xref: /openbmc/linux/arch/arm/xen/enlighten.c (revision 05bcf503)
1 #include <xen/xen.h>
2 #include <xen/events.h>
3 #include <xen/grant_table.h>
4 #include <xen/hvm.h>
5 #include <xen/interface/xen.h>
6 #include <xen/interface/memory.h>
7 #include <xen/interface/hvm/params.h>
8 #include <xen/features.h>
9 #include <xen/platform_pci.h>
10 #include <xen/xenbus.h>
11 #include <asm/xen/hypervisor.h>
12 #include <asm/xen/hypercall.h>
13 #include <linux/interrupt.h>
14 #include <linux/irqreturn.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_address.h>
19 
20 struct start_info _xen_start_info;
21 struct start_info *xen_start_info = &_xen_start_info;
22 EXPORT_SYMBOL_GPL(xen_start_info);
23 
24 enum xen_domain_type xen_domain_type = XEN_NATIVE;
25 EXPORT_SYMBOL_GPL(xen_domain_type);
26 
27 struct shared_info xen_dummy_shared_info;
28 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
29 
30 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
31 
32 /* TODO: to be removed */
33 __read_mostly int xen_have_vector_callback;
34 EXPORT_SYMBOL_GPL(xen_have_vector_callback);
35 
36 int xen_platform_pci_unplug = XEN_UNPLUG_ALL;
37 EXPORT_SYMBOL_GPL(xen_platform_pci_unplug);
38 
39 static __read_mostly int xen_events_irq = -1;
40 
41 int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
42 			       unsigned long addr,
43 			       unsigned long mfn, int nr,
44 			       pgprot_t prot, unsigned domid)
45 {
46 	return -ENOSYS;
47 }
48 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
49 
50 /*
51  * see Documentation/devicetree/bindings/arm/xen.txt for the
52  * documentation of the Xen Device Tree format.
53  */
54 #define GRANT_TABLE_PHYSADDR 0
55 static int __init xen_guest_init(void)
56 {
57 	struct xen_add_to_physmap xatp;
58 	static struct shared_info *shared_info_page = 0;
59 	struct device_node *node;
60 	int len;
61 	const char *s = NULL;
62 	const char *version = NULL;
63 	const char *xen_prefix = "xen,xen-";
64 	struct resource res;
65 
66 	node = of_find_compatible_node(NULL, NULL, "xen,xen");
67 	if (!node) {
68 		pr_debug("No Xen support\n");
69 		return 0;
70 	}
71 	s = of_get_property(node, "compatible", &len);
72 	if (strlen(xen_prefix) + 3  < len &&
73 			!strncmp(xen_prefix, s, strlen(xen_prefix)))
74 		version = s + strlen(xen_prefix);
75 	if (version == NULL) {
76 		pr_debug("Xen version not found\n");
77 		return 0;
78 	}
79 	if (of_address_to_resource(node, GRANT_TABLE_PHYSADDR, &res))
80 		return 0;
81 	xen_hvm_resume_frames = res.start >> PAGE_SHIFT;
82 	xen_events_irq = irq_of_parse_and_map(node, 0);
83 	pr_info("Xen %s support found, events_irq=%d gnttab_frame_pfn=%lx\n",
84 			version, xen_events_irq, xen_hvm_resume_frames);
85 	xen_domain_type = XEN_HVM_DOMAIN;
86 
87 	xen_setup_features();
88 	if (xen_feature(XENFEAT_dom0))
89 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
90 	else
91 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
92 
93 	if (!shared_info_page)
94 		shared_info_page = (struct shared_info *)
95 			get_zeroed_page(GFP_KERNEL);
96 	if (!shared_info_page) {
97 		pr_err("not enough memory\n");
98 		return -ENOMEM;
99 	}
100 	xatp.domid = DOMID_SELF;
101 	xatp.idx = 0;
102 	xatp.space = XENMAPSPACE_shared_info;
103 	xatp.gpfn = __pa(shared_info_page) >> PAGE_SHIFT;
104 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
105 		BUG();
106 
107 	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
108 
109 	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
110 	 * page, we use it in the event channel upcall and in some pvclock
111 	 * related functions. We don't need the vcpu_info placement
112 	 * optimizations because we don't use any pv_mmu or pv_irq op on
113 	 * HVM.
114 	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
115 	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
116 	 * for secondary CPUs as they are brought up. */
117 	per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
118 
119 	gnttab_init();
120 	if (!xen_initial_domain())
121 		xenbus_probe(NULL);
122 
123 	return 0;
124 }
125 core_initcall(xen_guest_init);
126 
127 static irqreturn_t xen_arm_callback(int irq, void *arg)
128 {
129 	xen_hvm_evtchn_do_upcall();
130 	return IRQ_HANDLED;
131 }
132 
133 static int __init xen_init_events(void)
134 {
135 	if (!xen_domain() || xen_events_irq < 0)
136 		return -ENODEV;
137 
138 	xen_init_IRQ();
139 
140 	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
141 			"events", xen_vcpu)) {
142 		pr_err("Error requesting IRQ %d\n", xen_events_irq);
143 		return -EINVAL;
144 	}
145 
146 	enable_percpu_irq(xen_events_irq, 0);
147 
148 	return 0;
149 }
150 postcore_initcall(xen_init_events);
151 
152 /* XXX: only until balloon is properly working */
153 int alloc_xenballooned_pages(int nr_pages, struct page **pages, bool highmem)
154 {
155 	*pages = alloc_pages(highmem ? GFP_HIGHUSER : GFP_KERNEL,
156 			get_order(nr_pages));
157 	if (*pages == NULL)
158 		return -ENOMEM;
159 	return 0;
160 }
161 EXPORT_SYMBOL_GPL(alloc_xenballooned_pages);
162 
163 void free_xenballooned_pages(int nr_pages, struct page **pages)
164 {
165 	kfree(*pages);
166 	*pages = NULL;
167 }
168 EXPORT_SYMBOL_GPL(free_xenballooned_pages);
169 
170 /* In the hypervisor.S file. */
171 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
172 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
173 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
174 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
175 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
176 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
177 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
178 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
179 EXPORT_SYMBOL_GPL(privcmd_call);
180