xref: /openbmc/qemu/hw/i386/pc_sysfw.c (revision 9884abee)
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 "sysemu/block-backend.h"
28 #include "qemu/error-report.h"
29 #include "hw/sysbus.h"
30 #include "hw/hw.h"
31 #include "hw/i386/pc.h"
32 #include "hw/boards.h"
33 #include "hw/loader.h"
34 #include "sysemu/sysemu.h"
35 #include "hw/block/flash.h"
36 #include "sysemu/kvm.h"
37 
38 #define BIOS_FILENAME "bios.bin"
39 
40 typedef struct PcSysFwDevice {
41     SysBusDevice busdev;
42     uint8_t isapc_ram_fw;
43 } PcSysFwDevice;
44 
45 static void pc_isa_bios_init(MemoryRegion *rom_memory,
46                              MemoryRegion *flash_mem,
47                              int ram_size)
48 {
49     int isa_bios_size;
50     MemoryRegion *isa_bios;
51     uint64_t flash_size;
52     void *flash_ptr, *isa_bios_ptr;
53 
54     flash_size = memory_region_size(flash_mem);
55 
56     /* map the last 128KB of the BIOS in ISA space */
57     isa_bios_size = MIN(flash_size, 128 * 1024);
58     isa_bios = g_malloc(sizeof(*isa_bios));
59     memory_region_init_ram(isa_bios, NULL, "isa-bios", isa_bios_size,
60                            &error_fatal);
61     vmstate_register_ram_global(isa_bios);
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     memory_region_set_readonly(isa_bios, true);
75 }
76 
77 #define FLASH_MAP_UNIT_MAX 2
78 
79 /* We don't have a theoretically justifiable exact lower bound on the base
80  * address of any flash mapping. In practice, the IO-APIC MMIO range is
81  * [0xFEE00000..0xFEE01000[ -- see IO_APIC_DEFAULT_ADDRESS --, leaving free
82  * only 18MB-4KB below 4G. For now, restrict the cumulative mapping to 8MB in
83  * size.
84  */
85 #define FLASH_MAP_BASE_MIN ((hwaddr)(0x100000000ULL - 8*1024*1024))
86 
87 /* This function maps flash drives from 4G downward, in order of their unit
88  * numbers. The mapping starts at unit#0, with unit number increments of 1, and
89  * stops before the first missing flash drive, or before
90  * unit#FLASH_MAP_UNIT_MAX, whichever is reached first.
91  *
92  * Addressing within one flash drive is of course not reversed.
93  *
94  * An error message is printed and the process exits if:
95  * - the size of the backing file for a flash drive is non-positive, or not a
96  *   multiple of the required sector size, or
97  * - the current mapping's base address would fall below FLASH_MAP_BASE_MIN.
98  *
99  * The drive with unit#0 (if available) is mapped at the highest address, and
100  * it is passed to pc_isa_bios_init(). Merging several drives for isa-bios is
101  * not supported.
102  */
103 static void pc_system_flash_init(MemoryRegion *rom_memory)
104 {
105     int unit;
106     DriveInfo *pflash_drv;
107     BlockBackend *blk;
108     int64_t size;
109     char *fatal_errmsg = NULL;
110     hwaddr phys_addr = 0x100000000ULL;
111     int sector_bits, sector_size;
112     pflash_t *system_flash;
113     MemoryRegion *flash_mem;
114     char name[64];
115 
116     sector_bits = 12;
117     sector_size = 1 << sector_bits;
118 
119     for (unit = 0;
120          (unit < FLASH_MAP_UNIT_MAX &&
121           (pflash_drv = drive_get(IF_PFLASH, 0, unit)) != NULL);
122          ++unit) {
123         blk = blk_by_legacy_dinfo(pflash_drv);
124         size = blk_getlength(blk);
125         if (size < 0) {
126             fatal_errmsg = g_strdup_printf("failed to get backing file size");
127         } else if (size == 0) {
128             fatal_errmsg = g_strdup_printf("PC system firmware (pflash) "
129                                "cannot have zero size");
130         } else if ((size % sector_size) != 0) {
131             fatal_errmsg = g_strdup_printf("PC system firmware (pflash) "
132                                "must be a multiple of 0x%x", sector_size);
133         } else if (phys_addr < size || phys_addr - size < FLASH_MAP_BASE_MIN) {
134             fatal_errmsg = g_strdup_printf("oversized backing file, pflash "
135                                "segments cannot be mapped under "
136                                TARGET_FMT_plx, FLASH_MAP_BASE_MIN);
137         }
138         if (fatal_errmsg != NULL) {
139             Location loc;
140 
141             /* push a new, "none" location on the location stack; overwrite its
142              * contents with the location saved in the option; print the error
143              * (includes location); pop the top
144              */
145             loc_push_none(&loc);
146             if (pflash_drv->opts != NULL) {
147                 qemu_opts_loc_restore(pflash_drv->opts);
148             }
149             error_report("%s", fatal_errmsg);
150             loc_pop(&loc);
151             g_free(fatal_errmsg);
152             exit(1);
153         }
154 
155         phys_addr -= size;
156 
157         /* pflash_cfi01_register() creates a deep copy of the name */
158         snprintf(name, sizeof name, "system.flash%d", unit);
159         system_flash = pflash_cfi01_register(phys_addr, NULL /* qdev */, name,
160                                              size, blk, sector_size,
161                                              size >> sector_bits,
162                                              1      /* width */,
163                                              0x0000 /* id0 */,
164                                              0x0000 /* id1 */,
165                                              0x0000 /* id2 */,
166                                              0x0000 /* id3 */,
167                                              0      /* be */);
168         if (unit == 0) {
169             flash_mem = pflash_cfi01_get_memory(system_flash);
170             pc_isa_bios_init(rom_memory, flash_mem, size);
171         }
172     }
173 }
174 
175 static void old_pc_system_rom_init(MemoryRegion *rom_memory, bool isapc_ram_fw)
176 {
177     char *filename;
178     MemoryRegion *bios, *isa_bios;
179     int bios_size, isa_bios_size;
180     int ret;
181 
182     /* BIOS load */
183     if (bios_name == NULL) {
184         bios_name = BIOS_FILENAME;
185     }
186     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
187     if (filename) {
188         bios_size = get_image_size(filename);
189     } else {
190         bios_size = -1;
191     }
192     if (bios_size <= 0 ||
193         (bios_size % 65536) != 0) {
194         goto bios_error;
195     }
196     bios = g_malloc(sizeof(*bios));
197     memory_region_init_ram(bios, NULL, "pc.bios", bios_size, &error_fatal);
198     vmstate_register_ram_global(bios);
199     if (!isapc_ram_fw) {
200         memory_region_set_readonly(bios, true);
201     }
202     ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
203     if (ret != 0) {
204     bios_error:
205         fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
206         exit(1);
207     }
208     g_free(filename);
209 
210     /* map the last 128KB of the BIOS in ISA space */
211     isa_bios_size = bios_size;
212     if (isa_bios_size > (128 * 1024)) {
213         isa_bios_size = 128 * 1024;
214     }
215     isa_bios = g_malloc(sizeof(*isa_bios));
216     memory_region_init_alias(isa_bios, NULL, "isa-bios", bios,
217                              bios_size - isa_bios_size, isa_bios_size);
218     memory_region_add_subregion_overlap(rom_memory,
219                                         0x100000 - isa_bios_size,
220                                         isa_bios,
221                                         1);
222     if (!isapc_ram_fw) {
223         memory_region_set_readonly(isa_bios, true);
224     }
225 
226     /* map all the bios at the top of memory */
227     memory_region_add_subregion(rom_memory,
228                                 (uint32_t)(-bios_size),
229                                 bios);
230 }
231 
232 void pc_system_firmware_init(MemoryRegion *rom_memory, bool isapc_ram_fw)
233 {
234     DriveInfo *pflash_drv;
235 
236     pflash_drv = drive_get(IF_PFLASH, 0, 0);
237 
238     if (isapc_ram_fw || pflash_drv == NULL) {
239         /* When a pflash drive is not found, use rom-mode */
240         old_pc_system_rom_init(rom_memory, isapc_ram_fw);
241         return;
242     }
243 
244     if (kvm_enabled() && !kvm_readonly_mem_enabled()) {
245         /* Older KVM cannot execute from device memory. So, flash memory
246          * cannot be used unless the readonly memory kvm capability is present. */
247         fprintf(stderr, "qemu: pflash with kvm requires KVM readonly memory support\n");
248         exit(1);
249     }
250 
251     pc_system_flash_init(rom_memory);
252 }
253