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/page.h>
30#include <xen/xen.h>
31#include <xen/xen-ops.h>
32
33#include <asm/page.h>
34
35#include <asm/xen/hypercall.h>
36
37#define INIT_EFI_OP(name) \
38 {.cmd = XENPF_efi_runtime_call, \
39 .u.efi_runtime_call.function = XEN_EFI_##name, \
40 .u.efi_runtime_call.misc = 0}
41
42#define efi_data(op) (op.u.efi_runtime_call)
43
44static efi_status_t xen_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
45{
46 struct xen_platform_op op = INIT_EFI_OP(get_time);
47
48 if (HYPERVISOR_platform_op(op: &op) < 0)
49 return EFI_UNSUPPORTED;
50
51 if (tm) {
52 BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.get_time.time));
53 memcpy(tm, &efi_data(op).u.get_time.time, sizeof(*tm));
54 }
55
56 if (tc) {
57 tc->resolution = efi_data(op).u.get_time.resolution;
58 tc->accuracy = efi_data(op).u.get_time.accuracy;
59 tc->sets_to_zero = !!(efi_data(op).misc &
60 XEN_EFI_GET_TIME_SET_CLEARS_NS);
61 }
62
63 return efi_data(op).status;
64}
65
66static efi_status_t xen_efi_set_time(efi_time_t *tm)
67{
68 struct xen_platform_op op = INIT_EFI_OP(set_time);
69
70 BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.set_time));
71 memcpy(&efi_data(op).u.set_time, tm, sizeof(*tm));
72
73 if (HYPERVISOR_platform_op(op: &op) < 0)
74 return EFI_UNSUPPORTED;
75
76 return efi_data(op).status;
77}
78
79static efi_status_t xen_efi_get_wakeup_time(efi_bool_t *enabled,
80 efi_bool_t *pending,
81 efi_time_t *tm)
82{
83 struct xen_platform_op op = INIT_EFI_OP(get_wakeup_time);
84
85 if (HYPERVISOR_platform_op(op: &op) < 0)
86 return EFI_UNSUPPORTED;
87
88 if (tm) {
89 BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.get_wakeup_time));
90 memcpy(tm, &efi_data(op).u.get_wakeup_time, sizeof(*tm));
91 }
92
93 if (enabled)
94 *enabled = !!(efi_data(op).misc & XEN_EFI_GET_WAKEUP_TIME_ENABLED);
95
96 if (pending)
97 *pending = !!(efi_data(op).misc & XEN_EFI_GET_WAKEUP_TIME_PENDING);
98
99 return efi_data(op).status;
100}
101
102static efi_status_t xen_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
103{
104 struct xen_platform_op op = INIT_EFI_OP(set_wakeup_time);
105
106 BUILD_BUG_ON(sizeof(*tm) != sizeof(efi_data(op).u.set_wakeup_time));
107 if (enabled)
108 efi_data(op).misc = XEN_EFI_SET_WAKEUP_TIME_ENABLE;
109 if (tm)
110 memcpy(&efi_data(op).u.set_wakeup_time, tm, sizeof(*tm));
111 else
112 efi_data(op).misc |= XEN_EFI_SET_WAKEUP_TIME_ENABLE_ONLY;
113
114 if (HYPERVISOR_platform_op(op: &op) < 0)
115 return EFI_UNSUPPORTED;
116
117 return efi_data(op).status;
118}
119
120static efi_status_t xen_efi_get_variable(efi_char16_t *name, efi_guid_t *vendor,
121 u32 *attr, unsigned long *data_size,
122 void *data)
123{
124 struct xen_platform_op op = INIT_EFI_OP(get_variable);
125
126 set_xen_guest_handle(efi_data(op).u.get_variable.name, name);
127 BUILD_BUG_ON(sizeof(*vendor) !=
128 sizeof(efi_data(op).u.get_variable.vendor_guid));
129 memcpy(&efi_data(op).u.get_variable.vendor_guid, vendor, sizeof(*vendor));
130 efi_data(op).u.get_variable.size = *data_size;
131 set_xen_guest_handle(efi_data(op).u.get_variable.data, data);
132
133 if (HYPERVISOR_platform_op(op: &op) < 0)
134 return EFI_UNSUPPORTED;
135
136 *data_size = efi_data(op).u.get_variable.size;
137 if (attr)
138 *attr = efi_data(op).misc;
139
140 return efi_data(op).status;
141}
142
143static efi_status_t xen_efi_get_next_variable(unsigned long *name_size,
144 efi_char16_t *name,
145 efi_guid_t *vendor)
146{
147 struct xen_platform_op op = INIT_EFI_OP(get_next_variable_name);
148
149 efi_data(op).u.get_next_variable_name.size = *name_size;
150 set_xen_guest_handle(efi_data(op).u.get_next_variable_name.name, name);
151 BUILD_BUG_ON(sizeof(*vendor) !=
152 sizeof(efi_data(op).u.get_next_variable_name.vendor_guid));
153 memcpy(&efi_data(op).u.get_next_variable_name.vendor_guid, vendor,
154 sizeof(*vendor));
155
156 if (HYPERVISOR_platform_op(op: &op) < 0)
157 return EFI_UNSUPPORTED;
158
159 *name_size = efi_data(op).u.get_next_variable_name.size;
160 memcpy(vendor, &efi_data(op).u.get_next_variable_name.vendor_guid,
161 sizeof(*vendor));
162
163 return efi_data(op).status;
164}
165
166static efi_status_t xen_efi_set_variable(efi_char16_t *name, efi_guid_t *vendor,
167 u32 attr, unsigned long data_size,
168 void *data)
169{
170 struct xen_platform_op op = INIT_EFI_OP(set_variable);
171
172 set_xen_guest_handle(efi_data(op).u.set_variable.name, name);
173 efi_data(op).misc = attr;
174 BUILD_BUG_ON(sizeof(*vendor) !=
175 sizeof(efi_data(op).u.set_variable.vendor_guid));
176 memcpy(&efi_data(op).u.set_variable.vendor_guid, vendor, sizeof(*vendor));
177 efi_data(op).u.set_variable.size = data_size;
178 set_xen_guest_handle(efi_data(op).u.set_variable.data, data);
179
180 if (HYPERVISOR_platform_op(op: &op) < 0)
181 return EFI_UNSUPPORTED;
182
183 return efi_data(op).status;
184}
185
186static efi_status_t xen_efi_query_variable_info(u32 attr, u64 *storage_space,
187 u64 *remaining_space,
188 u64 *max_variable_size)
189{
190 struct xen_platform_op op = INIT_EFI_OP(query_variable_info);
191
192 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
193 return EFI_UNSUPPORTED;
194
195 efi_data(op).u.query_variable_info.attr = attr;
196
197 if (HYPERVISOR_platform_op(op: &op) < 0)
198 return EFI_UNSUPPORTED;
199
200 *storage_space = efi_data(op).u.query_variable_info.max_store_size;
201 *remaining_space = efi_data(op).u.query_variable_info.remain_store_size;
202 *max_variable_size = efi_data(op).u.query_variable_info.max_size;
203
204 return efi_data(op).status;
205}
206
207static efi_status_t xen_efi_get_next_high_mono_count(u32 *count)
208{
209 struct xen_platform_op op = INIT_EFI_OP(get_next_high_monotonic_count);
210
211 if (HYPERVISOR_platform_op(op: &op) < 0)
212 return EFI_UNSUPPORTED;
213
214 *count = efi_data(op).misc;
215
216 return efi_data(op).status;
217}
218
219static efi_status_t xen_efi_update_capsule(efi_capsule_header_t **capsules,
220 unsigned long count, unsigned long sg_list)
221{
222 struct xen_platform_op op = INIT_EFI_OP(update_capsule);
223
224 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
225 return EFI_UNSUPPORTED;
226
227 set_xen_guest_handle(efi_data(op).u.update_capsule.capsule_header_array,
228 capsules);
229 efi_data(op).u.update_capsule.capsule_count = count;
230 efi_data(op).u.update_capsule.sg_list = sg_list;
231
232 if (HYPERVISOR_platform_op(op: &op) < 0)
233 return EFI_UNSUPPORTED;
234
235 return efi_data(op).status;
236}
237
238static efi_status_t xen_efi_query_capsule_caps(efi_capsule_header_t **capsules,
239 unsigned long count, u64 *max_size, int *reset_type)
240{
241 struct xen_platform_op op = INIT_EFI_OP(query_capsule_capabilities);
242
243 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
244 return EFI_UNSUPPORTED;
245
246 set_xen_guest_handle(efi_data(op).u.query_capsule_capabilities.capsule_header_array,
247 capsules);
248 efi_data(op).u.query_capsule_capabilities.capsule_count = count;
249
250 if (HYPERVISOR_platform_op(op: &op) < 0)
251 return EFI_UNSUPPORTED;
252
253 *max_size = efi_data(op).u.query_capsule_capabilities.max_capsule_size;
254 *reset_type = efi_data(op).u.query_capsule_capabilities.reset_type;
255
256 return efi_data(op).status;
257}
258
259static void xen_efi_reset_system(int reset_type, efi_status_t status,
260 unsigned long data_size, efi_char16_t *data)
261{
262 switch (reset_type) {
263 case EFI_RESET_COLD:
264 case EFI_RESET_WARM:
265 xen_reboot(SHUTDOWN_reboot);
266 break;
267 case EFI_RESET_SHUTDOWN:
268 xen_reboot(SHUTDOWN_poweroff);
269 break;
270 default:
271 BUG();
272 }
273}
274
275/*
276 * Set XEN EFI runtime services function pointers. Other fields of struct efi,
277 * e.g. efi.systab, will be set like normal EFI.
278 */
279void __init xen_efi_runtime_setup(void)
280{
281 efi.get_time = xen_efi_get_time;
282 efi.set_time = xen_efi_set_time;
283 efi.get_wakeup_time = xen_efi_get_wakeup_time;
284 efi.set_wakeup_time = xen_efi_set_wakeup_time;
285 efi.get_variable = xen_efi_get_variable;
286 efi.get_next_variable = xen_efi_get_next_variable;
287 efi.set_variable = xen_efi_set_variable;
288 efi.set_variable_nonblocking = xen_efi_set_variable;
289 efi.query_variable_info = xen_efi_query_variable_info;
290 efi.query_variable_info_nonblocking = xen_efi_query_variable_info;
291 efi.update_capsule = xen_efi_update_capsule;
292 efi.query_capsule_caps = xen_efi_query_capsule_caps;
293 efi.get_next_high_mono_count = xen_efi_get_next_high_mono_count;
294 efi.reset_system = xen_efi_reset_system;
295}
296
297int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
298{
299 static_assert(XEN_PAGE_SHIFT == EFI_PAGE_SHIFT,
300 "Mismatch between EFI_PAGE_SHIFT and XEN_PAGE_SHIFT");
301 struct xen_platform_op op;
302 union xenpf_efi_info *info = &op.u.firmware_info.u.efi_info;
303 int rc;
304
305 if (!efi_enabled(EFI_PARAVIRT) || efi_enabled(EFI_MEMMAP))
306 return __efi_mem_desc_lookup(phys_addr, out_md);
307 phys_addr &= ~(u64)(EFI_PAGE_SIZE - 1);
308 op = (struct xen_platform_op) {
309 .cmd = XENPF_firmware_info,
310 .u.firmware_info = {
311 .type = XEN_FW_EFI_INFO,
312 .index = XEN_FW_EFI_MEM_INFO,
313 .u.efi_info.mem.addr = phys_addr,
314 .u.efi_info.mem.size = U64_MAX - phys_addr,
315 },
316 };
317
318 rc = HYPERVISOR_platform_op(op: &op);
319 if (rc) {
320 pr_warn("Failed to lookup header 0x%llx in Xen memory map: error %d\n",
321 phys_addr, rc);
322 }
323
324 out_md->phys_addr = info->mem.addr;
325 out_md->num_pages = info->mem.size >> EFI_PAGE_SHIFT;
326 out_md->type = info->mem.type;
327 out_md->attribute = info->mem.attr;
328
329 return 0;
330}
331
332bool __init xen_efi_config_table_is_usable(const efi_guid_t *guid,
333 unsigned long table)
334{
335 efi_memory_desc_t md;
336 int rc;
337
338 if (!efi_enabled(EFI_PARAVIRT))
339 return true;
340
341 rc = efi_mem_desc_lookup(phys_addr: table, out_md: &md);
342 if (rc)
343 return false;
344
345 switch (md.type) {
346 case EFI_RUNTIME_SERVICES_CODE:
347 case EFI_RUNTIME_SERVICES_DATA:
348 case EFI_ACPI_RECLAIM_MEMORY:
349 case EFI_ACPI_MEMORY_NVS:
350 case EFI_RESERVED_TYPE:
351 return true;
352 default:
353 return false;
354 }
355}
356

source code of linux/drivers/xen/efi.c