xref: /openbmc/qemu/hw/riscv/boot.c (revision 0c4e9931)
1 /*
2  * QEMU RISC-V Boot Helper
3  *
4  * Copyright (c) 2017 SiFive, Inc.
5  * Copyright (c) 2019 Alistair Francis <alistair.francis@wdc.com>
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2 or later, as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qemu-common.h"
22 #include "qemu/units.h"
23 #include "qemu/error-report.h"
24 #include "exec/cpu-defs.h"
25 #include "hw/boards.h"
26 #include "hw/loader.h"
27 #include "hw/riscv/boot.h"
28 #include "elf.h"
29 #include "sysemu/qtest.h"
30 
31 #if defined(TARGET_RISCV32)
32 # define KERNEL_BOOT_ADDRESS 0x80400000
33 #else
34 # define KERNEL_BOOT_ADDRESS 0x80200000
35 #endif
36 
37 void riscv_find_and_load_firmware(MachineState *machine,
38                                   const char *default_machine_firmware,
39                                   hwaddr firmware_load_addr,
40                                   symbol_fn_t sym_cb)
41 {
42     char *firmware_filename = NULL;
43 
44     if (!machine->firmware) {
45         /*
46          * The user didn't specify -bios.
47          * At the moment we default to loading nothing when this hapens.
48          * In the future this defaul will change to loading the prebuilt
49          * OpenSBI firmware. Let's warn the user and then continue.
50         */
51         if (!qtest_enabled()) {
52             warn_report("No -bios option specified. Not loading a firmware.");
53             warn_report("This default will change in a future QEMU release. " \
54                         "Please use the -bios option to avoid breakages when "\
55                         "this happens.");
56             warn_report("See QEMU's deprecation documentation for details.");
57         }
58         return;
59     }
60 
61     if (!strcmp(machine->firmware, "default")) {
62         /*
63          * The user has specified "-bios default". That means we are going to
64          * load the OpenSBI binary included in the QEMU source.
65          *
66          * We can't load the binary by default as it will break existing users
67          * as users are already loading their own firmware.
68          *
69          * Let's try to get everyone to specify the -bios option at all times,
70          * so then in the future we can make "-bios default" the default option
71          * if no -bios option is set without breaking anything.
72          */
73         firmware_filename = riscv_find_firmware(default_machine_firmware);
74     } else if (strcmp(machine->firmware, "none")) {
75         firmware_filename = riscv_find_firmware(machine->firmware);
76     }
77 
78     if (firmware_filename) {
79         /* If not "none" load the firmware */
80         riscv_load_firmware(firmware_filename, firmware_load_addr, sym_cb);
81         g_free(firmware_filename);
82     }
83 }
84 
85 char *riscv_find_firmware(const char *firmware_filename)
86 {
87     char *filename;
88 
89     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, firmware_filename);
90     if (filename == NULL) {
91         error_report("Unable to load the RISC-V firmware \"%s\"",
92                      firmware_filename);
93         exit(1);
94     }
95 
96     return filename;
97 }
98 
99 target_ulong riscv_load_firmware(const char *firmware_filename,
100                                  hwaddr firmware_load_addr,
101                                  symbol_fn_t sym_cb)
102 {
103     uint64_t firmware_entry, firmware_start, firmware_end;
104 
105     if (load_elf_ram_sym(firmware_filename, NULL, NULL, NULL,
106                          &firmware_entry, &firmware_start, &firmware_end, NULL,
107                          0, EM_RISCV, 1, 0, NULL, true, sym_cb) > 0) {
108         return firmware_entry;
109     }
110 
111     if (load_image_targphys_as(firmware_filename, firmware_load_addr,
112                                ram_size, NULL) > 0) {
113         return firmware_load_addr;
114     }
115 
116     error_report("could not load firmware '%s'", firmware_filename);
117     exit(1);
118 }
119 
120 target_ulong riscv_load_kernel(const char *kernel_filename, symbol_fn_t sym_cb)
121 {
122     uint64_t kernel_entry, kernel_high;
123 
124     if (load_elf_ram_sym(kernel_filename, NULL, NULL, NULL,
125                          &kernel_entry, NULL, &kernel_high, NULL, 0,
126                          EM_RISCV, 1, 0, NULL, true, sym_cb) > 0) {
127         return kernel_entry;
128     }
129 
130     if (load_uimage_as(kernel_filename, &kernel_entry, NULL, NULL,
131                        NULL, NULL, NULL) > 0) {
132         return kernel_entry;
133     }
134 
135     if (load_image_targphys_as(kernel_filename, KERNEL_BOOT_ADDRESS,
136                                ram_size, NULL) > 0) {
137         return KERNEL_BOOT_ADDRESS;
138     }
139 
140     error_report("could not load kernel '%s'", kernel_filename);
141     exit(1);
142 }
143 
144 hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
145                          uint64_t kernel_entry, hwaddr *start)
146 {
147     int size;
148 
149     /*
150      * We want to put the initrd far enough into RAM that when the
151      * kernel is uncompressed it will not clobber the initrd. However
152      * on boards without much RAM we must ensure that we still leave
153      * enough room for a decent sized initrd, and on boards with large
154      * amounts of RAM we must avoid the initrd being so far up in RAM
155      * that it is outside lowmem and inaccessible to the kernel.
156      * So for boards with less  than 256MB of RAM we put the initrd
157      * halfway into RAM, and for boards with 256MB of RAM or more we put
158      * the initrd at 128MB.
159      */
160     *start = kernel_entry + MIN(mem_size / 2, 128 * MiB);
161 
162     size = load_ramdisk(filename, *start, mem_size - *start);
163     if (size == -1) {
164         size = load_image_targphys(filename, *start, mem_size - *start);
165         if (size == -1) {
166             error_report("could not load ramdisk '%s'", filename);
167             exit(1);
168         }
169     }
170 
171     return *start + size;
172 }
173