xref: /openbmc/qemu/hw/i386/pc_sysfw.c (revision ee3b34cd)
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 "sysemu/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 "sysemu/kvm.h"
39 #include "sev.h"
40 
41 #define FLASH_SECTOR_SIZE 4096
42 
43 static void pc_isa_bios_init(MemoryRegion *rom_memory,
44                              MemoryRegion *flash_mem,
45                              int ram_size)
46 {
47     int isa_bios_size;
48     MemoryRegion *isa_bios;
49     uint64_t flash_size;
50     void *flash_ptr, *isa_bios_ptr;
51 
52     flash_size = memory_region_size(flash_mem);
53 
54     /* map the last 128KB of the BIOS in ISA space */
55     isa_bios_size = MIN(flash_size, 128 * KiB);
56     isa_bios = g_malloc(sizeof(*isa_bios));
57     memory_region_init_ram(isa_bios, NULL, "isa-bios", isa_bios_size,
58                            &error_fatal);
59     memory_region_add_subregion_overlap(rom_memory,
60                                         0x100000 - isa_bios_size,
61                                         isa_bios,
62                                         1);
63 
64     /* copy ISA rom image from top of flash memory */
65     flash_ptr = memory_region_get_ram_ptr(flash_mem);
66     isa_bios_ptr = memory_region_get_ram_ptr(isa_bios);
67     memcpy(isa_bios_ptr,
68            ((uint8_t*)flash_ptr) + (flash_size - isa_bios_size),
69            isa_bios_size);
70 
71     memory_region_set_readonly(isa_bios, true);
72 }
73 
74 static PFlashCFI01 *pc_pflash_create(PCMachineState *pcms,
75                                      const char *name,
76                                      const char *alias_prop_name)
77 {
78     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI01);
79 
80     qdev_prop_set_uint64(dev, "sector-length", FLASH_SECTOR_SIZE);
81     qdev_prop_set_uint8(dev, "width", 1);
82     qdev_prop_set_string(dev, "name", name);
83     object_property_add_child(OBJECT(pcms), name, OBJECT(dev));
84     object_property_add_alias(OBJECT(pcms), alias_prop_name,
85                               OBJECT(dev), "drive");
86     /*
87      * The returned reference is tied to the child property and
88      * will be removed with object_unparent.
89      */
90     object_unref(OBJECT(dev));
91     return PFLASH_CFI01(dev);
92 }
93 
94 static void pc_system_flash_cleanup_unused(PCMachineState *pcms)
95 {
96     char *prop_name;
97     int i;
98 
99     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
100 
101     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
102         if (!qdev_is_realized(DEVICE(pcms->flash[i]))) {
103             prop_name = g_strdup_printf("pflash%d", i);
104             object_property_del(OBJECT(pcms), prop_name);
105             g_free(prop_name);
106             object_unparent(OBJECT(pcms->flash[i]));
107             pcms->flash[i] = NULL;
108         }
109     }
110 }
111 
112 /*
113  * Map the pcms->flash[] from 4GiB downward, and realize.
114  * Map them in descending order, i.e. pcms->flash[0] at the top,
115  * without gaps.
116  * Stop at the first pcms->flash[0] lacking a block backend.
117  * Set each flash's size from its block backend.  Fatal error if the
118  * size isn't a non-zero multiple of 4KiB, or the total size exceeds
119  * pcms->max_fw_size.
120  *
121  * If pcms->flash[0] has a block backend, its memory is passed to
122  * pc_isa_bios_init().  Merging several flash devices for isa-bios is
123  * not supported.
124  */
125 static void pc_system_flash_map(PCMachineState *pcms,
126                                 MemoryRegion *rom_memory)
127 {
128     hwaddr total_size = 0;
129     int i;
130     BlockBackend *blk;
131     int64_t size;
132     PFlashCFI01 *system_flash;
133     MemoryRegion *flash_mem;
134     void *flash_ptr;
135     int flash_size;
136 
137     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
138 
139     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
140         system_flash = pcms->flash[i];
141         blk = pflash_cfi01_get_blk(system_flash);
142         if (!blk) {
143             break;
144         }
145         size = blk_getlength(blk);
146         if (size < 0) {
147             error_report("can't get size of block device %s: %s",
148                          blk_name(blk), strerror(-size));
149             exit(1);
150         }
151         if (size == 0 || !QEMU_IS_ALIGNED(size, FLASH_SECTOR_SIZE)) {
152             error_report("system firmware block device %s has invalid size "
153                          "%" PRId64,
154                          blk_name(blk), size);
155             info_report("its size must be a non-zero multiple of 0x%x",
156                         FLASH_SECTOR_SIZE);
157             exit(1);
158         }
159         if ((hwaddr)size != size
160             || total_size > HWADDR_MAX - size
161             || total_size + size > pcms->max_fw_size) {
162             error_report("combined size of system firmware exceeds "
163                          "%" PRIu64 " bytes",
164                          pcms->max_fw_size);
165             exit(1);
166         }
167 
168         total_size += size;
169         qdev_prop_set_uint32(DEVICE(system_flash), "num-blocks",
170                              size / FLASH_SECTOR_SIZE);
171         sysbus_realize_and_unref(SYS_BUS_DEVICE(system_flash), &error_fatal);
172         sysbus_mmio_map(SYS_BUS_DEVICE(system_flash), 0,
173                         0x100000000ULL - total_size);
174 
175         if (i == 0) {
176             flash_mem = pflash_cfi01_get_memory(system_flash);
177             pc_isa_bios_init(rom_memory, flash_mem, size);
178 
179             /* Encrypt the pflash boot ROM */
180             if (sev_enabled()) {
181                 flash_ptr = memory_region_get_ram_ptr(flash_mem);
182                 flash_size = memory_region_size(flash_mem);
183                 x86_firmware_configure(flash_ptr, flash_size);
184             }
185         }
186     }
187 }
188 
189 void pc_system_firmware_init(PCMachineState *pcms,
190                              MemoryRegion *rom_memory)
191 {
192     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
193     int i;
194     BlockBackend *pflash_blk[ARRAY_SIZE(pcms->flash)];
195 
196     if (!pcmc->pci_enabled) {
197         x86_bios_rom_init(MACHINE(pcms), "bios.bin", rom_memory, true);
198         return;
199     }
200 
201     pcms->flash[0] = pc_pflash_create(pcms, "system.flash0", "pflash0");
202     pcms->flash[1] = pc_pflash_create(pcms, "system.flash1", "pflash1");
203 
204     /* Map legacy -drive if=pflash to machine properties */
205     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
206         pflash_cfi01_legacy_drive(pcms->flash[i],
207                                   drive_get(IF_PFLASH, 0, i));
208         pflash_blk[i] = pflash_cfi01_get_blk(pcms->flash[i]);
209     }
210 
211     /* Reject gaps */
212     for (i = 1; i < ARRAY_SIZE(pcms->flash); i++) {
213         if (pflash_blk[i] && !pflash_blk[i - 1]) {
214             error_report("pflash%d requires pflash%d", i, i - 1);
215             exit(1);
216         }
217     }
218 
219     if (!pflash_blk[0]) {
220         /* Machine property pflash0 not set, use ROM mode */
221         x86_bios_rom_init(MACHINE(pcms), "bios.bin", rom_memory, false);
222     } else {
223         if (kvm_enabled() && !kvm_readonly_mem_enabled()) {
224             /*
225              * Older KVM cannot execute from device memory. So, flash
226              * memory cannot be used unless the readonly memory kvm
227              * capability is present.
228              */
229             error_report("pflash with kvm requires KVM readonly memory support");
230             exit(1);
231         }
232 
233         pc_system_flash_map(pcms, rom_memory);
234     }
235 
236     pc_system_flash_cleanup_unused(pcms);
237 }
238 
239 void x86_firmware_configure(void *ptr, int size)
240 {
241     int ret;
242 
243     /*
244      * OVMF places a GUIDed structures in the flash, so
245      * search for them
246      */
247     pc_system_parse_ovmf_flash(ptr, size);
248 
249     if (sev_enabled()) {
250         ret = sev_es_save_reset_vector(ptr, size);
251         if (ret) {
252             error_report("failed to locate and/or save reset vector");
253             exit(1);
254         }
255 
256         sev_encrypt_flash(ptr, size, &error_fatal);
257     }
258 }
259