xref: /openbmc/qemu/hw/riscv/boot.c (revision c63ca4ff)
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/datadir.h"
23 #include "qemu/units.h"
24 #include "qemu/error-report.h"
25 #include "exec/cpu-defs.h"
26 #include "hw/boards.h"
27 #include "hw/loader.h"
28 #include "hw/riscv/boot.h"
29 #include "hw/riscv/boot_opensbi.h"
30 #include "elf.h"
31 #include "sysemu/device_tree.h"
32 #include "sysemu/qtest.h"
33 
34 #include <libfdt.h>
35 
36 #if defined(TARGET_RISCV32)
37 #define fw_dynamic_info_data(__val)     cpu_to_le32(__val)
38 #else
39 #define fw_dynamic_info_data(__val)     cpu_to_le64(__val)
40 #endif
41 
42 bool riscv_is_32_bit(MachineState *machine)
43 {
44     if (!strncmp(machine->cpu_type, "rv32", 4)) {
45         return true;
46     } else {
47         return false;
48     }
49 }
50 
51 target_ulong riscv_calc_kernel_start_addr(MachineState *machine,
52                                           target_ulong firmware_end_addr) {
53     if (riscv_is_32_bit(machine)) {
54         return QEMU_ALIGN_UP(firmware_end_addr, 4 * MiB);
55     } else {
56         return QEMU_ALIGN_UP(firmware_end_addr, 2 * MiB);
57     }
58 }
59 
60 target_ulong riscv_find_and_load_firmware(MachineState *machine,
61                                           const char *default_machine_firmware,
62                                           hwaddr firmware_load_addr,
63                                           symbol_fn_t sym_cb)
64 {
65     char *firmware_filename = NULL;
66     target_ulong firmware_end_addr = firmware_load_addr;
67 
68     if ((!machine->firmware) || (!strcmp(machine->firmware, "default"))) {
69         /*
70          * The user didn't specify -bios, or has specified "-bios default".
71          * That means we are going to load the OpenSBI binary included in
72          * the QEMU source.
73          */
74         firmware_filename = riscv_find_firmware(default_machine_firmware);
75     } else if (strcmp(machine->firmware, "none")) {
76         firmware_filename = riscv_find_firmware(machine->firmware);
77     }
78 
79     if (firmware_filename) {
80         /* If not "none" load the firmware */
81         firmware_end_addr = riscv_load_firmware(firmware_filename,
82                                                 firmware_load_addr, sym_cb);
83         g_free(firmware_filename);
84     }
85 
86     return firmware_end_addr;
87 }
88 
89 char *riscv_find_firmware(const char *firmware_filename)
90 {
91     char *filename;
92 
93     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, firmware_filename);
94     if (filename == NULL) {
95         if (!qtest_enabled()) {
96             /*
97              * We only ship plain binary bios images in the QEMU source.
98              * With Spike machine that uses ELF images as the default bios,
99              * running QEMU test will complain hence let's suppress the error
100              * report for QEMU testing.
101              */
102             error_report("Unable to load the RISC-V firmware \"%s\"",
103                          firmware_filename);
104             exit(1);
105         }
106     }
107 
108     return filename;
109 }
110 
111 target_ulong riscv_load_firmware(const char *firmware_filename,
112                                  hwaddr firmware_load_addr,
113                                  symbol_fn_t sym_cb)
114 {
115     uint64_t firmware_entry, firmware_size, firmware_end;
116 
117     if (load_elf_ram_sym(firmware_filename, NULL, NULL, NULL,
118                          &firmware_entry, NULL, &firmware_end, NULL,
119                          0, EM_RISCV, 1, 0, NULL, true, sym_cb) > 0) {
120         return firmware_end;
121     }
122 
123     firmware_size = load_image_targphys_as(firmware_filename,
124                                            firmware_load_addr,
125                                            current_machine->ram_size, NULL);
126 
127     if (firmware_size > 0) {
128         return firmware_load_addr + firmware_size;
129     }
130 
131     error_report("could not load firmware '%s'", firmware_filename);
132     exit(1);
133 }
134 
135 target_ulong riscv_load_kernel(const char *kernel_filename,
136                                target_ulong kernel_start_addr,
137                                symbol_fn_t sym_cb)
138 {
139     uint64_t kernel_entry;
140 
141     if (load_elf_ram_sym(kernel_filename, NULL, NULL, NULL,
142                          &kernel_entry, NULL, NULL, NULL, 0,
143                          EM_RISCV, 1, 0, NULL, true, sym_cb) > 0) {
144         return kernel_entry;
145     }
146 
147     if (load_uimage_as(kernel_filename, &kernel_entry, NULL, NULL,
148                        NULL, NULL, NULL) > 0) {
149         return kernel_entry;
150     }
151 
152     if (load_image_targphys_as(kernel_filename, kernel_start_addr,
153                                current_machine->ram_size, NULL) > 0) {
154         return kernel_start_addr;
155     }
156 
157     error_report("could not load kernel '%s'", kernel_filename);
158     exit(1);
159 }
160 
161 hwaddr riscv_load_initrd(const char *filename, uint64_t mem_size,
162                          uint64_t kernel_entry, hwaddr *start)
163 {
164     int size;
165 
166     /*
167      * We want to put the initrd far enough into RAM that when the
168      * kernel is uncompressed it will not clobber the initrd. However
169      * on boards without much RAM we must ensure that we still leave
170      * enough room for a decent sized initrd, and on boards with large
171      * amounts of RAM we must avoid the initrd being so far up in RAM
172      * that it is outside lowmem and inaccessible to the kernel.
173      * So for boards with less  than 256MB of RAM we put the initrd
174      * halfway into RAM, and for boards with 256MB of RAM or more we put
175      * the initrd at 128MB.
176      */
177     *start = kernel_entry + MIN(mem_size / 2, 128 * MiB);
178 
179     size = load_ramdisk(filename, *start, mem_size - *start);
180     if (size == -1) {
181         size = load_image_targphys(filename, *start, mem_size - *start);
182         if (size == -1) {
183             error_report("could not load ramdisk '%s'", filename);
184             exit(1);
185         }
186     }
187 
188     return *start + size;
189 }
190 
191 uint32_t riscv_load_fdt(hwaddr dram_base, uint64_t mem_size, void *fdt)
192 {
193     uint32_t temp, fdt_addr;
194     hwaddr dram_end = dram_base + mem_size;
195     int fdtsize = fdt_totalsize(fdt);
196 
197     if (fdtsize <= 0) {
198         error_report("invalid device-tree");
199         exit(1);
200     }
201 
202     /*
203      * We should put fdt as far as possible to avoid kernel/initrd overwriting
204      * its content. But it should be addressable by 32 bit system as well.
205      * Thus, put it at an aligned address that less than fdt size from end of
206      * dram or 4GB whichever is lesser.
207      */
208     temp = MIN(dram_end, 4096 * MiB);
209     fdt_addr = QEMU_ALIGN_DOWN(temp - fdtsize, 2 * MiB);
210 
211     fdt_pack(fdt);
212     /* copy in the device tree */
213     qemu_fdt_dumpdtb(fdt, fdtsize);
214 
215     rom_add_blob_fixed_as("fdt", fdt, fdtsize, fdt_addr,
216                           &address_space_memory);
217 
218     return fdt_addr;
219 }
220 
221 void riscv_rom_copy_firmware_info(hwaddr rom_base, hwaddr rom_size,
222                               uint32_t reset_vec_size, uint64_t kernel_entry)
223 {
224     struct fw_dynamic_info dinfo;
225     size_t dinfo_len;
226 
227     dinfo.magic = fw_dynamic_info_data(FW_DYNAMIC_INFO_MAGIC_VALUE);
228     dinfo.version = fw_dynamic_info_data(FW_DYNAMIC_INFO_VERSION);
229     dinfo.next_mode = fw_dynamic_info_data(FW_DYNAMIC_INFO_NEXT_MODE_S);
230     dinfo.next_addr = fw_dynamic_info_data(kernel_entry);
231     dinfo.options = 0;
232     dinfo.boot_hart = 0;
233     dinfo_len = sizeof(dinfo);
234 
235     /**
236      * copy the dynamic firmware info. This information is specific to
237      * OpenSBI but doesn't break any other firmware as long as they don't
238      * expect any certain value in "a2" register.
239      */
240     if (dinfo_len > (rom_size - reset_vec_size)) {
241         error_report("not enough space to store dynamic firmware info");
242         exit(1);
243     }
244 
245     rom_add_blob_fixed_as("mrom.finfo", &dinfo, dinfo_len,
246                            rom_base + reset_vec_size,
247                            &address_space_memory);
248 }
249 
250 void riscv_setup_rom_reset_vec(hwaddr start_addr, hwaddr rom_base,
251                                hwaddr rom_size, uint64_t kernel_entry,
252                                uint32_t fdt_load_addr, void *fdt)
253 {
254     int i;
255     uint32_t start_addr_hi32 = 0x00000000;
256 
257     #if defined(TARGET_RISCV64)
258     start_addr_hi32 = start_addr >> 32;
259     #endif
260     /* reset vector */
261     uint32_t reset_vec[10] = {
262         0x00000297,                  /* 1:  auipc  t0, %pcrel_hi(fw_dyn) */
263         0x02828613,                  /*     addi   a2, t0, %pcrel_lo(1b) */
264         0xf1402573,                  /*     csrr   a0, mhartid  */
265 #if defined(TARGET_RISCV32)
266         0x0202a583,                  /*     lw     a1, 32(t0) */
267         0x0182a283,                  /*     lw     t0, 24(t0) */
268 #elif defined(TARGET_RISCV64)
269         0x0202b583,                  /*     ld     a1, 32(t0) */
270         0x0182b283,                  /*     ld     t0, 24(t0) */
271 #endif
272         0x00028067,                  /*     jr     t0 */
273         start_addr,                  /* start: .dword */
274         start_addr_hi32,
275         fdt_load_addr,               /* fdt_laddr: .dword */
276         0x00000000,
277                                      /* fw_dyn: */
278     };
279 
280     /* copy in the reset vector in little_endian byte order */
281     for (i = 0; i < ARRAY_SIZE(reset_vec); i++) {
282         reset_vec[i] = cpu_to_le32(reset_vec[i]);
283     }
284     rom_add_blob_fixed_as("mrom.reset", reset_vec, sizeof(reset_vec),
285                           rom_base, &address_space_memory);
286     riscv_rom_copy_firmware_info(rom_base, rom_size, sizeof(reset_vec),
287                                  kernel_entry);
288 
289     return;
290 }
291