xref: /qemu/hw/arm/mps3r.c (revision 0482e76289f8a5fc70f87e5be799c72853fac11a)
1 /*
2  * Arm MPS3 board emulation for Cortex-R-based FPGA images.
3  * (For M-profile images see mps2.c and mps2tz.c.)
4  *
5  * Copyright (c) 2017 Linaro Limited
6  * Written by Peter Maydell
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License version 2 or
10  *  (at your option) any later version.
11  */
12 
13 /*
14  * The MPS3 is an FPGA based dev board. This file handles FPGA images
15  * which use the Cortex-R CPUs. We model these separately from the
16  * M-profile images, because on M-profile the FPGA image is based on
17  * a "Subsystem for Embedded" which is similar to an SoC, whereas
18  * the R-profile FPGA images don't have that abstraction layer.
19  *
20  * We model the following FPGA images here:
21  *  "mps3-an536" -- dual Cortex-R52 as documented in Arm Application Note AN536
22  *
23  * Application Note AN536:
24  * https://developer.arm.com/documentation/dai0536/latest/
25  */
26 
27 #include "qemu/osdep.h"
28 #include "qemu/units.h"
29 #include "qapi/error.h"
30 #include "qapi/qmp/qlist.h"
31 #include "exec/address-spaces.h"
32 #include "cpu.h"
33 #include "sysemu/sysemu.h"
34 #include "hw/boards.h"
35 #include "hw/or-irq.h"
36 #include "hw/qdev-clock.h"
37 #include "hw/qdev-properties.h"
38 #include "hw/arm/boot.h"
39 #include "hw/arm/bsa.h"
40 #include "hw/char/cmsdk-apb-uart.h"
41 #include "hw/i2c/arm_sbcon_i2c.h"
42 #include "hw/intc/arm_gicv3.h"
43 #include "hw/misc/unimp.h"
44 #include "hw/timer/cmsdk-apb-dualtimer.h"
45 #include "hw/watchdog/cmsdk-apb-watchdog.h"
46 
47 /* Define the layout of RAM and ROM in a board */
48 typedef struct RAMInfo {
49     const char *name;
50     hwaddr base;
51     hwaddr size;
52     int mrindex; /* index into rams[]; -1 for the system RAM block */
53     int flags;
54 } RAMInfo;
55 
56 /*
57  * The MPS3 DDR is 3GiB, but on a 32-bit host QEMU doesn't permit
58  * emulation of that much guest RAM, so artificially make it smaller.
59  */
60 #if HOST_LONG_BITS == 32
61 #define MPS3_DDR_SIZE (1 * GiB)
62 #else
63 #define MPS3_DDR_SIZE (3 * GiB)
64 #endif
65 
66 /*
67  * Flag values:
68  * IS_MAIN: this is the main machine RAM
69  * IS_ROM: this area is read-only
70  */
71 #define IS_MAIN 1
72 #define IS_ROM 2
73 
74 #define MPS3R_RAM_MAX 9
75 #define MPS3R_CPU_MAX 2
76 #define MPS3R_UART_MAX 4 /* shared UART count */
77 
78 #define PERIPHBASE 0xf0000000
79 #define NUM_SPIS 96
80 
81 typedef enum MPS3RFPGAType {
82     FPGA_AN536,
83 } MPS3RFPGAType;
84 
85 struct MPS3RMachineClass {
86     MachineClass parent;
87     MPS3RFPGAType fpga_type;
88     const RAMInfo *raminfo;
89     hwaddr loader_start;
90 };
91 
92 struct MPS3RMachineState {
93     MachineState parent;
94     struct arm_boot_info bootinfo;
95     MemoryRegion ram[MPS3R_RAM_MAX];
96     Object *cpu[MPS3R_CPU_MAX];
97     MemoryRegion cpu_sysmem[MPS3R_CPU_MAX];
98     MemoryRegion sysmem_alias[MPS3R_CPU_MAX];
99     MemoryRegion cpu_ram[MPS3R_CPU_MAX];
100     GICv3State gic;
101     /* per-CPU UARTs followed by the shared UARTs */
102     CMSDKAPBUART uart[MPS3R_CPU_MAX + MPS3R_UART_MAX];
103     OrIRQState cpu_uart_oflow[MPS3R_CPU_MAX];
104     OrIRQState uart_oflow;
105     CMSDKAPBWatchdog watchdog;
106     CMSDKAPBDualTimer dualtimer;
107     ArmSbconI2CState i2c[5];
108     Clock *clk;
109 };
110 
111 #define TYPE_MPS3R_MACHINE "mps3r"
112 #define TYPE_MPS3R_AN536_MACHINE MACHINE_TYPE_NAME("mps3-an536")
113 
114 OBJECT_DECLARE_TYPE(MPS3RMachineState, MPS3RMachineClass, MPS3R_MACHINE)
115 
116 /*
117  * Main clock frequency CLK in Hz (50MHz). In the image there are also
118  * ACLK, MCLK, GPUCLK and PERIPHCLK at the same frequency; for our
119  * model we just roll them all into one.
120  */
121 #define CLK_FRQ 50000000
122 
123 static const RAMInfo an536_raminfo[] = {
124     {
125         .name = "ATCM",
126         .base = 0x00000000,
127         .size = 0x00008000,
128         .mrindex = 0,
129     }, {
130         /* We model the QSPI flash as simple ROM for now */
131         .name = "QSPI",
132         .base = 0x08000000,
133         .size = 0x00800000,
134         .flags = IS_ROM,
135         .mrindex = 1,
136     }, {
137         .name = "BRAM",
138         .base = 0x10000000,
139         .size = 0x00080000,
140         .mrindex = 2,
141     }, {
142         .name = "DDR",
143         .base = 0x20000000,
144         .size = MPS3_DDR_SIZE,
145         .mrindex = -1,
146     }, {
147         .name = "ATCM0",
148         .base = 0xee000000,
149         .size = 0x00008000,
150         .mrindex = 3,
151     }, {
152         .name = "BTCM0",
153         .base = 0xee100000,
154         .size = 0x00008000,
155         .mrindex = 4,
156     }, {
157         .name = "CTCM0",
158         .base = 0xee200000,
159         .size = 0x00008000,
160         .mrindex = 5,
161     }, {
162         .name = "ATCM1",
163         .base = 0xee400000,
164         .size = 0x00008000,
165         .mrindex = 6,
166     }, {
167         .name = "BTCM1",
168         .base = 0xee500000,
169         .size = 0x00008000,
170         .mrindex = 7,
171     }, {
172         .name = "CTCM1",
173         .base = 0xee600000,
174         .size = 0x00008000,
175         .mrindex = 8,
176     }, {
177         .name = NULL,
178     }
179 };
180 
181 static MemoryRegion *mr_for_raminfo(MPS3RMachineState *mms,
182                                     const RAMInfo *raminfo)
183 {
184     /* Return an initialized MemoryRegion for the RAMInfo. */
185     MemoryRegion *ram;
186 
187     if (raminfo->mrindex < 0) {
188         /* Means this RAMInfo is for QEMU's "system memory" */
189         MachineState *machine = MACHINE(mms);
190         assert(!(raminfo->flags & IS_ROM));
191         return machine->ram;
192     }
193 
194     assert(raminfo->mrindex < MPS3R_RAM_MAX);
195     ram = &mms->ram[raminfo->mrindex];
196 
197     memory_region_init_ram(ram, NULL, raminfo->name,
198                            raminfo->size, &error_fatal);
199     if (raminfo->flags & IS_ROM) {
200         memory_region_set_readonly(ram, true);
201     }
202     return ram;
203 }
204 
205 /*
206  * There is no defined secondary boot protocol for Linux for the AN536,
207  * because real hardware has a restriction that atomic operations between
208  * the two CPUs do not function correctly, and so true SMP is not
209  * possible. Therefore for cases where the user is directly booting
210  * a kernel, we treat the system as essentially uniprocessor, and
211  * put the secondary CPU into power-off state (as if the user on the
212  * real hardware had configured the secondary to be halted via the
213  * SCC config registers).
214  *
215  * Note that the default secondary boot code would not work here anyway
216  * as it assumes a GICv2, and we have a GICv3.
217  */
218 static void mps3r_write_secondary_boot(ARMCPU *cpu,
219                                        const struct arm_boot_info *info)
220 {
221     /*
222      * Power the secondary CPU off. This means we don't need to write any
223      * boot code into guest memory. Note that the 'cpu' argument to this
224      * function is the primary CPU we passed to arm_load_kernel(), not
225      * the secondary. Loop around all the other CPUs, as the boot.c
226      * code does for the "disable secondaries if PSCI is enabled" case.
227      */
228     for (CPUState *cs = first_cpu; cs; cs = CPU_NEXT(cs)) {
229         if (cs != first_cpu) {
230             object_property_set_bool(OBJECT(cs), "start-powered-off", true,
231                                      &error_abort);
232         }
233     }
234 }
235 
236 static void mps3r_secondary_cpu_reset(ARMCPU *cpu,
237                                       const struct arm_boot_info *info)
238 {
239     /* We don't need to do anything here because the CPU will be off */
240 }
241 
242 static void create_gic(MPS3RMachineState *mms, MemoryRegion *sysmem)
243 {
244     MachineState *machine = MACHINE(mms);
245     DeviceState *gicdev;
246     QList *redist_region_count;
247 
248     object_initialize_child(OBJECT(mms), "gic", &mms->gic, TYPE_ARM_GICV3);
249     gicdev = DEVICE(&mms->gic);
250     qdev_prop_set_uint32(gicdev, "num-cpu", machine->smp.cpus);
251     qdev_prop_set_uint32(gicdev, "num-irq", NUM_SPIS + GIC_INTERNAL);
252     redist_region_count = qlist_new();
253     qlist_append_int(redist_region_count, machine->smp.cpus);
254     qdev_prop_set_array(gicdev, "redist-region-count", redist_region_count);
255     object_property_set_link(OBJECT(&mms->gic), "sysmem",
256                              OBJECT(sysmem), &error_fatal);
257     sysbus_realize(SYS_BUS_DEVICE(&mms->gic), &error_fatal);
258     sysbus_mmio_map(SYS_BUS_DEVICE(&mms->gic), 0, PERIPHBASE);
259     sysbus_mmio_map(SYS_BUS_DEVICE(&mms->gic), 1, PERIPHBASE + 0x100000);
260     /*
261      * Wire the outputs from each CPU's generic timer and the GICv3
262      * maintenance interrupt signal to the appropriate GIC PPI inputs,
263      * and the GIC's IRQ/FIQ/VIRQ/VFIQ interrupt outputs to the CPU's inputs.
264      */
265     for (int i = 0; i < machine->smp.cpus; i++) {
266         DeviceState *cpudev = DEVICE(mms->cpu[i]);
267         SysBusDevice *gicsbd = SYS_BUS_DEVICE(&mms->gic);
268         int intidbase = NUM_SPIS + i * GIC_INTERNAL;
269         int irq;
270         /*
271          * Mapping from the output timer irq lines from the CPU to the
272          * GIC PPI inputs used for this board. This isn't a BSA board,
273          * but it uses the standard convention for the PPI numbers.
274          */
275         const int timer_irq[] = {
276             [GTIMER_PHYS] = ARCH_TIMER_NS_EL1_IRQ,
277             [GTIMER_VIRT] = ARCH_TIMER_VIRT_IRQ,
278             [GTIMER_HYP]  = ARCH_TIMER_NS_EL2_IRQ,
279         };
280 
281         for (irq = 0; irq < ARRAY_SIZE(timer_irq); irq++) {
282             qdev_connect_gpio_out(cpudev, irq,
283                                   qdev_get_gpio_in(gicdev,
284                                                    intidbase + timer_irq[irq]));
285         }
286 
287         qdev_connect_gpio_out_named(cpudev, "gicv3-maintenance-interrupt", 0,
288                                     qdev_get_gpio_in(gicdev,
289                                                      intidbase + ARCH_GIC_MAINT_IRQ));
290 
291         qdev_connect_gpio_out_named(cpudev, "pmu-interrupt", 0,
292                                     qdev_get_gpio_in(gicdev,
293                                                      intidbase + VIRTUAL_PMU_IRQ));
294 
295         sysbus_connect_irq(gicsbd, i,
296                            qdev_get_gpio_in(cpudev, ARM_CPU_IRQ));
297         sysbus_connect_irq(gicsbd, i + machine->smp.cpus,
298                            qdev_get_gpio_in(cpudev, ARM_CPU_FIQ));
299         sysbus_connect_irq(gicsbd, i + 2 * machine->smp.cpus,
300                            qdev_get_gpio_in(cpudev, ARM_CPU_VIRQ));
301         sysbus_connect_irq(gicsbd, i + 3 * machine->smp.cpus,
302                            qdev_get_gpio_in(cpudev, ARM_CPU_VFIQ));
303     }
304 }
305 
306 /*
307  * Create UART uartno, and map it into the MemoryRegion mem at address baseaddr.
308  * The qemu_irq arguments are where we connect the various IRQs from the UART.
309  */
310 static void create_uart(MPS3RMachineState *mms, int uartno, MemoryRegion *mem,
311                         hwaddr baseaddr, qemu_irq txirq, qemu_irq rxirq,
312                         qemu_irq txoverirq, qemu_irq rxoverirq,
313                         qemu_irq combirq)
314 {
315     g_autofree char *s = g_strdup_printf("uart%d", uartno);
316     SysBusDevice *sbd;
317 
318     assert(uartno < ARRAY_SIZE(mms->uart));
319     object_initialize_child(OBJECT(mms), s, &mms->uart[uartno],
320                             TYPE_CMSDK_APB_UART);
321     qdev_prop_set_uint32(DEVICE(&mms->uart[uartno]), "pclk-frq", CLK_FRQ);
322     qdev_prop_set_chr(DEVICE(&mms->uart[uartno]), "chardev", serial_hd(uartno));
323     sbd = SYS_BUS_DEVICE(&mms->uart[uartno]);
324     sysbus_realize(sbd, &error_fatal);
325     memory_region_add_subregion(mem, baseaddr,
326                                 sysbus_mmio_get_region(sbd, 0));
327     sysbus_connect_irq(sbd, 0, txirq);
328     sysbus_connect_irq(sbd, 1, rxirq);
329     sysbus_connect_irq(sbd, 2, txoverirq);
330     sysbus_connect_irq(sbd, 3, rxoverirq);
331     sysbus_connect_irq(sbd, 4, combirq);
332 }
333 
334 static void mps3r_common_init(MachineState *machine)
335 {
336     MPS3RMachineState *mms = MPS3R_MACHINE(machine);
337     MPS3RMachineClass *mmc = MPS3R_MACHINE_GET_CLASS(mms);
338     MemoryRegion *sysmem = get_system_memory();
339     DeviceState *gicdev;
340 
341     mms->clk = clock_new(OBJECT(machine), "CLK");
342     clock_set_hz(mms->clk, CLK_FRQ);
343 
344     for (const RAMInfo *ri = mmc->raminfo; ri->name; ri++) {
345         MemoryRegion *mr = mr_for_raminfo(mms, ri);
346         memory_region_add_subregion(sysmem, ri->base, mr);
347     }
348 
349     assert(machine->smp.cpus <= MPS3R_CPU_MAX);
350     for (int i = 0; i < machine->smp.cpus; i++) {
351         g_autofree char *sysmem_name = g_strdup_printf("cpu-%d-memory", i);
352         g_autofree char *ramname = g_strdup_printf("cpu-%d-memory", i);
353         g_autofree char *alias_name = g_strdup_printf("sysmem-alias-%d", i);
354 
355         /*
356          * Each CPU has some private RAM/peripherals, so create the container
357          * which will house those, with the whole-machine system memory being
358          * used where there's no CPU-specific device. Note that we need the
359          * sysmem_alias aliases because we can't put one MR (the original
360          * 'sysmem') into more than one other MR.
361          */
362         memory_region_init(&mms->cpu_sysmem[i], OBJECT(machine),
363                            sysmem_name, UINT64_MAX);
364         memory_region_init_alias(&mms->sysmem_alias[i], OBJECT(machine),
365                                  alias_name, sysmem, 0, UINT64_MAX);
366         memory_region_add_subregion_overlap(&mms->cpu_sysmem[i], 0,
367                                             &mms->sysmem_alias[i], -1);
368 
369         mms->cpu[i] = object_new(machine->cpu_type);
370         object_property_set_link(mms->cpu[i], "memory",
371                                  OBJECT(&mms->cpu_sysmem[i]), &error_abort);
372         object_property_set_int(mms->cpu[i], "reset-cbar",
373                                 PERIPHBASE, &error_abort);
374         qdev_realize(DEVICE(mms->cpu[i]), NULL, &error_fatal);
375         object_unref(mms->cpu[i]);
376 
377         /* Per-CPU RAM */
378         memory_region_init_ram(&mms->cpu_ram[i], NULL, ramname,
379                                0x1000, &error_fatal);
380         memory_region_add_subregion(&mms->cpu_sysmem[i], 0xe7c01000,
381                                     &mms->cpu_ram[i]);
382     }
383 
384     create_gic(mms, sysmem);
385     gicdev = DEVICE(&mms->gic);
386 
387     /*
388      * UARTs 0 and 1 are per-CPU; their interrupts are wired to
389      * the relevant CPU's PPI 0..3, aka INTID 16..19
390      */
391     for (int i = 0; i < machine->smp.cpus; i++) {
392         int intidbase = NUM_SPIS + i * GIC_INTERNAL;
393         g_autofree char *s = g_strdup_printf("cpu-uart-oflow-orgate%d", i);
394         DeviceState *orgate;
395 
396         /* The two overflow IRQs from the UART are ORed together into PPI 3 */
397         object_initialize_child(OBJECT(mms), s, &mms->cpu_uart_oflow[i],
398                                 TYPE_OR_IRQ);
399         orgate = DEVICE(&mms->cpu_uart_oflow[i]);
400         qdev_prop_set_uint32(orgate, "num-lines", 2);
401         qdev_realize(orgate, NULL, &error_fatal);
402         qdev_connect_gpio_out(orgate, 0,
403                               qdev_get_gpio_in(gicdev, intidbase + 19));
404 
405         create_uart(mms, i, &mms->cpu_sysmem[i], 0xe7c00000,
406                     qdev_get_gpio_in(gicdev, intidbase + 17), /* tx */
407                     qdev_get_gpio_in(gicdev, intidbase + 16), /* rx */
408                     qdev_get_gpio_in(orgate, 0), /* txover */
409                     qdev_get_gpio_in(orgate, 1), /* rxover */
410                     qdev_get_gpio_in(gicdev, intidbase + 18) /* combined */);
411     }
412     /*
413      * UARTs 2 to 5 are whole-system; all overflow IRQs are ORed
414      * together into IRQ 17
415      */
416     object_initialize_child(OBJECT(mms), "uart-oflow-orgate",
417                             &mms->uart_oflow, TYPE_OR_IRQ);
418     qdev_prop_set_uint32(DEVICE(&mms->uart_oflow), "num-lines",
419                          MPS3R_UART_MAX * 2);
420     qdev_realize(DEVICE(&mms->uart_oflow), NULL, &error_fatal);
421     qdev_connect_gpio_out(DEVICE(&mms->uart_oflow), 0,
422                           qdev_get_gpio_in(gicdev, 17));
423 
424     for (int i = 0; i < MPS3R_UART_MAX; i++) {
425         hwaddr baseaddr = 0xe0205000 + i * 0x1000;
426         int rxirq = 5 + i * 2, txirq = 6 + i * 2, combirq = 13 + i;
427 
428         create_uart(mms, i + MPS3R_CPU_MAX, sysmem, baseaddr,
429                     qdev_get_gpio_in(gicdev, txirq),
430                     qdev_get_gpio_in(gicdev, rxirq),
431                     qdev_get_gpio_in(DEVICE(&mms->uart_oflow), i * 2),
432                     qdev_get_gpio_in(DEVICE(&mms->uart_oflow), i * 2 + 1),
433                     qdev_get_gpio_in(gicdev, combirq));
434     }
435 
436     for (int i = 0; i < 4; i++) {
437         /* CMSDK GPIO controllers */
438         g_autofree char *s = g_strdup_printf("gpio%d", i);
439         create_unimplemented_device(s, 0xe0000000 + i * 0x1000, 0x1000);
440     }
441 
442     object_initialize_child(OBJECT(mms), "watchdog", &mms->watchdog,
443                             TYPE_CMSDK_APB_WATCHDOG);
444     qdev_connect_clock_in(DEVICE(&mms->watchdog), "WDOGCLK", mms->clk);
445     sysbus_realize(SYS_BUS_DEVICE(&mms->watchdog), &error_fatal);
446     sysbus_connect_irq(SYS_BUS_DEVICE(&mms->watchdog), 0,
447                        qdev_get_gpio_in(gicdev, 0));
448     sysbus_mmio_map(SYS_BUS_DEVICE(&mms->watchdog), 0, 0xe0100000);
449 
450     object_initialize_child(OBJECT(mms), "dualtimer", &mms->dualtimer,
451                             TYPE_CMSDK_APB_DUALTIMER);
452     qdev_connect_clock_in(DEVICE(&mms->dualtimer), "TIMCLK", mms->clk);
453     sysbus_realize(SYS_BUS_DEVICE(&mms->dualtimer), &error_fatal);
454     sysbus_connect_irq(SYS_BUS_DEVICE(&mms->dualtimer), 0,
455                        qdev_get_gpio_in(gicdev, 3));
456     sysbus_connect_irq(SYS_BUS_DEVICE(&mms->dualtimer), 1,
457                        qdev_get_gpio_in(gicdev, 1));
458     sysbus_connect_irq(SYS_BUS_DEVICE(&mms->dualtimer), 2,
459                        qdev_get_gpio_in(gicdev, 2));
460     sysbus_mmio_map(SYS_BUS_DEVICE(&mms->dualtimer), 0, 0xe0101000);
461 
462     for (int i = 0; i < ARRAY_SIZE(mms->i2c); i++) {
463         static const hwaddr i2cbase[] = {0xe0102000,    /* Touch */
464                                          0xe0103000,    /* Audio */
465                                          0xe0107000,    /* Shield0 */
466                                          0xe0108000,    /* Shield1 */
467                                          0xe0109000};   /* DDR4 EEPROM */
468         g_autofree char *s = g_strdup_printf("i2c%d", i);
469 
470         object_initialize_child(OBJECT(mms), s, &mms->i2c[i],
471                                 TYPE_ARM_SBCON_I2C);
472         sysbus_realize(SYS_BUS_DEVICE(&mms->i2c[i]), &error_fatal);
473         sysbus_mmio_map(SYS_BUS_DEVICE(&mms->i2c[i]), 0, i2cbase[i]);
474         if (i != 2 && i != 3) {
475             /*
476              * internal-only bus: mark it full to avoid user-created
477              * i2c devices being plugged into it.
478              */
479             qbus_mark_full(qdev_get_child_bus(DEVICE(&mms->i2c[i]), "i2c"));
480         }
481     }
482 
483     mms->bootinfo.ram_size = machine->ram_size;
484     mms->bootinfo.board_id = -1;
485     mms->bootinfo.loader_start = mmc->loader_start;
486     mms->bootinfo.write_secondary_boot = mps3r_write_secondary_boot;
487     mms->bootinfo.secondary_cpu_reset_hook = mps3r_secondary_cpu_reset;
488     arm_load_kernel(ARM_CPU(mms->cpu[0]), machine, &mms->bootinfo);
489 }
490 
491 static void mps3r_set_default_ram_info(MPS3RMachineClass *mmc)
492 {
493     /*
494      * Set mc->default_ram_size and default_ram_id from the
495      * information in mmc->raminfo.
496      */
497     MachineClass *mc = MACHINE_CLASS(mmc);
498     const RAMInfo *p;
499 
500     for (p = mmc->raminfo; p->name; p++) {
501         if (p->mrindex < 0) {
502             /* Found the entry for "system memory" */
503             mc->default_ram_size = p->size;
504             mc->default_ram_id = p->name;
505             mmc->loader_start = p->base;
506             return;
507         }
508     }
509     g_assert_not_reached();
510 }
511 
512 static void mps3r_class_init(ObjectClass *oc, void *data)
513 {
514     MachineClass *mc = MACHINE_CLASS(oc);
515 
516     mc->init = mps3r_common_init;
517 }
518 
519 static void mps3r_an536_class_init(ObjectClass *oc, void *data)
520 {
521     MachineClass *mc = MACHINE_CLASS(oc);
522     MPS3RMachineClass *mmc = MPS3R_MACHINE_CLASS(oc);
523     static const char * const valid_cpu_types[] = {
524         ARM_CPU_TYPE_NAME("cortex-r52"),
525         NULL
526     };
527 
528     mc->desc = "ARM MPS3 with AN536 FPGA image for Cortex-R52";
529     /*
530      * In the real FPGA image there are always two cores, but the standard
531      * initial setting for the SCC SYSCON 0x000 register is 0x21, meaning
532      * that the second core is held in reset and halted. Many images built for
533      * the board do not expect the second core to run at startup (especially
534      * since on the real FPGA image it is not possible to use LDREX/STREX
535      * in RAM between the two cores, so a true SMP setup isn't supported).
536      *
537      * As QEMU's equivalent of this, we support both -smp 1 and -smp 2,
538      * with the default being -smp 1. This seems a more intuitive UI for
539      * QEMU users than, for instance, having a machine property to allow
540      * the user to set the initial value of the SYSCON 0x000 register.
541      */
542     mc->default_cpus = 1;
543     mc->min_cpus = 1;
544     mc->max_cpus = 2;
545     mc->default_cpu_type = ARM_CPU_TYPE_NAME("cortex-r52");
546     mc->valid_cpu_types = valid_cpu_types;
547     mmc->raminfo = an536_raminfo;
548     mps3r_set_default_ram_info(mmc);
549 }
550 
551 static const TypeInfo mps3r_machine_types[] = {
552     {
553         .name = TYPE_MPS3R_MACHINE,
554         .parent = TYPE_MACHINE,
555         .abstract = true,
556         .instance_size = sizeof(MPS3RMachineState),
557         .class_size = sizeof(MPS3RMachineClass),
558         .class_init = mps3r_class_init,
559     }, {
560         .name = TYPE_MPS3R_AN536_MACHINE,
561         .parent = TYPE_MPS3R_MACHINE,
562         .class_init = mps3r_an536_class_init,
563     },
564 };
565 
566 DEFINE_TYPES(mps3r_machine_types);
567