xref: /qemu/hw/arm/microbit.c (revision bb6c8d40)
1 /*
2  * BBC micro:bit machine
3  * http://tech.microbit.org/hardware/
4  *
5  * Copyright 2018 Joel Stanley <joel@jms.id.au>
6  *
7  * This code is licensed under the GPL version 2 or later.  See
8  * the COPYING file in the top-level directory.
9  */
10 
11 #include "qemu/osdep.h"
12 #include "qapi/error.h"
13 #include "hw/boards.h"
14 #include "hw/arm/arm.h"
15 #include "sysemu/sysemu.h"
16 #include "exec/address-spaces.h"
17 
18 #include "hw/arm/nrf51_soc.h"
19 #include "hw/i2c/microbit_i2c.h"
20 
21 typedef struct {
22     MachineState parent;
23 
24     NRF51State nrf51;
25     MicrobitI2CState i2c;
26 } MicrobitMachineState;
27 
28 #define TYPE_MICROBIT_MACHINE MACHINE_TYPE_NAME("microbit")
29 
30 #define MICROBIT_MACHINE(obj) \
31     OBJECT_CHECK(MicrobitMachineState, obj, TYPE_MICROBIT_MACHINE)
32 
33 static void microbit_init(MachineState *machine)
34 {
35     MicrobitMachineState *s = MICROBIT_MACHINE(machine);
36     MemoryRegion *system_memory = get_system_memory();
37     MemoryRegion *mr;
38     Object *soc = OBJECT(&s->nrf51);
39     Object *i2c = OBJECT(&s->i2c);
40 
41     sysbus_init_child_obj(OBJECT(machine), "nrf51", soc, sizeof(s->nrf51),
42                           TYPE_NRF51_SOC);
43     qdev_prop_set_chr(DEVICE(&s->nrf51), "serial0", serial_hd(0));
44     object_property_set_link(soc, OBJECT(system_memory), "memory",
45                              &error_fatal);
46     object_property_set_bool(soc, true, "realized", &error_fatal);
47 
48     /*
49      * Overlap the TWI stub device into the SoC.  This is a microbit-specific
50      * hack until we implement the nRF51 TWI controller properly and the
51      * magnetometer/accelerometer devices.
52      */
53     sysbus_init_child_obj(OBJECT(machine), "microbit.twi", i2c,
54                           sizeof(s->i2c), TYPE_MICROBIT_I2C);
55     object_property_set_bool(i2c, true, "realized", &error_fatal);
56     mr = sysbus_mmio_get_region(SYS_BUS_DEVICE(i2c), 0);
57     memory_region_add_subregion_overlap(&s->nrf51.container, NRF51_TWI_BASE,
58                                         mr, -1);
59 
60     armv7m_load_kernel(ARM_CPU(first_cpu), machine->kernel_filename,
61                        NRF51_SOC(soc)->flash_size);
62 }
63 
64 static void microbit_machine_class_init(ObjectClass *oc, void *data)
65 {
66     MachineClass *mc = MACHINE_CLASS(oc);
67 
68     mc->desc = "BBC micro:bit";
69     mc->init = microbit_init;
70     mc->max_cpus = 1;
71 }
72 
73 static const TypeInfo microbit_info = {
74     .name = TYPE_MICROBIT_MACHINE,
75     .parent = TYPE_MACHINE,
76     .instance_size = sizeof(MicrobitMachineState),
77     .class_init = microbit_machine_class_init,
78 };
79 
80 static void microbit_machine_init(void)
81 {
82     type_register_static(&microbit_info);
83 }
84 
85 type_init(microbit_machine_init);
86