hw/arm/microbit.c

   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 #include "qom/object.h"
  22
  23 struct MicrobitMachineState {
  24     MachineState parent;
  25
  26     NRF51State nrf51;
  27     MicrobitI2CState i2c;
  28 };
  29
  30 #define TYPE_MICROBIT_MACHINE MACHINE_TYPE_NAME("microbit")
  31
  32 OBJECT_DECLARE_SIMPLE_TYPE(MicrobitMachineState, 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 (Cortex-M0)";
  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);