xref: /openbmc/qemu/hw/ppc/prep.c (revision 1fd6bb44)
1 /*
2  * QEMU PPC PREP hardware System Emulator
3  *
4  * Copyright (c) 2003-2007 Jocelyn Mayer
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include "hw/hw.h"
25 #include "hw/timer/m48t59.h"
26 #include "hw/i386/pc.h"
27 #include "hw/char/serial.h"
28 #include "hw/block/fdc.h"
29 #include "net/net.h"
30 #include "sysemu/sysemu.h"
31 #include "hw/isa/isa.h"
32 #include "hw/pci/pci.h"
33 #include "hw/pci/pci_host.h"
34 #include "hw/ppc/ppc.h"
35 #include "hw/boards.h"
36 #include "qemu/log.h"
37 #include "hw/ide.h"
38 #include "hw/loader.h"
39 #include "hw/timer/mc146818rtc.h"
40 #include "hw/isa/pc87312.h"
41 #include "sysemu/blockdev.h"
42 #include "sysemu/arch_init.h"
43 #include "exec/address-spaces.h"
44 
45 //#define HARD_DEBUG_PPC_IO
46 //#define DEBUG_PPC_IO
47 
48 /* SMP is not enabled, for now */
49 #define MAX_CPUS 1
50 
51 #define MAX_IDE_BUS 2
52 
53 #define BIOS_SIZE (1024 * 1024)
54 #define BIOS_FILENAME "ppc_rom.bin"
55 #define KERNEL_LOAD_ADDR 0x01000000
56 #define INITRD_LOAD_ADDR 0x01800000
57 
58 #if defined (HARD_DEBUG_PPC_IO) && !defined (DEBUG_PPC_IO)
59 #define DEBUG_PPC_IO
60 #endif
61 
62 #if defined (HARD_DEBUG_PPC_IO)
63 #define PPC_IO_DPRINTF(fmt, ...)                         \
64 do {                                                     \
65     if (qemu_loglevel_mask(CPU_LOG_IOPORT)) {            \
66         qemu_log("%s: " fmt, __func__ , ## __VA_ARGS__); \
67     } else {                                             \
68         printf("%s : " fmt, __func__ , ## __VA_ARGS__);  \
69     }                                                    \
70 } while (0)
71 #elif defined (DEBUG_PPC_IO)
72 #define PPC_IO_DPRINTF(fmt, ...) \
73 qemu_log_mask(CPU_LOG_IOPORT, fmt, ## __VA_ARGS__)
74 #else
75 #define PPC_IO_DPRINTF(fmt, ...) do { } while (0)
76 #endif
77 
78 /* Constants for devices init */
79 static const int ide_iobase[2] = { 0x1f0, 0x170 };
80 static const int ide_iobase2[2] = { 0x3f6, 0x376 };
81 static const int ide_irq[2] = { 13, 13 };
82 
83 #define NE2000_NB_MAX 6
84 
85 static uint32_t ne2000_io[NE2000_NB_MAX] = { 0x300, 0x320, 0x340, 0x360, 0x280, 0x380 };
86 static int ne2000_irq[NE2000_NB_MAX] = { 9, 10, 11, 3, 4, 5 };
87 
88 /* ISA IO ports bridge */
89 #define PPC_IO_BASE 0x80000000
90 
91 /* PowerPC control and status registers */
92 #if 0 // Not used
93 static struct {
94     /* IDs */
95     uint32_t veni_devi;
96     uint32_t revi;
97     /* Control and status */
98     uint32_t gcsr;
99     uint32_t xcfr;
100     uint32_t ct32;
101     uint32_t mcsr;
102     /* General purpose registers */
103     uint32_t gprg[6];
104     /* Exceptions */
105     uint32_t feen;
106     uint32_t fest;
107     uint32_t fema;
108     uint32_t fecl;
109     uint32_t eeen;
110     uint32_t eest;
111     uint32_t eecl;
112     uint32_t eeint;
113     uint32_t eemck0;
114     uint32_t eemck1;
115     /* Error diagnostic */
116 } XCSR;
117 
118 static void PPC_XCSR_writeb (void *opaque,
119                              hwaddr addr, uint32_t value)
120 {
121     printf("%s: 0x" TARGET_FMT_plx " => 0x%08" PRIx32 "\n", __func__, addr,
122            value);
123 }
124 
125 static void PPC_XCSR_writew (void *opaque,
126                              hwaddr addr, uint32_t value)
127 {
128     printf("%s: 0x" TARGET_FMT_plx " => 0x%08" PRIx32 "\n", __func__, addr,
129            value);
130 }
131 
132 static void PPC_XCSR_writel (void *opaque,
133                              hwaddr addr, uint32_t value)
134 {
135     printf("%s: 0x" TARGET_FMT_plx " => 0x%08" PRIx32 "\n", __func__, addr,
136            value);
137 }
138 
139 static uint32_t PPC_XCSR_readb (void *opaque, hwaddr addr)
140 {
141     uint32_t retval = 0;
142 
143     printf("%s: 0x" TARGET_FMT_plx " <= %08" PRIx32 "\n", __func__, addr,
144            retval);
145 
146     return retval;
147 }
148 
149 static uint32_t PPC_XCSR_readw (void *opaque, hwaddr addr)
150 {
151     uint32_t retval = 0;
152 
153     printf("%s: 0x" TARGET_FMT_plx " <= %08" PRIx32 "\n", __func__, addr,
154            retval);
155 
156     return retval;
157 }
158 
159 static uint32_t PPC_XCSR_readl (void *opaque, hwaddr addr)
160 {
161     uint32_t retval = 0;
162 
163     printf("%s: 0x" TARGET_FMT_plx " <= %08" PRIx32 "\n", __func__, addr,
164            retval);
165 
166     return retval;
167 }
168 
169 static const MemoryRegionOps PPC_XCSR_ops = {
170     .old_mmio = {
171         .read = { PPC_XCSR_readb, PPC_XCSR_readw, PPC_XCSR_readl, },
172         .write = { PPC_XCSR_writeb, PPC_XCSR_writew, PPC_XCSR_writel, },
173     },
174     .endianness = DEVICE_LITTLE_ENDIAN,
175 };
176 
177 #endif
178 
179 /* Fake super-io ports for PREP platform (Intel 82378ZB) */
180 typedef struct sysctrl_t {
181     qemu_irq reset_irq;
182     M48t59State *nvram;
183     uint8_t state;
184     uint8_t syscontrol;
185     int contiguous_map;
186     int endian;
187 } sysctrl_t;
188 
189 enum {
190     STATE_HARDFILE = 0x01,
191 };
192 
193 static sysctrl_t *sysctrl;
194 
195 static void PREP_io_800_writeb (void *opaque, uint32_t addr, uint32_t val)
196 {
197     sysctrl_t *sysctrl = opaque;
198 
199     PPC_IO_DPRINTF("0x%08" PRIx32 " => 0x%02" PRIx32 "\n",
200                    addr - PPC_IO_BASE, val);
201     switch (addr) {
202     case 0x0092:
203         /* Special port 92 */
204         /* Check soft reset asked */
205         if (val & 0x01) {
206             qemu_irq_raise(sysctrl->reset_irq);
207         } else {
208             qemu_irq_lower(sysctrl->reset_irq);
209         }
210         /* Check LE mode */
211         if (val & 0x02) {
212             sysctrl->endian = 1;
213         } else {
214             sysctrl->endian = 0;
215         }
216         break;
217     case 0x0800:
218         /* Motorola CPU configuration register : read-only */
219         break;
220     case 0x0802:
221         /* Motorola base module feature register : read-only */
222         break;
223     case 0x0803:
224         /* Motorola base module status register : read-only */
225         break;
226     case 0x0808:
227         /* Hardfile light register */
228         if (val & 1)
229             sysctrl->state |= STATE_HARDFILE;
230         else
231             sysctrl->state &= ~STATE_HARDFILE;
232         break;
233     case 0x0810:
234         /* Password protect 1 register */
235         if (sysctrl->nvram != NULL)
236             m48t59_toggle_lock(sysctrl->nvram, 1);
237         break;
238     case 0x0812:
239         /* Password protect 2 register */
240         if (sysctrl->nvram != NULL)
241             m48t59_toggle_lock(sysctrl->nvram, 2);
242         break;
243     case 0x0814:
244         /* L2 invalidate register */
245         //        tlb_flush(first_cpu, 1);
246         break;
247     case 0x081C:
248         /* system control register */
249         sysctrl->syscontrol = val & 0x0F;
250         break;
251     case 0x0850:
252         /* I/O map type register */
253         sysctrl->contiguous_map = val & 0x01;
254         break;
255     default:
256         printf("ERROR: unaffected IO port write: %04" PRIx32
257                " => %02" PRIx32"\n", addr, val);
258         break;
259     }
260 }
261 
262 static uint32_t PREP_io_800_readb (void *opaque, uint32_t addr)
263 {
264     sysctrl_t *sysctrl = opaque;
265     uint32_t retval = 0xFF;
266 
267     switch (addr) {
268     case 0x0092:
269         /* Special port 92 */
270         retval = 0x00;
271         break;
272     case 0x0800:
273         /* Motorola CPU configuration register */
274         retval = 0xEF; /* MPC750 */
275         break;
276     case 0x0802:
277         /* Motorola Base module feature register */
278         retval = 0xAD; /* No ESCC, PMC slot neither ethernet */
279         break;
280     case 0x0803:
281         /* Motorola base module status register */
282         retval = 0xE0; /* Standard MPC750 */
283         break;
284     case 0x080C:
285         /* Equipment present register:
286          *  no L2 cache
287          *  no upgrade processor
288          *  no cards in PCI slots
289          *  SCSI fuse is bad
290          */
291         retval = 0x3C;
292         break;
293     case 0x0810:
294         /* Motorola base module extended feature register */
295         retval = 0x39; /* No USB, CF and PCI bridge. NVRAM present */
296         break;
297     case 0x0814:
298         /* L2 invalidate: don't care */
299         break;
300     case 0x0818:
301         /* Keylock */
302         retval = 0x00;
303         break;
304     case 0x081C:
305         /* system control register
306          * 7 - 6 / 1 - 0: L2 cache enable
307          */
308         retval = sysctrl->syscontrol;
309         break;
310     case 0x0823:
311         /* */
312         retval = 0x03; /* no L2 cache */
313         break;
314     case 0x0850:
315         /* I/O map type register */
316         retval = sysctrl->contiguous_map;
317         break;
318     default:
319         printf("ERROR: unaffected IO port: %04" PRIx32 " read\n", addr);
320         break;
321     }
322     PPC_IO_DPRINTF("0x%08" PRIx32 " <= 0x%02" PRIx32 "\n",
323                    addr - PPC_IO_BASE, retval);
324 
325     return retval;
326 }
327 
328 static inline hwaddr prep_IO_address(sysctrl_t *sysctrl,
329                                                  hwaddr addr)
330 {
331     if (sysctrl->contiguous_map == 0) {
332         /* 64 KB contiguous space for IOs */
333         addr &= 0xFFFF;
334     } else {
335         /* 8 MB non-contiguous space for IOs */
336         addr = (addr & 0x1F) | ((addr & 0x007FFF000) >> 7);
337     }
338 
339     return addr;
340 }
341 
342 static void PPC_prep_io_writeb (void *opaque, hwaddr addr,
343                                 uint32_t value)
344 {
345     sysctrl_t *sysctrl = opaque;
346 
347     addr = prep_IO_address(sysctrl, addr);
348     cpu_outb(addr, value);
349 }
350 
351 static uint32_t PPC_prep_io_readb (void *opaque, hwaddr addr)
352 {
353     sysctrl_t *sysctrl = opaque;
354     uint32_t ret;
355 
356     addr = prep_IO_address(sysctrl, addr);
357     ret = cpu_inb(addr);
358 
359     return ret;
360 }
361 
362 static void PPC_prep_io_writew (void *opaque, hwaddr addr,
363                                 uint32_t value)
364 {
365     sysctrl_t *sysctrl = opaque;
366 
367     addr = prep_IO_address(sysctrl, addr);
368     PPC_IO_DPRINTF("0x" TARGET_FMT_plx " => 0x%08" PRIx32 "\n", addr, value);
369     cpu_outw(addr, value);
370 }
371 
372 static uint32_t PPC_prep_io_readw (void *opaque, hwaddr addr)
373 {
374     sysctrl_t *sysctrl = opaque;
375     uint32_t ret;
376 
377     addr = prep_IO_address(sysctrl, addr);
378     ret = cpu_inw(addr);
379     PPC_IO_DPRINTF("0x" TARGET_FMT_plx " <= 0x%08" PRIx32 "\n", addr, ret);
380 
381     return ret;
382 }
383 
384 static void PPC_prep_io_writel (void *opaque, hwaddr addr,
385                                 uint32_t value)
386 {
387     sysctrl_t *sysctrl = opaque;
388 
389     addr = prep_IO_address(sysctrl, addr);
390     PPC_IO_DPRINTF("0x" TARGET_FMT_plx " => 0x%08" PRIx32 "\n", addr, value);
391     cpu_outl(addr, value);
392 }
393 
394 static uint32_t PPC_prep_io_readl (void *opaque, hwaddr addr)
395 {
396     sysctrl_t *sysctrl = opaque;
397     uint32_t ret;
398 
399     addr = prep_IO_address(sysctrl, addr);
400     ret = cpu_inl(addr);
401     PPC_IO_DPRINTF("0x" TARGET_FMT_plx " <= 0x%08" PRIx32 "\n", addr, ret);
402 
403     return ret;
404 }
405 
406 static const MemoryRegionOps PPC_prep_io_ops = {
407     .old_mmio = {
408         .read = { PPC_prep_io_readb, PPC_prep_io_readw, PPC_prep_io_readl },
409         .write = { PPC_prep_io_writeb, PPC_prep_io_writew, PPC_prep_io_writel },
410     },
411     .endianness = DEVICE_LITTLE_ENDIAN,
412 };
413 
414 #define NVRAM_SIZE        0x2000
415 
416 static void cpu_request_exit(void *opaque, int irq, int level)
417 {
418     CPUPPCState *env = cpu_single_env;
419 
420     if (env && level) {
421         cpu_exit(env);
422     }
423 }
424 
425 static void ppc_prep_reset(void *opaque)
426 {
427     PowerPCCPU *cpu = opaque;
428 
429     cpu_reset(CPU(cpu));
430 }
431 
432 /* PowerPC PREP hardware initialisation */
433 static void ppc_prep_init(QEMUMachineInitArgs *args)
434 {
435     ram_addr_t ram_size = args->ram_size;
436     const char *cpu_model = args->cpu_model;
437     const char *kernel_filename = args->kernel_filename;
438     const char *kernel_cmdline = args->kernel_cmdline;
439     const char *initrd_filename = args->initrd_filename;
440     const char *boot_device = args->boot_device;
441     MemoryRegion *sysmem = get_system_memory();
442     PowerPCCPU *cpu = NULL;
443     CPUPPCState *env = NULL;
444     char *filename;
445     nvram_t nvram;
446     M48t59State *m48t59;
447     MemoryRegion *PPC_io_memory = g_new(MemoryRegion, 1);
448 #if 0
449     MemoryRegion *xcsr = g_new(MemoryRegion, 1);
450 #endif
451     int linux_boot, i, nb_nics1, bios_size;
452     MemoryRegion *ram = g_new(MemoryRegion, 1);
453     MemoryRegion *bios = g_new(MemoryRegion, 1);
454     uint32_t kernel_base, initrd_base;
455     long kernel_size, initrd_size;
456     DeviceState *dev;
457     PCIHostState *pcihost;
458     PCIBus *pci_bus;
459     PCIDevice *pci;
460     ISABus *isa_bus;
461     ISADevice *isa;
462     qemu_irq *cpu_exit_irq;
463     int ppc_boot_device;
464     DriveInfo *hd[MAX_IDE_BUS * MAX_IDE_DEVS];
465 
466     sysctrl = g_malloc0(sizeof(sysctrl_t));
467 
468     linux_boot = (kernel_filename != NULL);
469 
470     /* init CPUs */
471     if (cpu_model == NULL)
472         cpu_model = "602";
473     for (i = 0; i < smp_cpus; i++) {
474         cpu = cpu_ppc_init(cpu_model);
475         if (cpu == NULL) {
476             fprintf(stderr, "Unable to find PowerPC CPU definition\n");
477             exit(1);
478         }
479         env = &cpu->env;
480 
481         if (env->flags & POWERPC_FLAG_RTC_CLK) {
482             /* POWER / PowerPC 601 RTC clock frequency is 7.8125 MHz */
483             cpu_ppc_tb_init(env, 7812500UL);
484         } else {
485             /* Set time-base frequency to 100 Mhz */
486             cpu_ppc_tb_init(env, 100UL * 1000UL * 1000UL);
487         }
488         qemu_register_reset(ppc_prep_reset, cpu);
489     }
490 
491     /* allocate RAM */
492     memory_region_init_ram(ram, "ppc_prep.ram", ram_size);
493     vmstate_register_ram_global(ram);
494     memory_region_add_subregion(sysmem, 0, ram);
495 
496     /* allocate and load BIOS */
497     memory_region_init_ram(bios, "ppc_prep.bios", BIOS_SIZE);
498     memory_region_set_readonly(bios, true);
499     memory_region_add_subregion(sysmem, (uint32_t)(-BIOS_SIZE), bios);
500     vmstate_register_ram_global(bios);
501     if (bios_name == NULL)
502         bios_name = BIOS_FILENAME;
503     filename = qemu_find_file(QEMU_FILE_TYPE_BIOS, bios_name);
504     if (filename) {
505         bios_size = get_image_size(filename);
506     } else {
507         bios_size = -1;
508     }
509     if (bios_size > 0 && bios_size <= BIOS_SIZE) {
510         hwaddr bios_addr;
511         bios_size = (bios_size + 0xfff) & ~0xfff;
512         bios_addr = (uint32_t)(-bios_size);
513         bios_size = load_image_targphys(filename, bios_addr, bios_size);
514     }
515     if (bios_size < 0 || bios_size > BIOS_SIZE) {
516         hw_error("qemu: could not load PPC PREP bios '%s'\n", bios_name);
517     }
518     if (filename) {
519         g_free(filename);
520     }
521 
522     if (linux_boot) {
523         kernel_base = KERNEL_LOAD_ADDR;
524         /* now we can load the kernel */
525         kernel_size = load_image_targphys(kernel_filename, kernel_base,
526                                           ram_size - kernel_base);
527         if (kernel_size < 0) {
528             hw_error("qemu: could not load kernel '%s'\n", kernel_filename);
529             exit(1);
530         }
531         /* load initrd */
532         if (initrd_filename) {
533             initrd_base = INITRD_LOAD_ADDR;
534             initrd_size = load_image_targphys(initrd_filename, initrd_base,
535                                               ram_size - initrd_base);
536             if (initrd_size < 0) {
537                 hw_error("qemu: could not load initial ram disk '%s'\n",
538                           initrd_filename);
539             }
540         } else {
541             initrd_base = 0;
542             initrd_size = 0;
543         }
544         ppc_boot_device = 'm';
545     } else {
546         kernel_base = 0;
547         kernel_size = 0;
548         initrd_base = 0;
549         initrd_size = 0;
550         ppc_boot_device = '\0';
551         /* For now, OHW cannot boot from the network. */
552         for (i = 0; boot_device[i] != '\0'; i++) {
553             if (boot_device[i] >= 'a' && boot_device[i] <= 'f') {
554                 ppc_boot_device = boot_device[i];
555                 break;
556             }
557         }
558         if (ppc_boot_device == '\0') {
559             fprintf(stderr, "No valid boot device for Mac99 machine\n");
560             exit(1);
561         }
562     }
563 
564     if (PPC_INPUT(env) != PPC_FLAGS_INPUT_6xx) {
565         hw_error("Only 6xx bus is supported on PREP machine\n");
566     }
567 
568     dev = qdev_create(NULL, "raven-pcihost");
569     pcihost = PCI_HOST_BRIDGE(dev);
570     object_property_add_child(qdev_get_machine(), "raven", OBJECT(dev), NULL);
571     qdev_init_nofail(dev);
572     pci_bus = (PCIBus *)qdev_get_child_bus(dev, "pci.0");
573     if (pci_bus == NULL) {
574         fprintf(stderr, "Couldn't create PCI host controller.\n");
575         exit(1);
576     }
577 
578     /* PCI -> ISA bridge */
579     pci = pci_create_simple(pci_bus, PCI_DEVFN(1, 0), "i82378");
580     cpu_exit_irq = qemu_allocate_irqs(cpu_request_exit, NULL, 1);
581     qdev_connect_gpio_out(&pci->qdev, 0,
582                           first_cpu->irq_inputs[PPC6xx_INPUT_INT]);
583     qdev_connect_gpio_out(&pci->qdev, 1, *cpu_exit_irq);
584     sysbus_connect_irq(&pcihost->busdev, 0, qdev_get_gpio_in(&pci->qdev, 9));
585     sysbus_connect_irq(&pcihost->busdev, 1, qdev_get_gpio_in(&pci->qdev, 11));
586     sysbus_connect_irq(&pcihost->busdev, 2, qdev_get_gpio_in(&pci->qdev, 9));
587     sysbus_connect_irq(&pcihost->busdev, 3, qdev_get_gpio_in(&pci->qdev, 11));
588     isa_bus = DO_UPCAST(ISABus, qbus, qdev_get_child_bus(&pci->qdev, "isa.0"));
589 
590     /* Super I/O (parallel + serial ports) */
591     isa = isa_create(isa_bus, TYPE_PC87312);
592     qdev_prop_set_uint8(&isa->qdev, "config", 13); /* fdc, ser0, ser1, par0 */
593     qdev_init_nofail(&isa->qdev);
594 
595     /* Register 8 MB of ISA IO space (needed for non-contiguous map) */
596     memory_region_init_io(PPC_io_memory, &PPC_prep_io_ops, sysctrl,
597                           "ppc-io", 0x00800000);
598     memory_region_add_subregion(sysmem, 0x80000000, PPC_io_memory);
599 
600     /* init basic PC hardware */
601     pci_vga_init(pci_bus);
602 
603     nb_nics1 = nb_nics;
604     if (nb_nics1 > NE2000_NB_MAX)
605         nb_nics1 = NE2000_NB_MAX;
606     for(i = 0; i < nb_nics1; i++) {
607         if (nd_table[i].model == NULL) {
608 	    nd_table[i].model = g_strdup("ne2k_isa");
609         }
610         if (strcmp(nd_table[i].model, "ne2k_isa") == 0) {
611             isa_ne2000_init(isa_bus, ne2000_io[i], ne2000_irq[i],
612                             &nd_table[i]);
613         } else {
614             pci_nic_init_nofail(&nd_table[i], "ne2k_pci", NULL);
615         }
616     }
617 
618     ide_drive_get(hd, MAX_IDE_BUS);
619     for(i = 0; i < MAX_IDE_BUS; i++) {
620         isa_ide_init(isa_bus, ide_iobase[i], ide_iobase2[i], ide_irq[i],
621                      hd[2 * i],
622 		     hd[2 * i + 1]);
623     }
624     isa_create_simple(isa_bus, "i8042");
625 
626     sysctrl->reset_irq = first_cpu->irq_inputs[PPC6xx_INPUT_HRESET];
627     /* System control ports */
628     register_ioport_read(0x0092, 0x01, 1, &PREP_io_800_readb, sysctrl);
629     register_ioport_write(0x0092, 0x01, 1, &PREP_io_800_writeb, sysctrl);
630     register_ioport_read(0x0800, 0x52, 1, &PREP_io_800_readb, sysctrl);
631     register_ioport_write(0x0800, 0x52, 1, &PREP_io_800_writeb, sysctrl);
632     /* PowerPC control and status register group */
633 #if 0
634     memory_region_init_io(xcsr, &PPC_XCSR_ops, NULL, "ppc-xcsr", 0x1000);
635     memory_region_add_subregion(sysmem, 0xFEFF0000, xcsr);
636 #endif
637 
638     if (usb_enabled(false)) {
639         pci_create_simple(pci_bus, -1, "pci-ohci");
640     }
641 
642     m48t59 = m48t59_init_isa(isa_bus, 0x0074, NVRAM_SIZE, 59);
643     if (m48t59 == NULL)
644         return;
645     sysctrl->nvram = m48t59;
646 
647     /* Initialise NVRAM */
648     nvram.opaque = m48t59;
649     nvram.read_fn = &m48t59_read;
650     nvram.write_fn = &m48t59_write;
651     PPC_NVRAM_set_params(&nvram, NVRAM_SIZE, "PREP", ram_size, ppc_boot_device,
652                          kernel_base, kernel_size,
653                          kernel_cmdline,
654                          initrd_base, initrd_size,
655                          /* XXX: need an option to load a NVRAM image */
656                          0,
657                          graphic_width, graphic_height, graphic_depth);
658 
659     /* Special port to get debug messages from Open-Firmware */
660     register_ioport_write(0x0F00, 4, 1, &PPC_debug_write, NULL);
661 
662     /* Initialize audio subsystem */
663     audio_init(isa_bus, pci_bus);
664 }
665 
666 static QEMUMachine prep_machine = {
667     .name = "prep",
668     .desc = "PowerPC PREP platform",
669     .init = ppc_prep_init,
670     .max_cpus = MAX_CPUS,
671     DEFAULT_MACHINE_OPTIONS,
672 };
673 
674 static void prep_machine_init(void)
675 {
676     qemu_register_machine(&prep_machine);
677 }
678 
679 machine_init(prep_machine_init);
680