
	411	struct timespec64 ts;
	412	xen_read_wallclock(&ts);
	413	do_settimeofday64(&ts);
	414	}
6abb749e	415
2e01f166 SS	416	return 0;
2e01f166 SS	417	}
9dd4b294	418	late_initcall(xen_pm_init);
0ec53ecf	419
79390289 SS	420
	421	/* empty stubs */
	422	void xen_arch_pre_suspend(void) { }
	423	void xen_arch_post_suspend(int suspend_cancelled) { }
	424	void xen_timer_resume(void) { }
	425	void xen_arch_resume(void) { }
ffb7dbed	426	void xen_arch_suspend(void) { }
79390289 SS	427
79390289 SS	428
d5f985c8	429	/* In the hypercall.S file. */
911dec0d KRW	430	EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
911dec0d KRW	431	EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
ab277bbf SS	432	EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
	433	EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
	434	EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
	435	EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
	436	EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
	437	EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
ea0af613	438	EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
176455e9	439	EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
ade77a2d	440	EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op_raw);
9f1d3414	441	EXPORT_SYMBOL_GPL(HYPERVISOR_multicall);
4b5ae015	442	EXPORT_SYMBOL_GPL(HYPERVISOR_vm_assist);
ab520be8	443	EXPORT_SYMBOL_GPL(HYPERVISOR_dm_op);
911dec0d	444	EXPORT_SYMBOL_GPL(privcmd_call);