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) < 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) < 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) < 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) < 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) < 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) < 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) < 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) < 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) < 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) < 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) < 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);
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(table, &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