xref: /openbmc/qemu/hw/i386/pc_sysfw.c (revision 43709a0c)
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 "qemu-common.h"
28 #include "qapi/error.h"
29 #include "sysemu/block-backend.h"
30 #include "qemu/error-report.h"
31 #include "qemu/option.h"
32 #include "qemu/units.h"
33 #include "hw/sysbus.h"
34 #include "hw/i386/x86.h"
35 #include "hw/i386/pc.h"
36 #include "hw/loader.h"
37 #include "hw/qdev-properties.h"
38 #include "hw/block/flash.h"
39 #include "sysemu/kvm.h"
40 #include "sev.h"
41 
42 #define FLASH_SECTOR_SIZE 4096
43 
44 static void pc_isa_bios_init(MemoryRegion *rom_memory,
45                              MemoryRegion *flash_mem,
46                              int ram_size)
47 {
48     int isa_bios_size;
49     MemoryRegion *isa_bios;
50     uint64_t flash_size;
51     void *flash_ptr, *isa_bios_ptr;
52 
53     flash_size = memory_region_size(flash_mem);
54 
55     /* map the last 128KB of the BIOS in ISA space */
56     isa_bios_size = MIN(flash_size, 128 * KiB);
57     isa_bios = g_malloc(sizeof(*isa_bios));
58     memory_region_init_ram(isa_bios, NULL, "isa-bios", isa_bios_size,
59                            &error_fatal);
60     memory_region_add_subregion_overlap(rom_memory,
61                                         0x100000 - isa_bios_size,
62                                         isa_bios,
63                                         1);
64 
65     /* copy ISA rom image from top of flash memory */
66     flash_ptr = memory_region_get_ram_ptr(flash_mem);
67     isa_bios_ptr = memory_region_get_ram_ptr(isa_bios);
68     memcpy(isa_bios_ptr,
69            ((uint8_t*)flash_ptr) + (flash_size - isa_bios_size),
70            isa_bios_size);
71 
72     memory_region_set_readonly(isa_bios, true);
73 }
74 
75 static PFlashCFI01 *pc_pflash_create(PCMachineState *pcms,
76                                      const char *name,
77                                      const char *alias_prop_name)
78 {
79     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI01);
80 
81     qdev_prop_set_uint64(dev, "sector-length", FLASH_SECTOR_SIZE);
82     qdev_prop_set_uint8(dev, "width", 1);
83     qdev_prop_set_string(dev, "name", name);
84     object_property_add_child(OBJECT(pcms), name, OBJECT(dev));
85     object_property_add_alias(OBJECT(pcms), alias_prop_name,
86                               OBJECT(dev), "drive");
87     /*
88      * The returned reference is tied to the child property and
89      * will be removed with object_unparent.
90      */
91     object_unref(OBJECT(dev));
92     return PFLASH_CFI01(dev);
93 }
94 
95 void pc_system_flash_create(PCMachineState *pcms)
96 {
97     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
98 
99     if (pcmc->pci_enabled) {
100         pcms->flash[0] = pc_pflash_create(pcms, "system.flash0",
101                                           "pflash0");
102         pcms->flash[1] = pc_pflash_create(pcms, "system.flash1",
103                                           "pflash1");
104     }
105 }
106 
107 void pc_system_flash_cleanup_unused(PCMachineState *pcms)
108 {
109     char *prop_name;
110     int i;
111     Object *dev_obj;
112 
113     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
114 
115     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
116         dev_obj = OBJECT(pcms->flash[i]);
117         if (!object_property_get_bool(dev_obj, "realized", &error_abort)) {
118             prop_name = g_strdup_printf("pflash%d", i);
119             object_property_del(OBJECT(pcms), prop_name);
120             g_free(prop_name);
121             object_unparent(dev_obj);
122             pcms->flash[i] = NULL;
123         }
124     }
125 }
126 
127 /*
128  * Map the pcms->flash[] from 4GiB downward, and realize.
129  * Map them in descending order, i.e. pcms->flash[0] at the top,
130  * without gaps.
131  * Stop at the first pcms->flash[0] lacking a block backend.
132  * Set each flash's size from its block backend.  Fatal error if the
133  * size isn't a non-zero multiple of 4KiB, or the total size exceeds
134  * pcms->max_fw_size.
135  *
136  * If pcms->flash[0] has a block backend, its memory is passed to
137  * pc_isa_bios_init().  Merging several flash devices for isa-bios is
138  * not supported.
139  */
140 static void pc_system_flash_map(PCMachineState *pcms,
141                                 MemoryRegion *rom_memory)
142 {
143     hwaddr total_size = 0;
144     int i;
145     BlockBackend *blk;
146     int64_t size;
147     PFlashCFI01 *system_flash;
148     MemoryRegion *flash_mem;
149     void *flash_ptr;
150     int flash_size;
151     int ret;
152 
153     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
154 
155     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
156         system_flash = pcms->flash[i];
157         blk = pflash_cfi01_get_blk(system_flash);
158         if (!blk) {
159             break;
160         }
161         size = blk_getlength(blk);
162         if (size < 0) {
163             error_report("can't get size of block device %s: %s",
164                          blk_name(blk), strerror(-size));
165             exit(1);
166         }
167         if (size == 0 || !QEMU_IS_ALIGNED(size, FLASH_SECTOR_SIZE)) {
168             error_report("system firmware block device %s has invalid size "
169                          "%" PRId64,
170                          blk_name(blk), size);
171             info_report("its size must be a non-zero multiple of 0x%x",
172                         FLASH_SECTOR_SIZE);
173             exit(1);
174         }
175         if ((hwaddr)size != size
176             || total_size > HWADDR_MAX - size
177             || total_size + size > pcms->max_fw_size) {
178             error_report("combined size of system firmware exceeds "
179                          "%" PRIu64 " bytes",
180                          pcms->max_fw_size);
181             exit(1);
182         }
183 
184         total_size += size;
185         qdev_prop_set_uint32(DEVICE(system_flash), "num-blocks",
186                              size / FLASH_SECTOR_SIZE);
187         sysbus_realize_and_unref(SYS_BUS_DEVICE(system_flash), &error_fatal);
188         sysbus_mmio_map(SYS_BUS_DEVICE(system_flash), 0,
189                         0x100000000ULL - total_size);
190 
191         if (i == 0) {
192             flash_mem = pflash_cfi01_get_memory(system_flash);
193             pc_isa_bios_init(rom_memory, flash_mem, size);
194 
195             /* Encrypt the pflash boot ROM */
196             if (sev_enabled()) {
197                 flash_ptr = memory_region_get_ram_ptr(flash_mem);
198                 flash_size = memory_region_size(flash_mem);
199                 /*
200                  * OVMF places a GUIDed structures in the flash, so
201                  * search for them
202                  */
203                 pc_system_parse_ovmf_flash(flash_ptr, flash_size);
204 
205                 ret = sev_es_save_reset_vector(flash_ptr, flash_size);
206                 if (ret) {
207                     error_report("failed to locate and/or save reset vector");
208                     exit(1);
209                 }
210 
211                 sev_encrypt_flash(flash_ptr, flash_size, &error_fatal);
212             }
213         }
214     }
215 }
216 
217 void pc_system_firmware_init(PCMachineState *pcms,
218                              MemoryRegion *rom_memory)
219 {
220     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
221     int i;
222     BlockBackend *pflash_blk[ARRAY_SIZE(pcms->flash)];
223 
224     if (!pcmc->pci_enabled) {
225         x86_bios_rom_init(MACHINE(pcms), "bios.bin", rom_memory, true);
226         return;
227     }
228 
229     /* Map legacy -drive if=pflash to machine properties */
230     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
231         pflash_cfi01_legacy_drive(pcms->flash[i],
232                                   drive_get(IF_PFLASH, 0, i));
233         pflash_blk[i] = pflash_cfi01_get_blk(pcms->flash[i]);
234     }
235 
236     /* Reject gaps */
237     for (i = 1; i < ARRAY_SIZE(pcms->flash); i++) {
238         if (pflash_blk[i] && !pflash_blk[i - 1]) {
239             error_report("pflash%d requires pflash%d", i, i - 1);
240             exit(1);
241         }
242     }
243 
244     if (!pflash_blk[0]) {
245         /* Machine property pflash0 not set, use ROM mode */
246         x86_bios_rom_init(MACHINE(pcms), "bios.bin", rom_memory, false);
247     } else {
248         if (kvm_enabled() && !kvm_readonly_mem_enabled()) {
249             /*
250              * Older KVM cannot execute from device memory. So, flash
251              * memory cannot be used unless the readonly memory kvm
252              * capability is present.
253              */
254             error_report("pflash with kvm requires KVM readonly memory support");
255             exit(1);
256         }
257 
258         pc_system_flash_map(pcms, rom_memory);
259     }
260 
261     pc_system_flash_cleanup_unused(pcms);
262 }
263