xref: /openbmc/linux/arch/arm/xen/enlighten.c (revision a8da474e)
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/vcpu.h>
6 #include <xen/interface/xen.h>
7 #include <xen/interface/memory.h>
8 #include <xen/interface/hvm/params.h>
9 #include <xen/features.h>
10 #include <xen/platform_pci.h>
11 #include <xen/xenbus.h>
12 #include <xen/page.h>
13 #include <xen/interface/sched.h>
14 #include <xen/xen-ops.h>
15 #include <asm/xen/hypervisor.h>
16 #include <asm/xen/hypercall.h>
17 #include <asm/system_misc.h>
18 #include <linux/interrupt.h>
19 #include <linux/irqreturn.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_irq.h>
23 #include <linux/of_address.h>
24 #include <linux/cpuidle.h>
25 #include <linux/cpufreq.h>
26 #include <linux/cpu.h>
27 #include <linux/console.h>
28 
29 #include <linux/mm.h>
30 
31 struct start_info _xen_start_info;
32 struct start_info *xen_start_info = &_xen_start_info;
33 EXPORT_SYMBOL(xen_start_info);
34 
35 enum xen_domain_type xen_domain_type = XEN_NATIVE;
36 EXPORT_SYMBOL(xen_domain_type);
37 
38 struct shared_info xen_dummy_shared_info;
39 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
40 
41 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
42 static struct vcpu_info __percpu *xen_vcpu_info;
43 
44 /* These are unused until we support booting "pre-ballooned" */
45 unsigned long xen_released_pages;
46 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
47 
48 static __read_mostly unsigned int xen_events_irq;
49 
50 static __initdata struct device_node *xen_node;
51 
52 int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
53 			       unsigned long addr,
54 			       xen_pfn_t *gfn, int nr,
55 			       int *err_ptr, pgprot_t prot,
56 			       unsigned domid,
57 			       struct page **pages)
58 {
59 	return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr,
60 					 prot, domid, pages);
61 }
62 EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array);
63 
64 /* Not used by XENFEAT_auto_translated guests. */
65 int xen_remap_domain_gfn_range(struct vm_area_struct *vma,
66                               unsigned long addr,
67                               xen_pfn_t gfn, int nr,
68                               pgprot_t prot, unsigned domid,
69                               struct page **pages)
70 {
71 	return -ENOSYS;
72 }
73 EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range);
74 
75 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
76 			       int nr, struct page **pages)
77 {
78 	return xen_xlate_unmap_gfn_range(vma, nr, pages);
79 }
80 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);
81 
82 static void xen_percpu_init(void)
83 {
84 	struct vcpu_register_vcpu_info info;
85 	struct vcpu_info *vcpup;
86 	int err;
87 	int cpu = get_cpu();
88 
89 	/*
90 	 * VCPUOP_register_vcpu_info cannot be called twice for the same
91 	 * vcpu, so if vcpu_info is already registered, just get out. This
92 	 * can happen with cpu-hotplug.
93 	 */
94 	if (per_cpu(xen_vcpu, cpu) != NULL)
95 		goto after_register_vcpu_info;
96 
97 	pr_info("Xen: initializing cpu%d\n", cpu);
98 	vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
99 
100 	info.mfn = virt_to_gfn(vcpup);
101 	info.offset = xen_offset_in_page(vcpup);
102 
103 	err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, cpu, &info);
104 	BUG_ON(err);
105 	per_cpu(xen_vcpu, cpu) = vcpup;
106 
107 after_register_vcpu_info:
108 	enable_percpu_irq(xen_events_irq, 0);
109 	put_cpu();
110 }
111 
112 static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
113 {
114 	struct sched_shutdown r = { .reason = SHUTDOWN_reboot };
115 	int rc;
116 	rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
117 	BUG_ON(rc);
118 }
119 
120 static void xen_power_off(void)
121 {
122 	struct sched_shutdown r = { .reason = SHUTDOWN_poweroff };
123 	int rc;
124 	rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
125 	BUG_ON(rc);
126 }
127 
128 static int xen_cpu_notification(struct notifier_block *self,
129 				unsigned long action,
130 				void *hcpu)
131 {
132 	switch (action) {
133 	case CPU_STARTING:
134 		xen_percpu_init();
135 		break;
136 	case CPU_DYING:
137 		disable_percpu_irq(xen_events_irq);
138 		break;
139 	default:
140 		break;
141 	}
142 
143 	return NOTIFY_OK;
144 }
145 
146 static struct notifier_block xen_cpu_notifier = {
147 	.notifier_call = xen_cpu_notification,
148 };
149 
150 static irqreturn_t xen_arm_callback(int irq, void *arg)
151 {
152 	xen_hvm_evtchn_do_upcall();
153 	return IRQ_HANDLED;
154 }
155 
156 /*
157  * see Documentation/devicetree/bindings/arm/xen.txt for the
158  * documentation of the Xen Device Tree format.
159  */
160 #define GRANT_TABLE_PHYSADDR 0
161 void __init xen_early_init(void)
162 {
163 	int len;
164 	const char *s = NULL;
165 	const char *version = NULL;
166 	const char *xen_prefix = "xen,xen-";
167 
168 	xen_node = of_find_compatible_node(NULL, NULL, "xen,xen");
169 	if (!xen_node) {
170 		pr_debug("No Xen support\n");
171 		return;
172 	}
173 	s = of_get_property(xen_node, "compatible", &len);
174 	if (strlen(xen_prefix) + 3  < len &&
175 			!strncmp(xen_prefix, s, strlen(xen_prefix)))
176 		version = s + strlen(xen_prefix);
177 	if (version == NULL) {
178 		pr_debug("Xen version not found\n");
179 		return;
180 	}
181 
182 	pr_info("Xen %s support found\n", version);
183 
184 	xen_domain_type = XEN_HVM_DOMAIN;
185 
186 	xen_setup_features();
187 
188 	if (xen_feature(XENFEAT_dom0))
189 		xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
190 	else
191 		xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
192 
193 	if (!console_set_on_cmdline && !xen_initial_domain())
194 		add_preferred_console("hvc", 0, NULL);
195 }
196 
197 static int __init xen_guest_init(void)
198 {
199 	struct xen_add_to_physmap xatp;
200 	struct shared_info *shared_info_page = NULL;
201 	struct resource res;
202 	phys_addr_t grant_frames;
203 
204 	if (!xen_domain())
205 		return 0;
206 
207 	if (of_address_to_resource(xen_node, GRANT_TABLE_PHYSADDR, &res)) {
208 		pr_err("Xen grant table base address not found\n");
209 		return -ENODEV;
210 	}
211 	grant_frames = res.start;
212 
213 	xen_events_irq = irq_of_parse_and_map(xen_node, 0);
214 	if (!xen_events_irq) {
215 		pr_err("Xen event channel interrupt not found\n");
216 		return -ENODEV;
217 	}
218 
219 	shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL);
220 
221 	if (!shared_info_page) {
222 		pr_err("not enough memory\n");
223 		return -ENOMEM;
224 	}
225 	xatp.domid = DOMID_SELF;
226 	xatp.idx = 0;
227 	xatp.space = XENMAPSPACE_shared_info;
228 	xatp.gpfn = virt_to_gfn(shared_info_page);
229 	if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
230 		BUG();
231 
232 	HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
233 
234 	/* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
235 	 * page, we use it in the event channel upcall and in some pvclock
236 	 * related functions.
237 	 * The shared info contains exactly 1 CPU (the boot CPU). The guest
238 	 * is required to use VCPUOP_register_vcpu_info to place vcpu info
239 	 * for secondary CPUs as they are brought up.
240 	 * For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
241 	 */
242 	xen_vcpu_info = __alloc_percpu(sizeof(struct vcpu_info),
243 			                       sizeof(struct vcpu_info));
244 	if (xen_vcpu_info == NULL)
245 		return -ENOMEM;
246 
247 	if (gnttab_setup_auto_xlat_frames(grant_frames)) {
248 		free_percpu(xen_vcpu_info);
249 		return -ENOMEM;
250 	}
251 	gnttab_init();
252 	if (!xen_initial_domain())
253 		xenbus_probe(NULL);
254 
255 	/*
256 	 * Making sure board specific code will not set up ops for
257 	 * cpu idle and cpu freq.
258 	 */
259 	disable_cpuidle();
260 	disable_cpufreq();
261 
262 	xen_init_IRQ();
263 
264 	if (request_percpu_irq(xen_events_irq, xen_arm_callback,
265 			       "events", &xen_vcpu)) {
266 		pr_err("Error request IRQ %d\n", xen_events_irq);
267 		return -EINVAL;
268 	}
269 
270 	xen_percpu_init();
271 
272 	register_cpu_notifier(&xen_cpu_notifier);
273 
274 	return 0;
275 }
276 early_initcall(xen_guest_init);
277 
278 static int __init xen_pm_init(void)
279 {
280 	if (!xen_domain())
281 		return -ENODEV;
282 
283 	pm_power_off = xen_power_off;
284 	arm_pm_restart = xen_restart;
285 
286 	return 0;
287 }
288 late_initcall(xen_pm_init);
289 
290 
291 /* empty stubs */
292 void xen_arch_pre_suspend(void) { }
293 void xen_arch_post_suspend(int suspend_cancelled) { }
294 void xen_timer_resume(void) { }
295 void xen_arch_resume(void) { }
296 void xen_arch_suspend(void) { }
297 
298 
299 /* In the hypercall.S file. */
300 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
301 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
302 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
303 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
304 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
305 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
306 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
307 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
308 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
309 EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
310 EXPORT_SYMBOL_GPL(HYPERVISOR_multicall);
311 EXPORT_SYMBOL_GPL(privcmd_call);
312