xref: /openbmc/qemu/hw/mips/mipssim.c (revision 2055dbc1)
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/mips/mips.h"
33 #include "hw/mips/cpudevs.h"
34 #include "hw/char/serial.h"
35 #include "hw/isa/isa.h"
36 #include "net/net.h"
37 #include "sysemu/sysemu.h"
38 #include "hw/boards.h"
39 #include "hw/mips/bios.h"
40 #include "hw/loader.h"
41 #include "elf.h"
42 #include "hw/sysbus.h"
43 #include "hw/qdev-properties.h"
44 #include "exec/address-spaces.h"
45 #include "qemu/error-report.h"
46 #include "sysemu/qtest.h"
47 #include "sysemu/reset.h"
48 
49 static struct _loaderparams {
50     int ram_size;
51     const char *kernel_filename;
52     const char *kernel_cmdline;
53     const char *initrd_filename;
54 } loaderparams;
55 
56 typedef struct ResetData {
57     MIPSCPU *cpu;
58     uint64_t vector;
59 } ResetData;
60 
61 static int64_t load_kernel(void)
62 {
63     int64_t entry, kernel_high, initrd_size;
64     long kernel_size;
65     ram_addr_t initrd_offset;
66     int big_endian;
67 
68 #ifdef TARGET_WORDS_BIGENDIAN
69     big_endian = 1;
70 #else
71     big_endian = 0;
72 #endif
73 
74     kernel_size = load_elf(loaderparams.kernel_filename, NULL,
75                            cpu_mips_kseg0_to_phys, NULL,
76                            (uint64_t *)&entry, NULL,
77                            (uint64_t *)&kernel_high, NULL, big_endian,
78                            EM_MIPS, 1, 0);
79     if (kernel_size >= 0) {
80         if ((entry & ~0x7fffffffULL) == 0x80000000) {
81             entry = (int32_t)entry;
82         }
83     } else {
84         error_report("could not load kernel '%s': %s",
85                      loaderparams.kernel_filename,
86                      load_elf_strerror(kernel_size));
87         exit(1);
88     }
89 
90     /* load initrd */
91     initrd_size = 0;
92     initrd_offset = 0;
93     if (loaderparams.initrd_filename) {
94         initrd_size = get_image_size(loaderparams.initrd_filename);
95         if (initrd_size > 0) {
96             initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
97                             INITRD_PAGE_MASK;
98             if (initrd_offset + initrd_size > loaderparams.ram_size) {
99                 error_report("memory too small for initial ram disk '%s'",
100                              loaderparams.initrd_filename);
101                 exit(1);
102             }
103             initrd_size = load_image_targphys(loaderparams.initrd_filename,
104                 initrd_offset, loaderparams.ram_size - initrd_offset);
105         }
106         if (initrd_size == (target_ulong) -1) {
107             error_report("could not load initial ram disk '%s'",
108                          loaderparams.initrd_filename);
109             exit(1);
110         }
111     }
112     return entry;
113 }
114 
115 static void main_cpu_reset(void *opaque)
116 {
117     ResetData *s = (ResetData *)opaque;
118     CPUMIPSState *env = &s->cpu->env;
119 
120     cpu_reset(CPU(s->cpu));
121     env->active_tc.PC = s->vector & ~(target_ulong)1;
122     if (s->vector & 1) {
123         env->hflags |= MIPS_HFLAG_M16;
124     }
125 }
126 
127 static void mipsnet_init(int base, qemu_irq irq, NICInfo *nd)
128 {
129     DeviceState *dev;
130     SysBusDevice *s;
131 
132     dev = qdev_new("mipsnet");
133     qdev_set_nic_properties(dev, nd);
134 
135     s = SYS_BUS_DEVICE(dev);
136     sysbus_realize_and_unref(s, &error_fatal);
137     sysbus_connect_irq(s, 0, irq);
138     memory_region_add_subregion(get_system_io(),
139                                 base,
140                                 sysbus_mmio_get_region(s, 0));
141 }
142 
143 static void
144 mips_mipssim_init(MachineState *machine)
145 {
146     const char *kernel_filename = machine->kernel_filename;
147     const char *kernel_cmdline = machine->kernel_cmdline;
148     const char *initrd_filename = machine->initrd_filename;
149     char *filename;
150     MemoryRegion *address_space_mem = get_system_memory();
151     MemoryRegion *isa = g_new(MemoryRegion, 1);
152     MemoryRegion *bios = g_new(MemoryRegion, 1);
153     MIPSCPU *cpu;
154     CPUMIPSState *env;
155     ResetData *reset_info;
156     int bios_size;
157 
158     /* Init CPUs. */
159     cpu = MIPS_CPU(cpu_create(machine->cpu_type));
160     env = &cpu->env;
161 
162     reset_info = g_malloc0(sizeof(ResetData));
163     reset_info->cpu = cpu;
164     reset_info->vector = env->active_tc.PC;
165     qemu_register_reset(main_cpu_reset, reset_info);
166 
167     /* Allocate RAM. */
168     memory_region_init_rom(bios, NULL, "mips_mipssim.bios", BIOS_SIZE,
169                            &error_fatal);
170 
171     memory_region_add_subregion(address_space_mem, 0, machine->ram);
172 
173     /* Map the BIOS / boot exception handler. */
174     memory_region_add_subregion(address_space_mem, 0x1fc00000LL, bios);
175     /* Load a BIOS / boot exception handler image. */
176     if (bios_name == NULL) {
177         bios_name = BIOS_FILENAME;
178     }
179     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
180     if (filename) {
181         bios_size = load_image_targphys(filename, 0x1fc00000LL, BIOS_SIZE);
182         g_free(filename);
183     } else {
184         bios_size = -1;
185     }
186     if ((bios_size < 0 || bios_size > BIOS_SIZE) &&
187         !kernel_filename && !qtest_enabled()) {
188         /* Bail out if we have neither a kernel image nor boot vector code. */
189         error_report("Could not load MIPS bios '%s', and no "
190                      "-kernel argument was specified", 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_IO);
220 
221         qdev_prop_set_chr(dev, "chardev", serial_hd(0));
222         qdev_set_legacy_instance_id(dev, 0x3f8, 2);
223         sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
224         sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, env->irq[4]);
225         sysbus_add_io(SYS_BUS_DEVICE(dev), 0x3f8,
226                       sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0));
227     }
228 
229     if (nd_table[0].used)
230         /* MIPSnet uses the MIPS CPU INT0, which is interrupt 2. */
231         mipsnet_init(0x4200, env->irq[2], &nd_table[0]);
232 }
233 
234 static void mips_mipssim_machine_init(MachineClass *mc)
235 {
236     mc->desc = "MIPS MIPSsim platform";
237     mc->init = mips_mipssim_init;
238 #ifdef TARGET_MIPS64
239     mc->default_cpu_type = MIPS_CPU_TYPE_NAME("5Kf");
240 #else
241     mc->default_cpu_type = MIPS_CPU_TYPE_NAME("24Kf");
242 #endif
243     mc->default_ram_id = "mips_mipssim.ram";
244 }
245 
246 DEFINE_MACHINE("mipssim", mips_mipssim_machine_init)
247