xref: /openbmc/qemu/hw/i386/pc_sysfw.c (revision 9e6190ae)
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 {
46     int isa_bios_size;
47     MemoryRegion *isa_bios;
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     isa_bios = g_malloc(sizeof(*isa_bios));
56     memory_region_init_ram(isa_bios, NULL, "isa-bios", isa_bios_size,
57                            &error_fatal);
58     memory_region_add_subregion_overlap(rom_memory,
59                                         0x100000 - isa_bios_size,
60                                         isa_bios,
61                                         1);
62 
63     /* copy ISA rom image from top of flash memory */
64     flash_ptr = memory_region_get_ram_ptr(flash_mem);
65     isa_bios_ptr = memory_region_get_ram_ptr(isa_bios);
66     memcpy(isa_bios_ptr,
67            ((uint8_t*)flash_ptr) + (flash_size - isa_bios_size),
68            isa_bios_size);
69 
70     memory_region_set_readonly(isa_bios, true);
71 }
72 
73 static PFlashCFI01 *pc_pflash_create(PCMachineState *pcms,
74                                      const char *name,
75                                      const char *alias_prop_name)
76 {
77     DeviceState *dev = qdev_new(TYPE_PFLASH_CFI01);
78 
79     qdev_prop_set_uint64(dev, "sector-length", FLASH_SECTOR_SIZE);
80     qdev_prop_set_uint8(dev, "width", 1);
81     qdev_prop_set_string(dev, "name", name);
82     object_property_add_child(OBJECT(pcms), name, OBJECT(dev));
83     object_property_add_alias(OBJECT(pcms), alias_prop_name,
84                               OBJECT(dev), "drive");
85     /*
86      * The returned reference is tied to the child property and
87      * will be removed with object_unparent.
88      */
89     object_unref(OBJECT(dev));
90     return PFLASH_CFI01(dev);
91 }
92 
93 void pc_system_flash_create(PCMachineState *pcms)
94 {
95     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
96 
97     if (pcmc->pci_enabled) {
98         pcms->flash[0] = pc_pflash_create(pcms, "system.flash0",
99                                           "pflash0");
100         pcms->flash[1] = pc_pflash_create(pcms, "system.flash1",
101                                           "pflash1");
102     }
103 }
104 
105 void pc_system_flash_cleanup_unused(PCMachineState *pcms)
106 {
107     char *prop_name;
108     int i;
109 
110     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
111 
112     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
113         if (!qdev_is_realized(DEVICE(pcms->flash[i]))) {
114             prop_name = g_strdup_printf("pflash%d", i);
115             object_property_del(OBJECT(pcms), prop_name);
116             g_free(prop_name);
117             object_unparent(OBJECT(pcms->flash[i]));
118             pcms->flash[i] = NULL;
119         }
120     }
121 }
122 
123 /*
124  * Map the pcms->flash[] from 4GiB downward, and realize.
125  * Map them in descending order, i.e. pcms->flash[0] at the top,
126  * without gaps.
127  * Stop at the first pcms->flash[0] lacking a block backend.
128  * Set each flash's size from its block backend.  Fatal error if the
129  * size isn't a non-zero multiple of 4KiB, or the total size exceeds
130  * pcms->max_fw_size.
131  *
132  * If pcms->flash[0] has a block backend, its memory is passed to
133  * pc_isa_bios_init().  Merging several flash devices for isa-bios is
134  * not supported.
135  */
136 static void pc_system_flash_map(PCMachineState *pcms,
137                                 MemoryRegion *rom_memory)
138 {
139     hwaddr total_size = 0;
140     int i;
141     BlockBackend *blk;
142     int64_t size;
143     PFlashCFI01 *system_flash;
144     MemoryRegion *flash_mem;
145     void *flash_ptr;
146     int flash_size;
147 
148     assert(PC_MACHINE_GET_CLASS(pcms)->pci_enabled);
149 
150     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
151         system_flash = pcms->flash[i];
152         blk = pflash_cfi01_get_blk(system_flash);
153         if (!blk) {
154             break;
155         }
156         size = blk_getlength(blk);
157         if (size < 0) {
158             error_report("can't get size of block device %s: %s",
159                          blk_name(blk), strerror(-size));
160             exit(1);
161         }
162         if (size == 0 || !QEMU_IS_ALIGNED(size, FLASH_SECTOR_SIZE)) {
163             error_report("system firmware block device %s has invalid size "
164                          "%" PRId64,
165                          blk_name(blk), size);
166             info_report("its size must be a non-zero multiple of 0x%x",
167                         FLASH_SECTOR_SIZE);
168             exit(1);
169         }
170         if ((hwaddr)size != size
171             || total_size > HWADDR_MAX - size
172             || total_size + size > pcms->max_fw_size) {
173             error_report("combined size of system firmware exceeds "
174                          "%" PRIu64 " bytes",
175                          pcms->max_fw_size);
176             exit(1);
177         }
178 
179         total_size += size;
180         qdev_prop_set_uint32(DEVICE(system_flash), "num-blocks",
181                              size / FLASH_SECTOR_SIZE);
182         sysbus_realize_and_unref(SYS_BUS_DEVICE(system_flash), &error_fatal);
183         sysbus_mmio_map(SYS_BUS_DEVICE(system_flash), 0,
184                         0x100000000ULL - total_size);
185 
186         if (i == 0) {
187             flash_mem = pflash_cfi01_get_memory(system_flash);
188             pc_isa_bios_init(rom_memory, flash_mem);
189 
190             /* Encrypt the pflash boot ROM */
191             if (sev_enabled()) {
192                 flash_ptr = memory_region_get_ram_ptr(flash_mem);
193                 flash_size = memory_region_size(flash_mem);
194                 x86_firmware_configure(flash_ptr, flash_size);
195             }
196         }
197     }
198 }
199 
200 void pc_system_firmware_init(PCMachineState *pcms,
201                              MemoryRegion *rom_memory)
202 {
203     PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
204     int i;
205     BlockBackend *pflash_blk[ARRAY_SIZE(pcms->flash)];
206 
207     if (!pcmc->pci_enabled) {
208         x86_bios_rom_init(MACHINE(pcms), "bios.bin", rom_memory, true);
209         return;
210     }
211 
212     /* Map legacy -drive if=pflash to machine properties */
213     for (i = 0; i < ARRAY_SIZE(pcms->flash); i++) {
214         pflash_cfi01_legacy_drive(pcms->flash[i],
215                                   drive_get(IF_PFLASH, 0, i));
216         pflash_blk[i] = pflash_cfi01_get_blk(pcms->flash[i]);
217     }
218 
219     /* Reject gaps */
220     for (i = 1; i < ARRAY_SIZE(pcms->flash); i++) {
221         if (pflash_blk[i] && !pflash_blk[i - 1]) {
222             error_report("pflash%d requires pflash%d", i, i - 1);
223             exit(1);
224         }
225     }
226 
227     if (!pflash_blk[0]) {
228         /* Machine property pflash0 not set, use ROM mode */
229         x86_bios_rom_init(MACHINE(pcms), "bios.bin", rom_memory, false);
230     } else {
231         if (kvm_enabled() && !kvm_readonly_mem_enabled()) {
232             /*
233              * Older KVM cannot execute from device memory. So, flash
234              * memory cannot be used unless the readonly memory kvm
235              * capability is present.
236              */
237             error_report("pflash with kvm requires KVM readonly memory support");
238             exit(1);
239         }
240 
241         pc_system_flash_map(pcms, rom_memory);
242     }
243 
244     pc_system_flash_cleanup_unused(pcms);
245 }
246 
247 void x86_firmware_configure(void *ptr, int size)
248 {
249     int ret;
250 
251     /*
252      * OVMF places a GUIDed structures in the flash, so
253      * search for them
254      */
255     pc_system_parse_ovmf_flash(ptr, size);
256 
257     if (sev_enabled()) {
258         ret = sev_es_save_reset_vector(ptr, size);
259         if (ret) {
260             error_report("failed to locate and/or save reset vector");
261             exit(1);
262         }
263 
264         sev_encrypt_flash(ptr, size, &error_fatal);
265     }
266 }
267