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 "exec/address-spaces.h"
44 #include "qemu/error-report.h"
45 #include "sysemu/qtest.h"
46 #include "sysemu/reset.h"
47 
48 static struct _loaderparams {
49     int ram_size;
50     const char *kernel_filename;
51     const char *kernel_cmdline;
52     const char *initrd_filename;
53 } loaderparams;
54 
55 typedef struct ResetData {
56     MIPSCPU *cpu;
57     uint64_t vector;
58 } ResetData;
59 
load_kernel(void)60 static int64_t load_kernel(void)
61 {
62     int64_t entry, kernel_high, initrd_size;
63     long kernel_size;
64     ram_addr_t initrd_offset;
65     int big_endian;
66 
67 #ifdef TARGET_WORDS_BIGENDIAN
68     big_endian = 1;
69 #else
70     big_endian = 0;
71 #endif
72 
73     kernel_size = load_elf(loaderparams.kernel_filename, NULL,
74                            cpu_mips_kseg0_to_phys, NULL,
75                            (uint64_t *)&entry, NULL,
76                            (uint64_t *)&kernel_high, big_endian,
77                            EM_MIPS, 1, 0);
78     if (kernel_size >= 0) {
79         if ((entry & ~0x7fffffffULL) == 0x80000000) {
80             entry = (int32_t)entry;
81         }
82     } else {
83         error_report("could not load kernel '%s': %s",
84                      loaderparams.kernel_filename,
85                      load_elf_strerror(kernel_size));
86         exit(1);
87     }
88 
89     /* load initrd */
90     initrd_size = 0;
91     initrd_offset = 0;
92     if (loaderparams.initrd_filename) {
93         initrd_size = get_image_size(loaderparams.initrd_filename);
94         if (initrd_size > 0) {
95             initrd_offset = (kernel_high + ~INITRD_PAGE_MASK) &
96                             INITRD_PAGE_MASK;
97             if (initrd_offset + initrd_size > loaderparams.ram_size) {
98                 error_report("memory too small for initial ram disk '%s'",
99                              loaderparams.initrd_filename);
100                 exit(1);
101             }
102             initrd_size = load_image_targphys(loaderparams.initrd_filename,
103                 initrd_offset, loaderparams.ram_size - initrd_offset);
104         }
105         if (initrd_size == (target_ulong) -1) {
106             error_report("could not load initial ram disk '%s'",
107                          loaderparams.initrd_filename);
108             exit(1);
109         }
110     }
111     return entry;
112 }
113 
main_cpu_reset(void * opaque)114 static void main_cpu_reset(void *opaque)
115 {
116     ResetData *s = (ResetData *)opaque;
117     CPUMIPSState *env = &s->cpu->env;
118 
119     cpu_reset(CPU(s->cpu));
120     env->active_tc.PC = s->vector & ~(target_ulong)1;
121     if (s->vector & 1) {
122         env->hflags |= MIPS_HFLAG_M16;
123     }
124 }
125 
mipsnet_init(int base,qemu_irq irq,NICInfo * nd)126 static void mipsnet_init(int base, qemu_irq irq, NICInfo *nd)
127 {
128     DeviceState *dev;
129     SysBusDevice *s;
130 
131     dev = qdev_create(NULL, "mipsnet");
132     qdev_set_nic_properties(dev, nd);
133     qdev_init_nofail(dev);
134 
135     s = SYS_BUS_DEVICE(dev);
136     sysbus_connect_irq(s, 0, irq);
137     memory_region_add_subregion(get_system_io(),
138                                 base,
139                                 sysbus_mmio_get_region(s, 0));
140 }
141 
142 static void
mips_mipssim_init(MachineState * machine)143 mips_mipssim_init(MachineState *machine)
144 {
145     ram_addr_t ram_size = machine->ram_size;
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 *ram = g_new(MemoryRegion, 1);
153     MemoryRegion *bios = g_new(MemoryRegion, 1);
154     MIPSCPU *cpu;
155     CPUMIPSState *env;
156     ResetData *reset_info;
157     int bios_size;
158 
159     /* Init CPUs. */
160     cpu = MIPS_CPU(cpu_create(machine->cpu_type));
161     env = &cpu->env;
162 
163     reset_info = g_malloc0(sizeof(ResetData));
164     reset_info->cpu = cpu;
165     reset_info->vector = env->active_tc.PC;
166     qemu_register_reset(main_cpu_reset, reset_info);
167 
168     /* Allocate RAM. */
169     memory_region_allocate_system_memory(ram, NULL, "mips_mipssim.ram",
170                                          ram_size);
171     memory_region_init_ram(bios, NULL, "mips_mipssim.bios", BIOS_SIZE,
172                            &error_fatal);
173     memory_region_set_readonly(bios, true);
174 
175     memory_region_add_subregion(address_space_mem, 0, 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     if (bios_name == NULL) {
181         bios_name = BIOS_FILENAME;
182     }
183     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
184     if (filename) {
185         bios_size = load_image_targphys(filename, 0x1fc00000LL, BIOS_SIZE);
186         g_free(filename);
187     } else {
188         bios_size = -1;
189     }
190     if ((bios_size < 0 || bios_size > BIOS_SIZE) &&
191         !kernel_filename && !qtest_enabled()) {
192         /* Bail out if we have neither a kernel image nor boot vector code. */
193         error_report("Could not load MIPS bios '%s', and no "
194                      "-kernel argument was specified", bios_name);
195         exit(1);
196     } else {
197         /* We have a boot vector start address. */
198         env->active_tc.PC = (target_long)(int32_t)0xbfc00000;
199     }
200 
201     if (kernel_filename) {
202         loaderparams.ram_size = ram_size;
203         loaderparams.kernel_filename = kernel_filename;
204         loaderparams.kernel_cmdline = kernel_cmdline;
205         loaderparams.initrd_filename = initrd_filename;
206         reset_info->vector = load_kernel();
207     }
208 
209     /* Init CPU internal devices. */
210     cpu_mips_irq_init_cpu(cpu);
211     cpu_mips_clock_init(cpu);
212 
213     /* Register 64 KB of ISA IO space at 0x1fd00000. */
214     memory_region_init_alias(isa, NULL, "isa_mmio",
215                              get_system_io(), 0, 0x00010000);
216     memory_region_add_subregion(get_system_memory(), 0x1fd00000, isa);
217 
218     /*
219      * A single 16450 sits at offset 0x3f8. It is attached to
220      * MIPS CPU INT2, which is interrupt 4.
221      */
222     if (serial_hd(0))
223         serial_init(0x3f8, env->irq[4], 115200, serial_hd(0),
224                     get_system_io());
225 
226     if (nd_table[0].used)
227         /* MIPSnet uses the MIPS CPU INT0, which is interrupt 2. */
228         mipsnet_init(0x4200, env->irq[2], &nd_table[0]);
229 }
230 
mips_mipssim_machine_init(MachineClass * mc)231 static void mips_mipssim_machine_init(MachineClass *mc)
232 {
233     mc->desc = "MIPS MIPSsim platform";
234     mc->init = mips_mipssim_init;
235 #ifdef TARGET_MIPS64
236     mc->default_cpu_type = MIPS_CPU_TYPE_NAME("5Kf");
237 #else
238     mc->default_cpu_type = MIPS_CPU_TYPE_NAME("24Kf");
239 #endif
240 }
241 
242 DEFINE_MACHINE("mipssim", mips_mipssim_machine_init)
243