xref: /openbmc/qemu/hw/arm/microbit.c (revision 7acafcfa)
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/boot.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 #include "hw/qdev-properties.h"
21 
22 typedef struct {
23     MachineState parent;
24 
25     NRF51State nrf51;
26     MicrobitI2CState i2c;
27 } MicrobitMachineState;
28 
29 #define TYPE_MICROBIT_MACHINE MACHINE_TYPE_NAME("microbit")
30 
31 #define MICROBIT_MACHINE(obj) \
32     OBJECT_CHECK(MicrobitMachineState, obj, TYPE_MICROBIT_MACHINE)
33 
34 static void microbit_init(MachineState *machine)
35 {
36     MicrobitMachineState *s = MICROBIT_MACHINE(machine);
37     MemoryRegion *system_memory = get_system_memory();
38     MemoryRegion *mr;
39 
40     object_initialize_child(OBJECT(machine), "nrf51", &s->nrf51,
41                             TYPE_NRF51_SOC);
42     qdev_prop_set_chr(DEVICE(&s->nrf51), "serial0", serial_hd(0));
43     object_property_set_link(OBJECT(&s->nrf51), "memory",
44                              OBJECT(system_memory), &error_fatal);
45     sysbus_realize(SYS_BUS_DEVICE(&s->nrf51), &error_fatal);
46 
47     /*
48      * Overlap the TWI stub device into the SoC.  This is a microbit-specific
49      * hack until we implement the nRF51 TWI controller properly and the
50      * magnetometer/accelerometer devices.
51      */
52     object_initialize_child(OBJECT(machine), "microbit.twi", &s->i2c,
53                             TYPE_MICROBIT_I2C);
54     sysbus_realize(SYS_BUS_DEVICE(&s->i2c), &error_fatal);
55     mr = sysbus_mmio_get_region(SYS_BUS_DEVICE(&s->i2c), 0);
56     memory_region_add_subregion_overlap(&s->nrf51.container, NRF51_TWI_BASE,
57                                         mr, -1);
58 
59     armv7m_load_kernel(ARM_CPU(first_cpu), machine->kernel_filename,
60                        s->nrf51.flash_size);
61 }
62 
63 static void microbit_machine_class_init(ObjectClass *oc, void *data)
64 {
65     MachineClass *mc = MACHINE_CLASS(oc);
66 
67     mc->desc = "BBC micro:bit";
68     mc->init = microbit_init;
69     mc->max_cpus = 1;
70 }
71 
72 static const TypeInfo microbit_info = {
73     .name = TYPE_MICROBIT_MACHINE,
74     .parent = TYPE_MACHINE,
75     .instance_size = sizeof(MicrobitMachineState),
76     .class_init = microbit_machine_class_init,
77 };
78 
79 static void microbit_machine_init(void)
80 {
81     type_register_static(&microbit_info);
82 }
83 
84 type_init(microbit_machine_init);
85