xref: /openbmc/qemu/hw/i386/pc_sysfw.c (revision 228aa992)
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 "sysemu/block-backend.h"
27 #include "qemu/error-report.h"
28 #include "hw/sysbus.h"
29 #include "hw/hw.h"
30 #include "hw/i386/pc.h"
31 #include "hw/boards.h"
32 #include "hw/loader.h"
33 #include "sysemu/sysemu.h"
34 #include "hw/block/flash.h"
35 #include "sysemu/kvm.h"
36 
37 #define BIOS_FILENAME "bios.bin"
38 
39 typedef struct PcSysFwDevice {
40     SysBusDevice busdev;
41     uint8_t isapc_ram_fw;
42 } PcSysFwDevice;
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 * 1024);
57     isa_bios = g_malloc(sizeof(*isa_bios));
58     memory_region_init_ram(isa_bios, NULL, "isa-bios", isa_bios_size,
59                            &error_abort);
60     vmstate_register_ram_global(isa_bios);
61     memory_region_add_subregion_overlap(rom_memory,
62                                         0x100000 - isa_bios_size,
63                                         isa_bios,
64                                         1);
65 
66     /* copy ISA rom image from top of flash memory */
67     flash_ptr = memory_region_get_ram_ptr(flash_mem);
68     isa_bios_ptr = memory_region_get_ram_ptr(isa_bios);
69     memcpy(isa_bios_ptr,
70            ((uint8_t*)flash_ptr) + (flash_size - isa_bios_size),
71            isa_bios_size);
72 
73     memory_region_set_readonly(isa_bios, true);
74 }
75 
76 #define FLASH_MAP_UNIT_MAX 2
77 
78 /* We don't have a theoretically justifiable exact lower bound on the base
79  * address of any flash mapping. In practice, the IO-APIC MMIO range is
80  * [0xFEE00000..0xFEE01000[ -- see IO_APIC_DEFAULT_ADDRESS --, leaving free
81  * only 18MB-4KB below 4G. For now, restrict the cumulative mapping to 8MB in
82  * size.
83  */
84 #define FLASH_MAP_BASE_MIN ((hwaddr)(0x100000000ULL - 8*1024*1024))
85 
86 /* This function maps flash drives from 4G downward, in order of their unit
87  * numbers. The mapping starts at unit#0, with unit number increments of 1, and
88  * stops before the first missing flash drive, or before
89  * unit#FLASH_MAP_UNIT_MAX, whichever is reached first.
90  *
91  * Addressing within one flash drive is of course not reversed.
92  *
93  * An error message is printed and the process exits if:
94  * - the size of the backing file for a flash drive is non-positive, or not a
95  *   multiple of the required sector size, or
96  * - the current mapping's base address would fall below FLASH_MAP_BASE_MIN.
97  *
98  * The drive with unit#0 (if available) is mapped at the highest address, and
99  * it is passed to pc_isa_bios_init(). Merging several drives for isa-bios is
100  * not supported.
101  */
102 static void pc_system_flash_init(MemoryRegion *rom_memory)
103 {
104     int unit;
105     DriveInfo *pflash_drv;
106     BlockBackend *blk;
107     int64_t size;
108     char *fatal_errmsg = NULL;
109     hwaddr phys_addr = 0x100000000ULL;
110     int sector_bits, sector_size;
111     pflash_t *system_flash;
112     MemoryRegion *flash_mem;
113     char name[64];
114 
115     sector_bits = 12;
116     sector_size = 1 << sector_bits;
117 
118     for (unit = 0;
119          (unit < FLASH_MAP_UNIT_MAX &&
120           (pflash_drv = drive_get(IF_PFLASH, 0, unit)) != NULL);
121          ++unit) {
122         blk = blk_by_legacy_dinfo(pflash_drv);
123         size = blk_getlength(blk);
124         if (size < 0) {
125             fatal_errmsg = g_strdup_printf("failed to get backing file size");
126         } else if (size == 0) {
127             fatal_errmsg = g_strdup_printf("PC system firmware (pflash) "
128                                "cannot have zero size");
129         } else if ((size % sector_size) != 0) {
130             fatal_errmsg = g_strdup_printf("PC system firmware (pflash) "
131                                "must be a multiple of 0x%x", sector_size);
132         } else if (phys_addr < size || phys_addr - size < FLASH_MAP_BASE_MIN) {
133             fatal_errmsg = g_strdup_printf("oversized backing file, pflash "
134                                "segments cannot be mapped under "
135                                TARGET_FMT_plx, FLASH_MAP_BASE_MIN);
136         }
137         if (fatal_errmsg != NULL) {
138             Location loc;
139 
140             /* push a new, "none" location on the location stack; overwrite its
141              * contents with the location saved in the option; print the error
142              * (includes location); pop the top
143              */
144             loc_push_none(&loc);
145             if (pflash_drv->opts != NULL) {
146                 qemu_opts_loc_restore(pflash_drv->opts);
147             }
148             error_report("%s", fatal_errmsg);
149             loc_pop(&loc);
150             g_free(fatal_errmsg);
151             exit(1);
152         }
153 
154         phys_addr -= size;
155 
156         /* pflash_cfi01_register() creates a deep copy of the name */
157         snprintf(name, sizeof name, "system.flash%d", unit);
158         system_flash = pflash_cfi01_register(phys_addr, NULL /* qdev */, name,
159                                              size, blk, sector_size,
160                                              size >> sector_bits,
161                                              1      /* width */,
162                                              0x0000 /* id0 */,
163                                              0x0000 /* id1 */,
164                                              0x0000 /* id2 */,
165                                              0x0000 /* id3 */,
166                                              0      /* be */);
167         if (unit == 0) {
168             flash_mem = pflash_cfi01_get_memory(system_flash);
169             pc_isa_bios_init(rom_memory, flash_mem, size);
170         }
171     }
172 }
173 
174 static void old_pc_system_rom_init(MemoryRegion *rom_memory, bool isapc_ram_fw)
175 {
176     char *filename;
177     MemoryRegion *bios, *isa_bios;
178     int bios_size, isa_bios_size;
179     int ret;
180 
181     /* BIOS load */
182     if (bios_name == NULL) {
183         bios_name = BIOS_FILENAME;
184     }
185     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
186     if (filename) {
187         bios_size = get_image_size(filename);
188     } else {
189         bios_size = -1;
190     }
191     if (bios_size <= 0 ||
192         (bios_size % 65536) != 0) {
193         goto bios_error;
194     }
195     bios = g_malloc(sizeof(*bios));
196     memory_region_init_ram(bios, NULL, "pc.bios", bios_size, &error_abort);
197     vmstate_register_ram_global(bios);
198     if (!isapc_ram_fw) {
199         memory_region_set_readonly(bios, true);
200     }
201     ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
202     if (ret != 0) {
203     bios_error:
204         fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
205         exit(1);
206     }
207     if (filename) {
208         g_free(filename);
209     }
210 
211     /* map the last 128KB of the BIOS in ISA space */
212     isa_bios_size = bios_size;
213     if (isa_bios_size > (128 * 1024)) {
214         isa_bios_size = 128 * 1024;
215     }
216     isa_bios = g_malloc(sizeof(*isa_bios));
217     memory_region_init_alias(isa_bios, NULL, "isa-bios", bios,
218                              bios_size - isa_bios_size, isa_bios_size);
219     memory_region_add_subregion_overlap(rom_memory,
220                                         0x100000 - isa_bios_size,
221                                         isa_bios,
222                                         1);
223     if (!isapc_ram_fw) {
224         memory_region_set_readonly(isa_bios, true);
225     }
226 
227     /* map all the bios at the top of memory */
228     memory_region_add_subregion(rom_memory,
229                                 (uint32_t)(-bios_size),
230                                 bios);
231 }
232 
233 void pc_system_firmware_init(MemoryRegion *rom_memory, bool isapc_ram_fw)
234 {
235     DriveInfo *pflash_drv;
236 
237     pflash_drv = drive_get(IF_PFLASH, 0, 0);
238 
239     if (isapc_ram_fw || pflash_drv == NULL) {
240         /* When a pflash drive is not found, use rom-mode */
241         old_pc_system_rom_init(rom_memory, isapc_ram_fw);
242         return;
243     }
244 
245     if (kvm_enabled() && !kvm_readonly_mem_enabled()) {
246         /* Older KVM cannot execute from device memory. So, flash memory
247          * cannot be used unless the readonly memory kvm capability is present. */
248         fprintf(stderr, "qemu: pflash with kvm requires KVM readonly memory support\n");
249         exit(1);
250     }
251 
252     pc_system_flash_init(rom_memory);
253 }
254