xref: /openbmc/qemu/hw/mips/mipssim.c (revision c3a68dfd191682b140951e423b72866102097df9)
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/datadir.h"
31  #include "exec/address-spaces.h"
32  #include "hw/clock.h"
33  #include "hw/mips/mips.h"
34  #include "hw/char/serial.h"
35  #include "net/net.h"
36  #include "sysemu/sysemu.h"
37  #include "hw/boards.h"
38  #include "hw/loader.h"
39  #include "elf.h"
40  #include "hw/sysbus.h"
41  #include "hw/qdev-properties.h"
42  #include "qemu/error-report.h"
43  #include "sysemu/qtest.h"
44  #include "sysemu/reset.h"
45  #include "cpu.h"
46  
47  #define BIOS_SIZE (4 * MiB)
48  
49  #if TARGET_BIG_ENDIAN
50  #define BIOS_FILENAME "mips_bios.bin"
51  #else
52  #define BIOS_FILENAME "mipsel_bios.bin"
53  #endif
54  
55  static struct _loaderparams {
56      int ram_size;
57      const char *kernel_filename;
58      const char *kernel_cmdline;
59      const char *initrd_filename;
60  } loaderparams;
61  
62  typedef struct ResetData {
63      MIPSCPU *cpu;
64      uint64_t vector;
65  } ResetData;
66  
67  static uint64_t load_kernel(void)
68  {
69      uint64_t entry, kernel_high, initrd_size;
70      long kernel_size;
71      ram_addr_t initrd_offset;
72  
73      kernel_size = load_elf(loaderparams.kernel_filename, NULL,
74                             cpu_mips_kseg0_to_phys, NULL,
75                             &entry, NULL,
76                             &kernel_high, NULL, TARGET_BIG_ENDIAN,
77                             EM_MIPS, 1, 0);
78      if (kernel_size < 0) {
79          error_report("could not load kernel '%s': %s",
80                       loaderparams.kernel_filename,
81                       load_elf_strerror(kernel_size));
82          exit(1);
83      }
84  
85      /* load initrd */
86      initrd_size = 0;
87      initrd_offset = 0;
88      if (loaderparams.initrd_filename) {
89          initrd_size = get_image_size(loaderparams.initrd_filename);
90          if (initrd_size > 0) {
91              initrd_offset = ROUND_UP(kernel_high, INITRD_PAGE_SIZE);
92              if (initrd_offset + initrd_size > loaderparams.ram_size) {
93                  error_report("memory too small for initial ram disk '%s'",
94                               loaderparams.initrd_filename);
95                  exit(1);
96              }
97              initrd_size = load_image_targphys(loaderparams.initrd_filename,
98                  initrd_offset, loaderparams.ram_size - initrd_offset);
99          }
100          if (initrd_size == (target_ulong) -1) {
101              error_report("could not load initial ram disk '%s'",
102                           loaderparams.initrd_filename);
103              exit(1);
104          }
105      }
106      return entry;
107  }
108  
109  static void main_cpu_reset(void *opaque)
110  {
111      ResetData *s = (ResetData *)opaque;
112      CPUMIPSState *env = &s->cpu->env;
113  
114      cpu_reset(CPU(s->cpu));
115      env->active_tc.PC = s->vector & ~(target_ulong)1;
116      if (s->vector & 1) {
117          env->hflags |= MIPS_HFLAG_M16;
118      }
119  }
120  
121  static void mipsnet_init(int base, qemu_irq irq)
122  {
123      DeviceState *dev;
124      SysBusDevice *s;
125  
126      dev = qemu_create_nic_device("mipsnet", true, NULL);
127      if (!dev) {
128          return;
129      }
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_new0(ResetData, 1);
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, machine->firmware ?: 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          machine->firmware && !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'", machine->firmware);
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      /*
210       * Register 64 KB of ISA IO space at 0x1fd00000.  But without interrupts
211       * (except for the hardcoded serial port interrupt) -device cannot work,
212       * so do not expose the ISA bus to the user.
213       */
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          DeviceState *dev = qdev_new(TYPE_SERIAL_MM);
224  
225          qdev_prop_set_chr(dev, "chardev", serial_hd(0));
226          qdev_prop_set_uint8(dev, "regshift", 0);
227          qdev_prop_set_uint8(dev, "endianness", DEVICE_LITTLE_ENDIAN);
228          sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
229          sysbus_connect_irq(SYS_BUS_DEVICE(dev), 0, env->irq[4]);
230          memory_region_add_subregion(get_system_io(), 0x3f8,
231                        sysbus_mmio_get_region(SYS_BUS_DEVICE(dev), 0));
232      }
233  
234      /* MIPSnet uses the MIPS CPU INT0, which is interrupt 2. */
235      mipsnet_init(0x4200, env->irq[2]);
236  }
237  
238  static void mips_mipssim_machine_init(MachineClass *mc)
239  {
240      mc->desc = "MIPS MIPSsim platform";
241      mc->init = mips_mipssim_init;
242  #ifdef TARGET_MIPS64
243      mc->default_cpu_type = MIPS_CPU_TYPE_NAME("5Kf");
244  #else
245      mc->default_cpu_type = MIPS_CPU_TYPE_NAME("24Kf");
246  #endif
247      mc->default_ram_id = "mips_mipssim.ram";
248  }
249  
250  DEFINE_MACHINE("mipssim", mips_mipssim_machine_init)
251