xref: /qemu/hw/i386/pc_sysfw.c (revision 98721058d6d50ef218e0c26e4f67c8ef96965859)
1 /*
2  * QEMU PC System Firmware
3  *
4  * Copyright (c) 2003-2004 Fabrice Bellard
5  * Copyright (c) 2011-2012 Intel Corporation
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 #include "qapi/error.h"
28 #include "system/block-backend.h"
29 #include "qemu/error-report.h"
30 #include "qemu/option.h"
31 #include "qemu/units.h"
32 #include "hw/sysbus.h"
33 #include "hw/i386/x86.h"
34 #include "hw/i386/pc.h"
35 #include "hw/loader.h"
36 #include "hw/qdev-properties.h"
37 #include "hw/block/flash.h"
38 #include "system/kvm.h"
39 #include "target/i386/sev.h"
40 #include "kvm/tdx.h"
41 
42 #define FLASH_SECTOR_SIZE 4096
43 
pc_isa_bios_init(PCMachineState * pcms,MemoryRegion * isa_bios,MemoryRegion * rom_memory,MemoryRegion * flash_mem)44 static void pc_isa_bios_init(PCMachineState *pcms, MemoryRegion *isa_bios,
45                              MemoryRegion *rom_memory, MemoryRegion *flash_mem)
46 {
47     int isa_bios_size;
48     uint64_t flash_size;
49     void *flash_ptr, *isa_bios_ptr;
50 
51     flash_size = memory_region_size(flash_mem);
52 
53     /* map the last 128KB of the BIOS in ISA space */
54     isa_bios_size = MIN(flash_size, 128 * KiB);
55     if (machine_require_guest_memfd(MACHINE(pcms))) {
56         memory_region_init_ram_guest_memfd(isa_bios, NULL, "isa-bios",
57                                            isa_bios_size, &error_fatal);
58     } else {
59         memory_region_init_ram(isa_bios, NULL, "isa-bios", isa_bios_size,
60                                &error_fatal);
61     }
62     memory_region_add_subregion_overlap(rom_memory,
63                                         0x100000 - isa_bios_size,
64                                         isa_bios,
65                                         1);
66 
67     /* copy ISA rom image from top of flash memory */
68     flash_ptr = memory_region_get_ram_ptr(flash_mem);
69     isa_bios_ptr = memory_region_get_ram_ptr(isa_bios);
70     memcpy(isa_bios_ptr,
71            ((uint8_t*)flash_ptr) + (flash_size - isa_bios_size),
72            isa_bios_size);
73 
74     if (!machine_require_guest_memfd(current_machine)) {
75         memory_region_set_readonly(isa_bios, true);
76     }
77 }
78 
pc_pflash_create(PCMachineState * pcms,const char * name,const char * alias_prop_name)79 static PFlashCFI01 *pc_pflash_create(PCMachineState *pcms,
80                                      const char *name,
81                                      const char *alias_prop_name)
82 {
83     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI01);
84 
85     qdev_prop_set_uint64(dev, "sector-length", FLASH_SECTOR_SIZE);
86     qdev_prop_set_uint8(dev, "width", 1);
87     qdev_prop_set_string(dev, "name", name);
88     object_property_add_child(OBJECT(pcms), name, OBJECT(dev));
89     object_property_add_alias(OBJECT(pcms), alias_prop_name,
90                               OBJECT(dev), "drive");
91     /*
92      * The returned reference is tied to the child property and
93      * will be removed with object_unparent.
94      */
95     object_unref(OBJECT(dev));
96     return PFLASH_CFI01(dev);
97 }
98 
pc_system_flash_create(PCMachineState * pcms)99 void pc_system_flash_create(PCMachineState *pcms)
100 {
101     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
102 
103     if (pcmc->pci_enabled) {
104         pcms->flash[0] = pc_pflash_create(pcms, "system.flash0",
105                                           "pflash0");
106         pcms->flash[1] = pc_pflash_create(pcms, "system.flash1",
107                                           "pflash1");
108     }
109 }
110 
pc_system_flash_cleanup_unused(PCMachineState * pcms)111 void pc_system_flash_cleanup_unused(PCMachineState *pcms)
112 {
113     char *prop_name;
114     int i;
115 
116     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
117 
118     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
119         if (!qdev_is_realized(DEVICE(pcms->flash[i]))) {
120             prop_name = g_strdup_printf("pflash%d", i);
121             object_property_del(OBJECT(pcms), prop_name);
122             g_free(prop_name);
123             object_unparent(OBJECT(pcms->flash[i]));
124             pcms->flash[i] = NULL;
125         }
126     }
127 }
128 
129 /*
130  * Map the pcms->flash[] from 4GiB downward, and realize.
131  * Map them in descending order, i.e. pcms->flash[0] at the top,
132  * without gaps.
133  * Stop at the first pcms->flash[0] lacking a block backend.
134  * Set each flash's size from its block backend.  Fatal error if the
135  * size isn't a non-zero multiple of 4KiB, or the total size exceeds
136  * pcms->max_fw_size.
137  *
138  * If pcms->flash[0] has a block backend, its memory is passed to
139  * pc_isa_bios_init().  Merging several flash devices for isa-bios is
140  * not supported.
141  */
pc_system_flash_map(PCMachineState * pcms,MemoryRegion * rom_memory)142 static void pc_system_flash_map(PCMachineState *pcms,
143                                 MemoryRegion *rom_memory)
144 {
145     X86MachineState *x86ms = X86_MACHINE(pcms);
146     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
147     hwaddr total_size = 0;
148     int i;
149     BlockBackend *blk;
150     int64_t size;
151     PFlashCFI01 *system_flash;
152     MemoryRegion *flash_mem;
153     void *flash_ptr;
154     int flash_size;
155 
156     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
157 
158     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
159         hwaddr gpa;
160 
161         system_flash = pcms->flash[i];
162         blk = pflash_cfi01_get_blk(system_flash);
163         if (!blk) {
164             break;
165         }
166         size = blk_getlength(blk);
167         if (size < 0) {
168             error_report("can't get size of block device %s: %s",
169                          blk_name(blk), strerror(-size));
170             exit(1);
171         }
172         if (size == 0 || !QEMU_IS_ALIGNED(size, FLASH_SECTOR_SIZE)) {
173             error_report("system firmware block device %s has invalid size "
174                          "%" PRId64,
175                          blk_name(blk), size);
176             info_report("its size must be a non-zero multiple of 0x%x",
177                         FLASH_SECTOR_SIZE);
178             exit(1);
179         }
180         if ((hwaddr)size != size
181             || total_size > HWADDR_MAX - size
182             || total_size + size > pcms->max_fw_size) {
183             error_report("combined size of system firmware exceeds "
184                          "%" PRIu64 " bytes",
185                          pcms->max_fw_size);
186             exit(1);
187         }
188 
189         total_size += size;
190         gpa = 0x100000000ULL - total_size; /* where the flash is mapped */
191         qdev_prop_set_uint32(DEVICE(system_flash), "num-blocks",
192                              size / FLASH_SECTOR_SIZE);
193         sysbus_realize_and_unref(SYS_BUS_DEVICE(system_flash), &error_fatal);
194         sysbus_mmio_map(SYS_BUS_DEVICE(system_flash), 0, gpa);
195 
196         if (i == 0) {
197             flash_mem = pflash_cfi01_get_memory(system_flash);
198             if (pcmc->isa_bios_alias) {
199                 x86_isa_bios_init(&x86ms->isa_bios, rom_memory, flash_mem,
200                                   true);
201             } else {
202                 pc_isa_bios_init(pcms, &x86ms->isa_bios, rom_memory, flash_mem);
203             }
204 
205             /* Encrypt the pflash boot ROM */
206             if (sev_enabled()) {
207                 flash_ptr = memory_region_get_ram_ptr(flash_mem);
208                 flash_size = memory_region_size(flash_mem);
209                 x86_firmware_configure(gpa, flash_ptr, flash_size);
210             }
211         }
212     }
213 }
214 
pc_system_firmware_init(PCMachineState * pcms,MemoryRegion * rom_memory)215 void pc_system_firmware_init(PCMachineState *pcms,
216                              MemoryRegion *rom_memory)
217 {
218     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
219     int i;
220     BlockBackend *pflash_blk[ARRAY_SIZE(pcms->flash)];
221 
222     if (!pcmc->pci_enabled) {
223         x86_bios_rom_init(X86_MACHINE(pcms), "bios.bin", rom_memory, true);
224         return;
225     }
226 
227     /* Map legacy -drive if=pflash to machine properties */
228     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
229         pflash_cfi01_legacy_drive(pcms->flash[i],
230                                   drive_get(IF_PFLASH, 0, i));
231         pflash_blk[i] = pflash_cfi01_get_blk(pcms->flash[i]);
232     }
233 
234     /* Reject gaps */
235     for (i = 1; i < ARRAY_SIZE(pcms->flash); i++) {
236         if (pflash_blk[i] && !pflash_blk[i - 1]) {
237             error_report("pflash%d requires pflash%d", i, i - 1);
238             exit(1);
239         }
240     }
241 
242     if (!pflash_blk[0]) {
243         /* Machine property pflash0 not set, use ROM mode */
244         x86_bios_rom_init(X86_MACHINE(pcms), "bios.bin", rom_memory, false);
245     } else {
246         if (kvm_enabled() && !kvm_readonly_mem_enabled()) {
247             /*
248              * Older KVM cannot execute from device memory. So, flash
249              * memory cannot be used unless the readonly memory kvm
250              * capability is present.
251              */
252             error_report("pflash with kvm requires KVM readonly memory support");
253             exit(1);
254         }
255 
256         pc_system_flash_map(pcms, rom_memory);
257     }
258 
259     pc_system_flash_cleanup_unused(pcms);
260 }
261 
x86_firmware_configure(hwaddr gpa,void * ptr,int size)262 void x86_firmware_configure(hwaddr gpa, void *ptr, int size)
263 {
264     int ret;
265 
266     /*
267      * OVMF places a GUIDed structures in the flash, so
268      * search for them
269      */
270     pc_system_parse_ovmf_flash(ptr, size);
271 
272     if (sev_enabled()) {
273 
274         /* Copy the SEV metadata table (if it exists) */
275         pc_system_parse_sev_metadata(ptr, size);
276 
277         ret = sev_es_save_reset_vector(ptr, size);
278         if (ret) {
279             error_report("failed to locate and/or save reset vector");
280             exit(1);
281         }
282 
283         sev_encrypt_flash(gpa, ptr, size, &error_fatal);
284     } else if (is_tdx_vm()) {
285         ret = tdx_parse_tdvf(ptr, size);
286         if (ret) {
287             error_report("failed to parse TDVF for TDX VM");
288             exit(1);
289         }
290     }
291 }
292