xref: /openbmc/qemu/hw/riscv/boot.c (revision 33a9a57d)
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 "hw/riscv/boot_opensbi.h"
29 #include "elf.h"
30 #include "sysemu/device_tree.h"
31 #include "sysemu/qtest.h"
32 
33 #include <libfdt.h>
34 
35 #if defined(TARGET_RISCV32)
36 #define fw_dynamic_info_data(__val)     cpu_to_le32(__val)
37 #else
38 #define fw_dynamic_info_data(__val)     cpu_to_le64(__val)
39 #endif
40 
41 bool riscv_is_32_bit(MachineState *machine)
42 {
43     if (!strncmp(machine->cpu_type, "rv32", 4)) {
44         return true;
45     } else {
46         return false;
47     }
48 }
49 
50 target_ulong riscv_calc_kernel_start_addr(MachineState *machine,
51                                           target_ulong firmware_end_addr) {
52     if (riscv_is_32_bit(machine)) {
53         return QEMU_ALIGN_UP(firmware_end_addr, 4 * MiB);
54     } else {
55         return QEMU_ALIGN_UP(firmware_end_addr, 2 * MiB);
56     }
57 }
58 
59 target_ulong riscv_find_and_load_firmware(MachineState *machine,
60                                           const char *default_machine_firmware,
61                                           hwaddr firmware_load_addr,
62                                           symbol_fn_t sym_cb)
63 {
64     char *firmware_filename = NULL;
65     target_ulong firmware_end_addr = firmware_load_addr;
66 
67     if ((!machine->firmware) || (!strcmp(machine->firmware, "default"))) {
68         /*
69          * The user didn't specify -bios, or has specified "-bios default".
70          * That means we are going to load the OpenSBI binary included in
71          * the QEMU source.
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         firmware_end_addr = riscv_load_firmware(firmware_filename,
81                                                 firmware_load_addr, sym_cb);
82         g_free(firmware_filename);
83     }
84 
85     return firmware_end_addr;
86 }
87 
88 char *riscv_find_firmware(const char *firmware_filename)
89 {
90     char *filename;
91 
92     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, firmware_filename);
93     if (filename == NULL) {
94         if (!qtest_enabled()) {
95             /*
96              * We only ship plain binary bios images in the QEMU source.
97              * With Spike machine that uses ELF images as the default bios,
98              * running QEMU test will complain hence let's suppress the error
99              * report for QEMU testing.
100              */
101             error_report("Unable to load the RISC-V firmware \"%s\"",
102                          firmware_filename);
103             exit(1);
104         }
105     }
106 
107     return filename;
108 }
109 
110 target_ulong riscv_load_firmware(const char *firmware_filename,
111                                  hwaddr firmware_load_addr,
112                                  symbol_fn_t sym_cb)
113 {
114     uint64_t firmware_entry, firmware_size, firmware_end;
115 
116     if (load_elf_ram_sym(firmware_filename, NULL, NULL, NULL,
117                          &firmware_entry, NULL, &firmware_end, NULL,
118                          0, EM_RISCV, 1, 0, NULL, true, sym_cb) > 0) {
119         return firmware_end;
120     }
121 
122     firmware_size = load_image_targphys_as(firmware_filename,
123                                            firmware_load_addr, ram_size, NULL);
124 
125     if (firmware_size > 0) {
126         return firmware_load_addr + firmware_size;
127     }
128 
129     error_report("could not load firmware '%s'", firmware_filename);
130     exit(1);
131 }
132 
133 target_ulong riscv_load_kernel(const char *kernel_filename,
134                                target_ulong kernel_start_addr,
135                                symbol_fn_t sym_cb)
136 {
137     uint64_t kernel_entry;
138 
139     if (load_elf_ram_sym(kernel_filename, NULL, NULL, NULL,
140                          &kernel_entry, NULL, NULL, NULL, 0,
141                          EM_RISCV, 1, 0, NULL, true, sym_cb) > 0) {
142         return kernel_entry;
143     }
144 
145     if (load_uimage_as(kernel_filename, &kernel_entry, NULL, NULL,
146                        NULL, NULL, NULL) > 0) {
147         return kernel_entry;
148     }
149 
150     if (load_image_targphys_as(kernel_filename, kernel_start_addr,
151                                ram_size, NULL) > 0) {
152         return kernel_start_addr;
153     }
154 
155     error_report("could not load kernel '%s'", kernel_filename);
156     exit(1);
157 }
158 
159 hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
160                          uint64_t kernel_entry, hwaddr *start)
161 {
162     int size;
163 
164     /*
165      * We want to put the initrd far enough into RAM that when the
166      * kernel is uncompressed it will not clobber the initrd. However
167      * on boards without much RAM we must ensure that we still leave
168      * enough room for a decent sized initrd, and on boards with large
169      * amounts of RAM we must avoid the initrd being so far up in RAM
170      * that it is outside lowmem and inaccessible to the kernel.
171      * So for boards with less  than 256MB of RAM we put the initrd
172      * halfway into RAM, and for boards with 256MB of RAM or more we put
173      * the initrd at 128MB.
174      */
175     *start = kernel_entry + MIN(mem_size / 2, 128 * MiB);
176 
177     size = load_ramdisk(filename, *start, mem_size - *start);
178     if (size == -1) {
179         size = load_image_targphys(filename, *start, mem_size - *start);
180         if (size == -1) {
181             error_report("could not load ramdisk '%s'", filename);
182             exit(1);
183         }
184     }
185 
186     return *start + size;
187 }
188 
189 uint32_t riscv_load_fdt(hwaddr dram_base, uint64_t mem_size, void *fdt)
190 {
191     uint32_t temp, fdt_addr;
192     hwaddr dram_end = dram_base + mem_size;
193     int fdtsize = fdt_totalsize(fdt);
194 
195     if (fdtsize <= 0) {
196         error_report("invalid device-tree");
197         exit(1);
198     }
199 
200     /*
201      * We should put fdt as far as possible to avoid kernel/initrd overwriting
202      * its content. But it should be addressable by 32 bit system as well.
203      * Thus, put it at an aligned address that less than fdt size from end of
204      * dram or 4GB whichever is lesser.
205      */
206     temp = MIN(dram_end, 4096 * MiB);
207     fdt_addr = QEMU_ALIGN_DOWN(temp - fdtsize, 2 * MiB);
208 
209     fdt_pack(fdt);
210     /* copy in the device tree */
211     qemu_fdt_dumpdtb(fdt, fdtsize);
212 
213     rom_add_blob_fixed_as("fdt", fdt, fdtsize, fdt_addr,
214                           &address_space_memory);
215 
216     return fdt_addr;
217 }
218 
219 void riscv_rom_copy_firmware_info(hwaddr rom_base, hwaddr rom_size,
220                               uint32_t reset_vec_size, uint64_t kernel_entry)
221 {
222     struct fw_dynamic_info dinfo;
223     size_t dinfo_len;
224 
225     dinfo.magic = fw_dynamic_info_data(FW_DYNAMIC_INFO_MAGIC_VALUE);
226     dinfo.version = fw_dynamic_info_data(FW_DYNAMIC_INFO_VERSION);
227     dinfo.next_mode = fw_dynamic_info_data(FW_DYNAMIC_INFO_NEXT_MODE_S);
228     dinfo.next_addr = fw_dynamic_info_data(kernel_entry);
229     dinfo.options = 0;
230     dinfo.boot_hart = 0;
231     dinfo_len = sizeof(dinfo);
232 
233     /**
234      * copy the dynamic firmware info. This information is specific to
235      * OpenSBI but doesn't break any other firmware as long as they don't
236      * expect any certain value in "a2" register.
237      */
238     if (dinfo_len > (rom_size - reset_vec_size)) {
239         error_report("not enough space to store dynamic firmware info");
240         exit(1);
241     }
242 
243     rom_add_blob_fixed_as("mrom.finfo", &dinfo, dinfo_len,
244                            rom_base + reset_vec_size,
245                            &address_space_memory);
246 }
247 
248 void riscv_setup_rom_reset_vec(hwaddr start_addr, hwaddr rom_base,
249                                hwaddr rom_size, uint64_t kernel_entry,
250                                uint32_t fdt_load_addr, void *fdt)
251 {
252     int i;
253     uint32_t start_addr_hi32 = 0x00000000;
254 
255     #if defined(TARGET_RISCV64)
256     start_addr_hi32 = start_addr >> 32;
257     #endif
258     /* reset vector */
259     uint32_t reset_vec[10] = {
260         0x00000297,                  /* 1:  auipc  t0, %pcrel_hi(fw_dyn) */
261         0x02828613,                  /*     addi   a2, t0, %pcrel_lo(1b) */
262         0xf1402573,                  /*     csrr   a0, mhartid  */
263 #if defined(TARGET_RISCV32)
264         0x0202a583,                  /*     lw     a1, 32(t0) */
265         0x0182a283,                  /*     lw     t0, 24(t0) */
266 #elif defined(TARGET_RISCV64)
267         0x0202b583,                  /*     ld     a1, 32(t0) */
268         0x0182b283,                  /*     ld     t0, 24(t0) */
269 #endif
270         0x00028067,                  /*     jr     t0 */
271         start_addr,                  /* start: .dword */
272         start_addr_hi32,
273         fdt_load_addr,               /* fdt_laddr: .dword */
274         0x00000000,
275                                      /* fw_dyn: */
276     };
277 
278     /* copy in the reset vector in little_endian byte order */
279     for (i = 0; i < ARRAY_SIZE(reset_vec); i++) {
280         reset_vec[i] = cpu_to_le32(reset_vec[i]);
281     }
282     rom_add_blob_fixed_as("mrom.reset", reset_vec, sizeof(reset_vec),
283                           rom_base, &address_space_memory);
284     riscv_rom_copy_firmware_info(rom_base, rom_size, sizeof(reset_vec),
285                                  kernel_entry);
286 
287     return;
288 }
289