1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * EFI support for Xen.
4  *
5  * Copyright (C) 1999 VA Linux Systems
6  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
7  * Copyright (C) 1999-2002 Hewlett-Packard Co.
8  *	David Mosberger-Tang <davidm@hpl.hp.com>
9  *	Stephane Eranian <eranian@hpl.hp.com>
10  * Copyright (C) 2005-2008 Intel Co.
11  *	Fenghua Yu <fenghua.yu@intel.com>
12  *	Bibo Mao <bibo.mao@intel.com>
13  *	Chandramouli Narayanan <mouli@linux.intel.com>
14  *	Huang Ying <ying.huang@intel.com>
15  * Copyright (C) 2011 Novell Co.
16  *	Jan Beulich <JBeulich@suse.com>
17  * Copyright (C) 2011-2012 Oracle Co.
18  *	Liang Tang <liang.tang@oracle.com>
19  * Copyright (c) 2014 Oracle Co., Daniel Kiper
20  */
21 
22 #include <linux/bug.h>
23 #include <linux/efi.h>
24 #include <linux/init.h>
25 #include <linux/string.h>
26 
27 #include <xen/interface/xen.h>
28 #include <xen/interface/platform.h>
29 #include <xen/xen.h>
30 #include <xen/xen-ops.h>
31 
32 #include <asm/page.h>
33 
34 #include <asm/xen/hypercall.h>
35 
36 #define INIT_EFI_OP(name) \
37 	{.cmd = XENPF_efi_runtime_call, \
38 	 .u.efi_runtime_call.function = XEN_EFI_##name, \
39 	 .u.efi_runtime_call.misc = 0}
40 
41 #define efi_data(op)	(op.u.efi_runtime_call)
42 
xen_efi_get_time(efi_time_t * tm,efi_time_cap_t * tc)43 static efi_status_t xen_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
44 {
45 	struct xen_platform_op op = INIT_EFI_OP(get_time);
46 
47 	if (HYPERVISOR_platform_op(&op) < 0)
48 		return EFI_UNSUPPORTED;
49 
50 	if (tm) {
51 		BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.get_time.time));
52 		memcpy(tm, &efi_data(op).u.get_time.time, sizeof(*tm));
53 	}
54 
55 	if (tc) {
56 		tc->resolution = efi_data(op).u.get_time.resolution;
57 		tc->accuracy = efi_data(op).u.get_time.accuracy;
58 		tc->sets_to_zero = !!(efi_data(op).misc &
59 				      XEN_EFI_GET_TIME_SET_CLEARS_NS);
60 	}
61 
62 	return efi_data(op).status;
63 }
64 
xen_efi_set_time(efi_time_t * tm)65 static efi_status_t xen_efi_set_time(efi_time_t *tm)
66 {
67 	struct xen_platform_op op = INIT_EFI_OP(set_time);
68 
69 	BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.set_time));
70 	memcpy(&efi_data(op).u.set_time, tm, sizeof(*tm));
71 
72 	if (HYPERVISOR_platform_op(&op) < 0)
73 		return EFI_UNSUPPORTED;
74 
75 	return efi_data(op).status;
76 }
77 
xen_efi_get_wakeup_time(efi_bool_t * enabled,efi_bool_t * pending,efi_time_t * tm)78 static efi_status_t xen_efi_get_wakeup_time(efi_bool_t *enabled,
79 					    efi_bool_t *pending,
80 					    efi_time_t *tm)
81 {
82 	struct xen_platform_op op = INIT_EFI_OP(get_wakeup_time);
83 
84 	if (HYPERVISOR_platform_op(&op) < 0)
85 		return EFI_UNSUPPORTED;
86 
87 	if (tm) {
88 		BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.get_wakeup_time));
89 		memcpy(tm, &efi_data(op).u.get_wakeup_time, sizeof(*tm));
90 	}
91 
92 	if (enabled)
93 		*enabled = !!(efi_data(op).misc & XEN_EFI_GET_WAKEUP_TIME_ENABLED);
94 
95 	if (pending)
96 		*pending = !!(efi_data(op).misc & XEN_EFI_GET_WAKEUP_TIME_PENDING);
97 
98 	return efi_data(op).status;
99 }
100 
xen_efi_set_wakeup_time(efi_bool_t enabled,efi_time_t * tm)101 static efi_status_t xen_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
102 {
103 	struct xen_platform_op op = INIT_EFI_OP(set_wakeup_time);
104 
105 	BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.set_wakeup_time));
106 	if (enabled)
107 		efi_data(op).misc = XEN_EFI_SET_WAKEUP_TIME_ENABLE;
108 	if (tm)
109 		memcpy(&efi_data(op).u.set_wakeup_time, tm, sizeof(*tm));
110 	else
111 		efi_data(op).misc |= XEN_EFI_SET_WAKEUP_TIME_ENABLE_ONLY;
112 
113 	if (HYPERVISOR_platform_op(&op) < 0)
114 		return EFI_UNSUPPORTED;
115 
116 	return efi_data(op).status;
117 }
118 
xen_efi_get_variable(efi_char16_t * name,efi_guid_t * vendor,u32 * attr,unsigned long * data_size,void * data)119 static efi_status_t xen_efi_get_variable(efi_char16_t *name, efi_guid_t *vendor,
120 					 u32 *attr, unsigned long *data_size,
121 					 void *data)
122 {
123 	struct xen_platform_op op = INIT_EFI_OP(get_variable);
124 
125 	set_xen_guest_handle(efi_data(op).u.get_variable.name, name);
126 	BUILD_BUG_ON(sizeof(*vendor) !=
127 		     sizeof(efi_data(op).u.get_variable.vendor_guid));
128 	memcpy(&efi_data(op).u.get_variable.vendor_guid, vendor, sizeof(*vendor));
129 	efi_data(op).u.get_variable.size = *data_size;
130 	set_xen_guest_handle(efi_data(op).u.get_variable.data, data);
131 
132 	if (HYPERVISOR_platform_op(&op) < 0)
133 		return EFI_UNSUPPORTED;
134 
135 	*data_size = efi_data(op).u.get_variable.size;
136 	if (attr)
137 		*attr = efi_data(op).misc;
138 
139 	return efi_data(op).status;
140 }
141 
xen_efi_get_next_variable(unsigned long * name_size,efi_char16_t * name,efi_guid_t * vendor)142 static efi_status_t xen_efi_get_next_variable(unsigned long *name_size,
143 					      efi_char16_t *name,
144 					      efi_guid_t *vendor)
145 {
146 	struct xen_platform_op op = INIT_EFI_OP(get_next_variable_name);
147 
148 	efi_data(op).u.get_next_variable_name.size = *name_size;
149 	set_xen_guest_handle(efi_data(op).u.get_next_variable_name.name, name);
150 	BUILD_BUG_ON(sizeof(*vendor) !=
151 		     sizeof(efi_data(op).u.get_next_variable_name.vendor_guid));
152 	memcpy(&efi_data(op).u.get_next_variable_name.vendor_guid, vendor,
153 	       sizeof(*vendor));
154 
155 	if (HYPERVISOR_platform_op(&op) < 0)
156 		return EFI_UNSUPPORTED;
157 
158 	*name_size = efi_data(op).u.get_next_variable_name.size;
159 	memcpy(vendor, &efi_data(op).u.get_next_variable_name.vendor_guid,
160 	       sizeof(*vendor));
161 
162 	return efi_data(op).status;
163 }
164 
xen_efi_set_variable(efi_char16_t * name,efi_guid_t * vendor,u32 attr,unsigned long data_size,void * data)165 static efi_status_t xen_efi_set_variable(efi_char16_t *name, efi_guid_t *vendor,
166 					 u32 attr, unsigned long data_size,
167 					 void *data)
168 {
169 	struct xen_platform_op op = INIT_EFI_OP(set_variable);
170 
171 	set_xen_guest_handle(efi_data(op).u.set_variable.name, name);
172 	efi_data(op).misc = attr;
173 	BUILD_BUG_ON(sizeof(*vendor) !=
174 		     sizeof(efi_data(op).u.set_variable.vendor_guid));
175 	memcpy(&efi_data(op).u.set_variable.vendor_guid, vendor, sizeof(*vendor));
176 	efi_data(op).u.set_variable.size = data_size;
177 	set_xen_guest_handle(efi_data(op).u.set_variable.data, data);
178 
179 	if (HYPERVISOR_platform_op(&op) < 0)
180 		return EFI_UNSUPPORTED;
181 
182 	return efi_data(op).status;
183 }
184 
xen_efi_query_variable_info(u32 attr,u64 * storage_space,u64 * remaining_space,u64 * max_variable_size)185 static efi_status_t xen_efi_query_variable_info(u32 attr, u64 *storage_space,
186 						u64 *remaining_space,
187 						u64 *max_variable_size)
188 {
189 	struct xen_platform_op op = INIT_EFI_OP(query_variable_info);
190 
191 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
192 		return EFI_UNSUPPORTED;
193 
194 	efi_data(op).u.query_variable_info.attr = attr;
195 
196 	if (HYPERVISOR_platform_op(&op) < 0)
197 		return EFI_UNSUPPORTED;
198 
199 	*storage_space = efi_data(op).u.query_variable_info.max_store_size;
200 	*remaining_space = efi_data(op).u.query_variable_info.remain_store_size;
201 	*max_variable_size = efi_data(op).u.query_variable_info.max_size;
202 
203 	return efi_data(op).status;
204 }
205 
xen_efi_get_next_high_mono_count(u32 * count)206 static efi_status_t xen_efi_get_next_high_mono_count(u32 *count)
207 {
208 	struct xen_platform_op op = INIT_EFI_OP(get_next_high_monotonic_count);
209 
210 	if (HYPERVISOR_platform_op(&op) < 0)
211 		return EFI_UNSUPPORTED;
212 
213 	*count = efi_data(op).misc;
214 
215 	return efi_data(op).status;
216 }
217 
xen_efi_update_capsule(efi_capsule_header_t ** capsules,unsigned long count,unsigned long sg_list)218 static efi_status_t xen_efi_update_capsule(efi_capsule_header_t **capsules,
219 				unsigned long count, unsigned long sg_list)
220 {
221 	struct xen_platform_op op = INIT_EFI_OP(update_capsule);
222 
223 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
224 		return EFI_UNSUPPORTED;
225 
226 	set_xen_guest_handle(efi_data(op).u.update_capsule.capsule_header_array,
227 			     capsules);
228 	efi_data(op).u.update_capsule.capsule_count = count;
229 	efi_data(op).u.update_capsule.sg_list = sg_list;
230 
231 	if (HYPERVISOR_platform_op(&op) < 0)
232 		return EFI_UNSUPPORTED;
233 
234 	return efi_data(op).status;
235 }
236 
xen_efi_query_capsule_caps(efi_capsule_header_t ** capsules,unsigned long count,u64 * max_size,int * reset_type)237 static efi_status_t xen_efi_query_capsule_caps(efi_capsule_header_t **capsules,
238 			unsigned long count, u64 *max_size, int *reset_type)
239 {
240 	struct xen_platform_op op = INIT_EFI_OP(query_capsule_capabilities);
241 
242 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
243 		return EFI_UNSUPPORTED;
244 
245 	set_xen_guest_handle(efi_data(op).u.query_capsule_capabilities.capsule_header_array,
246 					capsules);
247 	efi_data(op).u.query_capsule_capabilities.capsule_count = count;
248 
249 	if (HYPERVISOR_platform_op(&op) < 0)
250 		return EFI_UNSUPPORTED;
251 
252 	*max_size = efi_data(op).u.query_capsule_capabilities.max_capsule_size;
253 	*reset_type = efi_data(op).u.query_capsule_capabilities.reset_type;
254 
255 	return efi_data(op).status;
256 }
257 
xen_efi_reset_system(int reset_type,efi_status_t status,unsigned long data_size,efi_char16_t * data)258 static void xen_efi_reset_system(int reset_type, efi_status_t status,
259 				 unsigned long data_size, efi_char16_t *data)
260 {
261 	switch (reset_type) {
262 	case EFI_RESET_COLD:
263 	case EFI_RESET_WARM:
264 		xen_reboot(SHUTDOWN_reboot);
265 		break;
266 	case EFI_RESET_SHUTDOWN:
267 		xen_reboot(SHUTDOWN_poweroff);
268 		break;
269 	default:
270 		BUG();
271 	}
272 }
273 
274 /*
275  * Set XEN EFI runtime services function pointers. Other fields of struct efi,
276  * e.g. efi.systab, will be set like normal EFI.
277  */
xen_efi_runtime_setup(void)278 void __init xen_efi_runtime_setup(void)
279 {
280 	efi.get_time			= xen_efi_get_time;
281 	efi.set_time			= xen_efi_set_time;
282 	efi.get_wakeup_time		= xen_efi_get_wakeup_time;
283 	efi.set_wakeup_time		= xen_efi_set_wakeup_time;
284 	efi.get_variable		= xen_efi_get_variable;
285 	efi.get_next_variable		= xen_efi_get_next_variable;
286 	efi.set_variable		= xen_efi_set_variable;
287 	efi.set_variable_nonblocking	= xen_efi_set_variable;
288 	efi.query_variable_info		= xen_efi_query_variable_info;
289 	efi.query_variable_info_nonblocking = xen_efi_query_variable_info;
290 	efi.update_capsule		= xen_efi_update_capsule;
291 	efi.query_capsule_caps		= xen_efi_query_capsule_caps;
292 	efi.get_next_high_mono_count	= xen_efi_get_next_high_mono_count;
293 	efi.reset_system		= xen_efi_reset_system;
294 }
295