xref: /openbmc/qemu/hw/i386/pc_sysfw.c (revision d6032e06)
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/blockdev.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     vmstate_register_ram_global(isa_bios);
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 #define FLASH_MAP_UNIT_MAX 2
76 
77 /* We don't have a theoretically justifiable exact lower bound on the base
78  * address of any flash mapping. In practice, the IO-APIC MMIO range is
79  * [0xFEE00000..0xFEE01000[ -- see IO_APIC_DEFAULT_ADDRESS --, leaving free
80  * only 18MB-4KB below 4G. For now, restrict the cumulative mapping to 8MB in
81  * size.
82  */
83 #define FLASH_MAP_BASE_MIN ((hwaddr)(0x100000000ULL - 8*1024*1024))
84 
85 /* This function maps flash drives from 4G downward, in order of their unit
86  * numbers. The mapping starts at unit#0, with unit number increments of 1, and
87  * stops before the first missing flash drive, or before
88  * unit#FLASH_MAP_UNIT_MAX, whichever is reached first.
89  *
90  * Addressing within one flash drive is of course not reversed.
91  *
92  * An error message is printed and the process exits if:
93  * - the size of the backing file for a flash drive is non-positive, or not a
94  *   multiple of the required sector size, or
95  * - the current mapping's base address would fall below FLASH_MAP_BASE_MIN.
96  *
97  * The drive with unit#0 (if available) is mapped at the highest address, and
98  * it is passed to pc_isa_bios_init(). Merging several drives for isa-bios is
99  * not supported.
100  */
101 static void pc_system_flash_init(MemoryRegion *rom_memory)
102 {
103     int unit;
104     DriveInfo *pflash_drv;
105     BlockDriverState *bdrv;
106     int64_t size;
107     char *fatal_errmsg = NULL;
108     hwaddr phys_addr = 0x100000000ULL;
109     int sector_bits, sector_size;
110     pflash_t *system_flash;
111     MemoryRegion *flash_mem;
112     char name[64];
113 
114     sector_bits = 12;
115     sector_size = 1 << sector_bits;
116 
117     for (unit = 0;
118          (unit < FLASH_MAP_UNIT_MAX &&
119           (pflash_drv = drive_get(IF_PFLASH, 0, unit)) != NULL);
120          ++unit) {
121         bdrv = pflash_drv->bdrv;
122         size = bdrv_getlength(bdrv);
123         if (size < 0) {
124             fatal_errmsg = g_strdup_printf("failed to get backing file size");
125         } else if (size == 0) {
126             fatal_errmsg = g_strdup_printf("PC system firmware (pflash) "
127                                "cannot have zero size");
128         } else if ((size % sector_size) != 0) {
129             fatal_errmsg = g_strdup_printf("PC system firmware (pflash) "
130                                "must be a multiple of 0x%x", sector_size);
131         } else if (phys_addr < size || phys_addr - size < FLASH_MAP_BASE_MIN) {
132             fatal_errmsg = g_strdup_printf("oversized backing file, pflash "
133                                "segments cannot be mapped under "
134                                TARGET_FMT_plx, FLASH_MAP_BASE_MIN);
135         }
136         if (fatal_errmsg != NULL) {
137             Location loc;
138 
139             /* push a new, "none" location on the location stack; overwrite its
140              * contents with the location saved in the option; print the error
141              * (includes location); pop the top
142              */
143             loc_push_none(&loc);
144             if (pflash_drv->opts != NULL) {
145                 qemu_opts_loc_restore(pflash_drv->opts);
146             }
147             error_report("%s", fatal_errmsg);
148             loc_pop(&loc);
149             g_free(fatal_errmsg);
150             exit(1);
151         }
152 
153         phys_addr -= size;
154 
155         /* pflash_cfi01_register() creates a deep copy of the name */
156         snprintf(name, sizeof name, "system.flash%d", unit);
157         system_flash = pflash_cfi01_register(phys_addr, NULL /* qdev */, name,
158                                              size, bdrv, sector_size,
159                                              size >> sector_bits,
160                                              1      /* width */,
161                                              0x0000 /* id0 */,
162                                              0x0000 /* id1 */,
163                                              0x0000 /* id2 */,
164                                              0x0000 /* id3 */,
165                                              0      /* be */);
166         if (unit == 0) {
167             flash_mem = pflash_cfi01_get_memory(system_flash);
168             pc_isa_bios_init(rom_memory, flash_mem, size);
169         }
170     }
171 }
172 
173 static void old_pc_system_rom_init(MemoryRegion *rom_memory, bool isapc_ram_fw)
174 {
175     char *filename;
176     MemoryRegion *bios, *isa_bios;
177     int bios_size, isa_bios_size;
178     int ret;
179 
180     /* BIOS load */
181     if (bios_name == NULL) {
182         bios_name = BIOS_FILENAME;
183     }
184     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
185     if (filename) {
186         bios_size = get_image_size(filename);
187     } else {
188         bios_size = -1;
189     }
190     if (bios_size <= 0 ||
191         (bios_size % 65536) != 0) {
192         goto bios_error;
193     }
194     bios = g_malloc(sizeof(*bios));
195     memory_region_init_ram(bios, NULL, "pc.bios", bios_size);
196     vmstate_register_ram_global(bios);
197     if (!isapc_ram_fw) {
198         memory_region_set_readonly(bios, true);
199     }
200     ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);
201     if (ret != 0) {
202     bios_error:
203         fprintf(stderr, "qemu: could not load PC BIOS '%s'\n", bios_name);
204         exit(1);
205     }
206     if (filename) {
207         g_free(filename);
208     }
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