xref: /openbmc/qemu/hw/mips/mipssim.c (revision 61f3c91a)
1 /*
2  * QEMU/mipssim emulation
3  *
4  * Emulates a very simple machine model similar to the one used by the
5  * proprietary MIPS emulator.
6  *
7  * Copyright (c) 2007 Thiemo Seufer
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a copy
10  * of this software and associated documentation files (the "Software"), to deal
11  * in the Software without restriction, including without limitation the rights
12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13  * copies of the Software, and to permit persons to whom the Software is
14  * furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25  * THE SOFTWARE.
26  */
27 
28 #include "qemu/osdep.h"
29 #include "qapi/error.h"
30 #include "qemu-common.h"
31 #include "cpu.h"
32 #include "hw/clock.h"
33 #include "hw/mips/mips.h"
34 #include "hw/mips/cpudevs.h"
35 #include "hw/char/serial.h"
36 #include "hw/isa/isa.h"
37 #include "net/net.h"
38 #include "sysemu/sysemu.h"
39 #include "hw/boards.h"
40 #include "hw/mips/bios.h"
41 #include "hw/loader.h"
42 #include "elf.h"
43 #include "hw/sysbus.h"
44 #include "hw/qdev-properties.h"
45 #include "exec/address-spaces.h"
46 #include "qemu/error-report.h"
47 #include "sysemu/qtest.h"
48 #include "sysemu/reset.h"
49 
50 static struct _loaderparams {
51     int ram_size;
52     const char *kernel_filename;
53     const char *kernel_cmdline;
54     const char *initrd_filename;
55 } loaderparams;
56 
57 typedef struct ResetData {
58     MIPSCPU *cpu;
59     uint64_t vector;
60 } ResetData;
61 
62 static int64_t load_kernel(void)
63 {
64     int64_t entry, kernel_high, initrd_size;
65     long kernel_size;
66     ram_addr_t initrd_offset;
67     int big_endian;
68 
69 #ifdef TARGET_WORDS_BIGENDIAN
70     big_endian = 1;
71 #else
72     big_endian = 0;
73 #endif
74 
75     kernel_size = load_elf(loaderparams.kernel_filename, NULL,
76                            cpu_mips_kseg0_to_phys, NULL,
77                            (uint64_t *)&entry, NULL,
78                            (uint64_t *)&kernel_high, NULL, big_endian,
79                            EM_MIPS, 1, 0);
80     if (kernel_size < 0) {
81         error_report("could not load kernel '%s': %s",
82                      loaderparams.kernel_filename,
83                      load_elf_strerror(kernel_size));
84         exit(1);
85     }
86 
87     /* load initrd */
88     initrd_size = 0;
89     initrd_offset = 0;
90     if (loaderparams.initrd_filename) {
91         initrd_size = get_image_size(loaderparams.initrd_filename);
92         if (initrd_size > 0) {
93             initrd_offset = ROUND_UP(kernel_high, INITRD_PAGE_SIZE);
94             if (initrd_offset + initrd_size > loaderparams.ram_size) {
95                 error_report("memory too small for initial ram disk '%s'",
96                              loaderparams.initrd_filename);
97                 exit(1);
98             }
99             initrd_size = load_image_targphys(loaderparams.initrd_filename,
100                 initrd_offset, loaderparams.ram_size - initrd_offset);
101         }
102         if (initrd_size == (target_ulong) -1) {
103             error_report("could not load initial ram disk '%s'",
104                          loaderparams.initrd_filename);
105             exit(1);
106         }
107     }
108     return entry;
109 }
110 
111 static void main_cpu_reset(void *opaque)
112 {
113     ResetData *s = (ResetData *)opaque;
114     CPUMIPSState *env = &s->cpu->env;
115 
116     cpu_reset(CPU(s->cpu));
117     env->active_tc.PC = s->vector & ~(target_ulong)1;
118     if (s->vector & 1) {
119         env->hflags |= MIPS_HFLAG_M16;
120     }
121 }
122 
123 static void mipsnet_init(int base, qemu_irq irq, NICInfo *nd)
124 {
125     DeviceState *dev;
126     SysBusDevice *s;
127 
128     dev = qdev_new("mipsnet");
129     qdev_set_nic_properties(dev, nd);
130 
131     s = SYS_BUS_DEVICE(dev);
132     sysbus_realize_and_unref(s, &error_fatal);
133     sysbus_connect_irq(s, 0, irq);
134     memory_region_add_subregion(get_system_io(),
135                                 base,
136                                 sysbus_mmio_get_region(s, 0));
137 }
138 
139 static void
140 mips_mipssim_init(MachineState *machine)
141 {
142     const char *kernel_filename = machine->kernel_filename;
143     const char *kernel_cmdline = machine->kernel_cmdline;
144     const char *initrd_filename = machine->initrd_filename;
145     char *filename;
146     MemoryRegion *address_space_mem = get_system_memory();
147     MemoryRegion *isa = g_new(MemoryRegion, 1);
148     MemoryRegion *bios = g_new(MemoryRegion, 1);
149     Clock *cpuclk;
150     MIPSCPU *cpu;
151     CPUMIPSState *env;
152     ResetData *reset_info;
153     int bios_size;
154 
155     cpuclk = clock_new(OBJECT(machine), "cpu-refclk");
156 #ifdef TARGET_MIPS64
157     clock_set_hz(cpuclk, 6000000); /* 6 MHz */
158 #else
159     clock_set_hz(cpuclk, 12000000); /* 12 MHz */
160 #endif
161 
162     /* Init CPUs. */
163     cpu = mips_cpu_create_with_clock(machine->cpu_type, cpuclk);
164     env = &cpu->env;
165 
166     reset_info = g_malloc0(sizeof(ResetData));
167     reset_info->cpu = cpu;
168     reset_info->vector = env->active_tc.PC;
169     qemu_register_reset(main_cpu_reset, reset_info);
170 
171     /* Allocate RAM. */
172     memory_region_init_rom(bios, NULL, "mips_mipssim.bios", BIOS_SIZE,
173                            &error_fatal);
174 
175     memory_region_add_subregion(address_space_mem, 0, machine->ram);
176 
177     /* Map the BIOS / boot exception handler. */
178     memory_region_add_subregion(address_space_mem, 0x1fc00000LL, bios);
179     /* Load a BIOS / boot exception handler image. */
180     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name ?: BIOS_FILENAME);
181     if (filename) {
182         bios_size = load_image_targphys(filename, 0x1fc00000LL, BIOS_SIZE);
183         g_free(filename);
184     } else {
185         bios_size = -1;
186     }
187     if ((bios_size < 0 || bios_size > BIOS_SIZE) &&
188         bios_name && !qtest_enabled()) {
189         /* Bail out if we have neither a kernel image nor boot vector code. */
190         error_report("Could not load MIPS bios '%s'", bios_name);
191         exit(1);
192     } else {
193         /* We have a boot vector start address. */
194         env->active_tc.PC = (target_long)(int32_t)0xbfc00000;
195     }
196 
197     if (kernel_filename) {
198         loaderparams.ram_size = machine->ram_size;
199         loaderparams.kernel_filename = kernel_filename;
200         loaderparams.kernel_cmdline = kernel_cmdline;
201         loaderparams.initrd_filename = initrd_filename;
202         reset_info->vector = load_kernel();
203     }
204 
205     /* Init CPU internal devices. */
206     cpu_mips_irq_init_cpu(cpu);
207     cpu_mips_clock_init(cpu);
208 
209     /* Register 64 KB of ISA IO space at 0x1fd00000. */
210     memory_region_init_alias(isa, NULL, "isa_mmio",
211                              get_system_io(), 0, 0x00010000);
212     memory_region_add_subregion(get_system_memory(), 0x1fd00000, isa);
213 
214     /*
215      * A single 16450 sits at offset 0x3f8. It is attached to
216      * MIPS CPU INT2, which is interrupt 4.
217      */
218     if (serial_hd(0)) {
219         DeviceState *dev = qdev_new(TYPE_SERIAL_MM);
220 
221         qdev_prop_set_chr(dev, "chardev", serial_hd(0));
222         qdev_prop_set_uint8(dev, "regshift", 0);
223         qdev_prop_set_uint8(dev, "endianness", DEVICE_LITTLE_ENDIAN);
224         sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
225         sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, env->irq[4]);
226         sysbus_add_io(SYS_BUS_DEVICE(dev), 0x3f8,
227                       sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0));
228     }
229 
230     if (nd_table[0].used)
231         /* MIPSnet uses the MIPS CPU INT0, which is interrupt 2. */
232         mipsnet_init(0x4200, env->irq[2], &nd_table[0]);
233 }
234 
235 static void mips_mipssim_machine_init(MachineClass *mc)
236 {
237     mc->desc = "MIPS MIPSsim platform";
238     mc->init = mips_mipssim_init;
239 #ifdef TARGET_MIPS64
240     mc->default_cpu_type = MIPS_CPU_TYPE_NAME("5Kf");
241 #else
242     mc->default_cpu_type = MIPS_CPU_TYPE_NAME("24Kf");
243 #endif
244     mc->default_ram_id = "mips_mipssim.ram";
245 }
246 
247 DEFINE_MACHINE("mipssim", mips_mipssim_machine_init)
248