xref: /openbmc/linux/drivers/xen/efi.c (revision 2572f00d)
1 /*
2  * EFI support for Xen.
3  *
4  * Copyright (C) 1999 VA Linux Systems
5  * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
6  * Copyright (C) 1999-2002 Hewlett-Packard Co.
7  *	David Mosberger-Tang <davidm@hpl.hp.com>
8  *	Stephane Eranian <eranian@hpl.hp.com>
9  * Copyright (C) 2005-2008 Intel Co.
10  *	Fenghua Yu <fenghua.yu@intel.com>
11  *	Bibo Mao <bibo.mao@intel.com>
12  *	Chandramouli Narayanan <mouli@linux.intel.com>
13  *	Huang Ying <ying.huang@intel.com>
14  * Copyright (C) 2011 Novell Co.
15  *	Jan Beulich <JBeulich@suse.com>
16  * Copyright (C) 2011-2012 Oracle Co.
17  *	Liang Tang <liang.tang@oracle.com>
18  * Copyright (c) 2014 Oracle Co., Daniel Kiper
19  */
20 
21 #include <linux/bug.h>
22 #include <linux/efi.h>
23 #include <linux/init.h>
24 #include <linux/string.h>
25 
26 #include <xen/interface/xen.h>
27 #include <xen/interface/platform.h>
28 #include <xen/xen.h>
29 
30 #include <asm/page.h>
31 
32 #include <asm/xen/hypercall.h>
33 
34 #define INIT_EFI_OP(name) \
35 	{.cmd = XENPF_efi_runtime_call, \
36 	 .u.efi_runtime_call.function = XEN_EFI_##name, \
37 	 .u.efi_runtime_call.misc = 0}
38 
39 #define efi_data(op)	(op.u.efi_runtime_call)
40 
41 static efi_status_t xen_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
42 {
43 	struct xen_platform_op op = INIT_EFI_OP(get_time);
44 
45 	if (HYPERVISOR_dom0_op(&op) < 0)
46 		return EFI_UNSUPPORTED;
47 
48 	if (tm) {
49 		BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.get_time.time));
50 		memcpy(tm, &efi_data(op).u.get_time.time, sizeof(*tm));
51 	}
52 
53 	if (tc) {
54 		tc->resolution = efi_data(op).u.get_time.resolution;
55 		tc->accuracy = efi_data(op).u.get_time.accuracy;
56 		tc->sets_to_zero = !!(efi_data(op).misc &
57 				      XEN_EFI_GET_TIME_SET_CLEARS_NS);
58 	}
59 
60 	return efi_data(op).status;
61 }
62 
63 static efi_status_t xen_efi_set_time(efi_time_t *tm)
64 {
65 	struct xen_platform_op op = INIT_EFI_OP(set_time);
66 
67 	BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.set_time));
68 	memcpy(&efi_data(op).u.set_time, tm, sizeof(*tm));
69 
70 	if (HYPERVISOR_dom0_op(&op) < 0)
71 		return EFI_UNSUPPORTED;
72 
73 	return efi_data(op).status;
74 }
75 
76 static efi_status_t xen_efi_get_wakeup_time(efi_bool_t *enabled,
77 					    efi_bool_t *pending,
78 					    efi_time_t *tm)
79 {
80 	struct xen_platform_op op = INIT_EFI_OP(get_wakeup_time);
81 
82 	if (HYPERVISOR_dom0_op(&op) < 0)
83 		return EFI_UNSUPPORTED;
84 
85 	if (tm) {
86 		BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.get_wakeup_time));
87 		memcpy(tm, &efi_data(op).u.get_wakeup_time, sizeof(*tm));
88 	}
89 
90 	if (enabled)
91 		*enabled = !!(efi_data(op).misc & XEN_EFI_GET_WAKEUP_TIME_ENABLED);
92 
93 	if (pending)
94 		*pending = !!(efi_data(op).misc & XEN_EFI_GET_WAKEUP_TIME_PENDING);
95 
96 	return efi_data(op).status;
97 }
98 
99 static efi_status_t xen_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
100 {
101 	struct xen_platform_op op = INIT_EFI_OP(set_wakeup_time);
102 
103 	BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.set_wakeup_time));
104 	if (enabled)
105 		efi_data(op).misc = XEN_EFI_SET_WAKEUP_TIME_ENABLE;
106 	if (tm)
107 		memcpy(&efi_data(op).u.set_wakeup_time, tm, sizeof(*tm));
108 	else
109 		efi_data(op).misc |= XEN_EFI_SET_WAKEUP_TIME_ENABLE_ONLY;
110 
111 	if (HYPERVISOR_dom0_op(&op) < 0)
112 		return EFI_UNSUPPORTED;
113 
114 	return efi_data(op).status;
115 }
116 
117 static efi_status_t xen_efi_get_variable(efi_char16_t *name,
118 					 efi_guid_t *vendor,
119 					 u32 *attr,
120 					 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_dom0_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 
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_dom0_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 
165 static efi_status_t xen_efi_set_variable(efi_char16_t *name,
166 					 efi_guid_t *vendor,
167 					 u32 attr,
168 					 unsigned long data_size,
169 					 void *data)
170 {
171 	struct xen_platform_op op = INIT_EFI_OP(set_variable);
172 
173 	set_xen_guest_handle(efi_data(op).u.set_variable.name, name);
174 	efi_data(op).misc = attr;
175 	BUILD_BUG_ON(sizeof(*vendor) !=
176 		     sizeof(efi_data(op).u.set_variable.vendor_guid));
177 	memcpy(&efi_data(op).u.set_variable.vendor_guid, vendor, sizeof(*vendor));
178 	efi_data(op).u.set_variable.size = data_size;
179 	set_xen_guest_handle(efi_data(op).u.set_variable.data, data);
180 
181 	if (HYPERVISOR_dom0_op(&op) < 0)
182 		return EFI_UNSUPPORTED;
183 
184 	return efi_data(op).status;
185 }
186 
187 static efi_status_t xen_efi_query_variable_info(u32 attr,
188 						u64 *storage_space,
189 						u64 *remaining_space,
190 						u64 *max_variable_size)
191 {
192 	struct xen_platform_op op = INIT_EFI_OP(query_variable_info);
193 
194 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
195 		return EFI_UNSUPPORTED;
196 
197 	efi_data(op).u.query_variable_info.attr = attr;
198 
199 	if (HYPERVISOR_dom0_op(&op) < 0)
200 		return EFI_UNSUPPORTED;
201 
202 	*storage_space = efi_data(op).u.query_variable_info.max_store_size;
203 	*remaining_space = efi_data(op).u.query_variable_info.remain_store_size;
204 	*max_variable_size = efi_data(op).u.query_variable_info.max_size;
205 
206 	return efi_data(op).status;
207 }
208 
209 static efi_status_t xen_efi_get_next_high_mono_count(u32 *count)
210 {
211 	struct xen_platform_op op = INIT_EFI_OP(get_next_high_monotonic_count);
212 
213 	if (HYPERVISOR_dom0_op(&op) < 0)
214 		return EFI_UNSUPPORTED;
215 
216 	*count = efi_data(op).misc;
217 
218 	return efi_data(op).status;
219 }
220 
221 static efi_status_t xen_efi_update_capsule(efi_capsule_header_t **capsules,
222 					   unsigned long count,
223 					   unsigned long sg_list)
224 {
225 	struct xen_platform_op op = INIT_EFI_OP(update_capsule);
226 
227 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
228 		return EFI_UNSUPPORTED;
229 
230 	set_xen_guest_handle(efi_data(op).u.update_capsule.capsule_header_array,
231 			     capsules);
232 	efi_data(op).u.update_capsule.capsule_count = count;
233 	efi_data(op).u.update_capsule.sg_list = sg_list;
234 
235 	if (HYPERVISOR_dom0_op(&op) < 0)
236 		return EFI_UNSUPPORTED;
237 
238 	return efi_data(op).status;
239 }
240 
241 static efi_status_t xen_efi_query_capsule_caps(efi_capsule_header_t **capsules,
242 					       unsigned long count,
243 					       u64 *max_size,
244 					       int *reset_type)
245 {
246 	struct xen_platform_op op = INIT_EFI_OP(query_capsule_capabilities);
247 
248 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
249 		return EFI_UNSUPPORTED;
250 
251 	set_xen_guest_handle(efi_data(op).u.query_capsule_capabilities.capsule_header_array,
252 					capsules);
253 	efi_data(op).u.query_capsule_capabilities.capsule_count = count;
254 
255 	if (HYPERVISOR_dom0_op(&op) < 0)
256 		return EFI_UNSUPPORTED;
257 
258 	*max_size = efi_data(op).u.query_capsule_capabilities.max_capsule_size;
259 	*reset_type = efi_data(op).u.query_capsule_capabilities.reset_type;
260 
261 	return efi_data(op).status;
262 }
263 
264 static efi_char16_t vendor[100] __initdata;
265 
266 static efi_system_table_t efi_systab_xen __initdata = {
267 	.hdr = {
268 		.signature	= EFI_SYSTEM_TABLE_SIGNATURE,
269 		.revision	= 0, /* Initialized later. */
270 		.headersize	= 0, /* Ignored by Linux Kernel. */
271 		.crc32		= 0, /* Ignored by Linux Kernel. */
272 		.reserved	= 0
273 	},
274 	.fw_vendor	= EFI_INVALID_TABLE_ADDR, /* Initialized later. */
275 	.fw_revision	= 0,			  /* Initialized later. */
276 	.con_in_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
277 	.con_in		= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
278 	.con_out_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
279 	.con_out	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
280 	.stderr_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
281 	.stderr		= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
282 	.runtime	= (efi_runtime_services_t *)EFI_INVALID_TABLE_ADDR,
283 						  /* Not used under Xen. */
284 	.boottime	= (efi_boot_services_t *)EFI_INVALID_TABLE_ADDR,
285 						  /* Not used under Xen. */
286 	.nr_tables	= 0,			  /* Initialized later. */
287 	.tables		= EFI_INVALID_TABLE_ADDR  /* Initialized later. */
288 };
289 
290 static const struct efi efi_xen __initconst = {
291 	.systab                   = NULL, /* Initialized later. */
292 	.runtime_version	  = 0,    /* Initialized later. */
293 	.mps                      = EFI_INVALID_TABLE_ADDR,
294 	.acpi                     = EFI_INVALID_TABLE_ADDR,
295 	.acpi20                   = EFI_INVALID_TABLE_ADDR,
296 	.smbios                   = EFI_INVALID_TABLE_ADDR,
297 	.smbios3                  = EFI_INVALID_TABLE_ADDR,
298 	.sal_systab               = EFI_INVALID_TABLE_ADDR,
299 	.boot_info                = EFI_INVALID_TABLE_ADDR,
300 	.hcdp                     = EFI_INVALID_TABLE_ADDR,
301 	.uga                      = EFI_INVALID_TABLE_ADDR,
302 	.uv_systab                = EFI_INVALID_TABLE_ADDR,
303 	.fw_vendor                = EFI_INVALID_TABLE_ADDR,
304 	.runtime                  = EFI_INVALID_TABLE_ADDR,
305 	.config_table             = EFI_INVALID_TABLE_ADDR,
306 	.get_time                 = xen_efi_get_time,
307 	.set_time                 = xen_efi_set_time,
308 	.get_wakeup_time          = xen_efi_get_wakeup_time,
309 	.set_wakeup_time          = xen_efi_set_wakeup_time,
310 	.get_variable             = xen_efi_get_variable,
311 	.get_next_variable        = xen_efi_get_next_variable,
312 	.set_variable             = xen_efi_set_variable,
313 	.query_variable_info      = xen_efi_query_variable_info,
314 	.update_capsule           = xen_efi_update_capsule,
315 	.query_capsule_caps       = xen_efi_query_capsule_caps,
316 	.get_next_high_mono_count = xen_efi_get_next_high_mono_count,
317 	.reset_system             = NULL, /* Functionality provided by Xen. */
318 	.set_virtual_address_map  = NULL, /* Not used under Xen. */
319 	.memmap                   = NULL, /* Not used under Xen. */
320 	.flags			  = 0     /* Initialized later. */
321 };
322 
323 efi_system_table_t __init *xen_efi_probe(void)
324 {
325 	struct xen_platform_op op = {
326 		.cmd = XENPF_firmware_info,
327 		.u.firmware_info = {
328 			.type = XEN_FW_EFI_INFO,
329 			.index = XEN_FW_EFI_CONFIG_TABLE
330 		}
331 	};
332 	union xenpf_efi_info *info = &op.u.firmware_info.u.efi_info;
333 
334 	if (!xen_initial_domain() || HYPERVISOR_dom0_op(&op) < 0)
335 		return NULL;
336 
337 	/* Here we know that Xen runs on EFI platform. */
338 
339 	efi = efi_xen;
340 
341 	efi_systab_xen.tables = info->cfg.addr;
342 	efi_systab_xen.nr_tables = info->cfg.nent;
343 
344 	op.cmd = XENPF_firmware_info;
345 	op.u.firmware_info.type = XEN_FW_EFI_INFO;
346 	op.u.firmware_info.index = XEN_FW_EFI_VENDOR;
347 	info->vendor.bufsz = sizeof(vendor);
348 	set_xen_guest_handle(info->vendor.name, vendor);
349 
350 	if (HYPERVISOR_dom0_op(&op) == 0) {
351 		efi_systab_xen.fw_vendor = __pa_symbol(vendor);
352 		efi_systab_xen.fw_revision = info->vendor.revision;
353 	} else
354 		efi_systab_xen.fw_vendor = __pa_symbol(L"UNKNOWN");
355 
356 	op.cmd = XENPF_firmware_info;
357 	op.u.firmware_info.type = XEN_FW_EFI_INFO;
358 	op.u.firmware_info.index = XEN_FW_EFI_VERSION;
359 
360 	if (HYPERVISOR_dom0_op(&op) == 0)
361 		efi_systab_xen.hdr.revision = info->version;
362 
363 	op.cmd = XENPF_firmware_info;
364 	op.u.firmware_info.type = XEN_FW_EFI_INFO;
365 	op.u.firmware_info.index = XEN_FW_EFI_RT_VERSION;
366 
367 	if (HYPERVISOR_dom0_op(&op) == 0)
368 		efi.runtime_version = info->version;
369 
370 	return &efi_systab_xen;
371 }
372