xref: /openbmc/qemu/hw/nios2/boot.c (revision b355f08a)
1 /*
2  * Nios2 kernel loader
3  *
4  * Copyright (c) 2016 Marek Vasut <marek.vasut@gmail.com>
5  *
6  * Based on microblaze kernel loader
7  *
8  * Copyright (c) 2012 Peter Crosthwaite <peter.crosthwaite@petalogix.com>
9  * Copyright (c) 2012 PetaLogix
10  * Copyright (c) 2009 Edgar E. Iglesias.
11  *
12  * Permission is hereby granted, free of charge, to any person obtaining a copy
13  * of this software and associated documentation files (the "Software"), to deal
14  * in the Software without restriction, including without limitation the rights
15  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
16  * copies of the Software, and to permit persons to whom the Software is
17  * furnished to do so, subject to the following conditions:
18  *
19  * The above copyright notice and this permission notice shall be included in
20  * all copies or substantial portions of the Software.
21  *
22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
25  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
26  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
27  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
28  * THE SOFTWARE.
29  */
30 
31 #include "qemu/osdep.h"
32 #include "qemu/units.h"
33 #include "qemu-common.h"
34 #include "qemu/datadir.h"
35 #include "qemu/option.h"
36 #include "qemu/config-file.h"
37 #include "qemu/error-report.h"
38 #include "sysemu/device_tree.h"
39 #include "sysemu/reset.h"
40 #include "hw/boards.h"
41 #include "hw/loader.h"
42 #include "elf.h"
43 
44 #include "boot.h"
45 
46 #define NIOS2_MAGIC    0x534f494e
47 
48 static struct nios2_boot_info {
49     void (*machine_cpu_reset)(Nios2CPU *);
50     uint32_t bootstrap_pc;
51     uint32_t cmdline;
52     uint32_t initrd_start;
53     uint32_t initrd_end;
54     uint32_t fdt;
55 } boot_info;
56 
57 static void main_cpu_reset(void *opaque)
58 {
59     Nios2CPU *cpu = opaque;
60     CPUState *cs = CPU(cpu);
61     CPUNios2State *env = &cpu->env;
62 
63     cpu_reset(CPU(cpu));
64 
65     env->regs[R_ARG0] = NIOS2_MAGIC;
66     env->regs[R_ARG1] = boot_info.initrd_start;
67     env->regs[R_ARG2] = boot_info.fdt;
68     env->regs[R_ARG3] = boot_info.cmdline;
69 
70     cpu_set_pc(cs, boot_info.bootstrap_pc);
71     if (boot_info.machine_cpu_reset) {
72         boot_info.machine_cpu_reset(cpu);
73     }
74 }
75 
76 static uint64_t translate_kernel_address(void *opaque, uint64_t addr)
77 {
78     return addr - 0xc0000000LL;
79 }
80 
81 static int nios2_load_dtb(struct nios2_boot_info bi, const uint32_t ramsize,
82                           const char *kernel_cmdline, const char *dtb_filename)
83 {
84     int fdt_size;
85     void *fdt = NULL;
86     int r;
87 
88     if (dtb_filename) {
89         fdt = load_device_tree(dtb_filename, &fdt_size);
90     }
91     if (!fdt) {
92         return 0;
93     }
94 
95     if (kernel_cmdline) {
96         r = qemu_fdt_setprop_string(fdt, "/chosen", "bootargs",
97                                     kernel_cmdline);
98         if (r < 0) {
99             fprintf(stderr, "couldn't set /chosen/bootargs\n");
100         }
101     }
102 
103     if (bi.initrd_start) {
104         qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-start",
105                               translate_kernel_address(NULL, bi.initrd_start));
106 
107         qemu_fdt_setprop_cell(fdt, "/chosen", "linux,initrd-end",
108                               translate_kernel_address(NULL, bi.initrd_end));
109     }
110 
111     cpu_physical_memory_write(bi.fdt, fdt, fdt_size);
112     g_free(fdt);
113     return fdt_size;
114 }
115 
116 void nios2_load_kernel(Nios2CPU *cpu, hwaddr ddr_base,
117                             uint32_t ramsize,
118                             const char *initrd_filename,
119                             const char *dtb_filename,
120                             void (*machine_cpu_reset)(Nios2CPU *))
121 {
122     const char *kernel_filename;
123     const char *kernel_cmdline;
124     const char *dtb_arg;
125     char *filename = NULL;
126 
127     kernel_filename = current_machine->kernel_filename;
128     kernel_cmdline = current_machine->kernel_cmdline;
129     dtb_arg = current_machine->dtb;
130     /* default to pcbios dtb as passed by machine_init */
131     if (!dtb_arg) {
132         filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, dtb_filename);
133     }
134 
135     boot_info.machine_cpu_reset = machine_cpu_reset;
136     qemu_register_reset(main_cpu_reset, cpu);
137 
138     if (kernel_filename) {
139         int kernel_size, fdt_size;
140         uint64_t entry, high;
141         int big_endian = 0;
142 
143 #ifdef TARGET_WORDS_BIGENDIAN
144         big_endian = 1;
145 #endif
146 
147         /* Boots a kernel elf binary. */
148         kernel_size = load_elf(kernel_filename, NULL, NULL, NULL,
149                                &entry, NULL, &high, NULL,
150                                big_endian, EM_ALTERA_NIOS2, 0, 0);
151         if ((uint32_t)entry == 0xc0000000) {
152             /*
153              * The Nios II processor reference guide documents that the
154              * kernel is placed at virtual memory address 0xc0000000,
155              * and we've got something that points there.  Reload it
156              * and adjust the entry to get the address in physical RAM.
157              */
158             kernel_size = load_elf(kernel_filename, NULL,
159                                    translate_kernel_address, NULL,
160                                    &entry, NULL, NULL, NULL,
161                                    big_endian, EM_ALTERA_NIOS2, 0, 0);
162             boot_info.bootstrap_pc = ddr_base + 0xc0000000 +
163                 (entry & 0x07ffffff);
164         } else {
165             /* Use the entry point in the ELF image.  */
166             boot_info.bootstrap_pc = (uint32_t)entry;
167         }
168 
169         /* If it wasn't an ELF image, try an u-boot image. */
170         if (kernel_size < 0) {
171             hwaddr uentry, loadaddr = LOAD_UIMAGE_LOADADDR_INVALID;
172 
173             kernel_size = load_uimage(kernel_filename, &uentry, &loadaddr, 0,
174                                       NULL, NULL);
175             boot_info.bootstrap_pc = uentry;
176             high = loadaddr + kernel_size;
177         }
178 
179         /* Not an ELF image nor an u-boot image, try a RAW image. */
180         if (kernel_size < 0) {
181             kernel_size = load_image_targphys(kernel_filename, ddr_base,
182                                               ramsize);
183             boot_info.bootstrap_pc = ddr_base;
184             high = ddr_base + kernel_size;
185         }
186 
187         high = ROUND_UP(high, 1 * MiB);
188 
189         /* If initrd is available, it goes after the kernel, aligned to 1M. */
190         if (initrd_filename) {
191             int initrd_size;
192             uint32_t initrd_offset;
193 
194             boot_info.initrd_start = high;
195             initrd_offset = boot_info.initrd_start - ddr_base;
196 
197             initrd_size = load_ramdisk(initrd_filename,
198                                        boot_info.initrd_start,
199                                        ramsize - initrd_offset);
200             if (initrd_size < 0) {
201                 initrd_size = load_image_targphys(initrd_filename,
202                                                   boot_info.initrd_start,
203                                                   ramsize - initrd_offset);
204             }
205             if (initrd_size < 0) {
206                 error_report("could not load initrd '%s'",
207                              initrd_filename);
208                 exit(EXIT_FAILURE);
209             }
210             high += initrd_size;
211         }
212         high = ROUND_UP(high, 4);
213         boot_info.initrd_end = high;
214 
215         /* Device tree must be placed right after initrd (if available) */
216         boot_info.fdt = high;
217         fdt_size = nios2_load_dtb(boot_info, ramsize, kernel_cmdline,
218                                   /* Preference a -dtb argument */
219                                   dtb_arg ? dtb_arg : filename);
220         high += fdt_size;
221 
222         /* Kernel command is at the end, 4k aligned. */
223         boot_info.cmdline = ROUND_UP(high, 4 * KiB);
224         if (kernel_cmdline && strlen(kernel_cmdline)) {
225             pstrcpy_targphys("cmdline", boot_info.cmdline, 256, kernel_cmdline);
226         }
227     }
228     g_free(filename);
229 }
230