include/hw/i2c/microbit_i2c.h

   1 /*
   2  * Microbit stub for Nordic Semiconductor nRF51 SoC Two-Wire Interface
   3  * http://infocenter.nordicsemi.com/pdf/nRF51_RM_v3.0.1.pdf
   4  *
   5  * Copyright 2019 Red Hat, Inc.
   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 #ifndef MICROBIT_I2C_H
  12 #define MICROBIT_I2C_H
  13
  14 #include "hw/sysbus.h"
  15 #include "hw/arm/nrf51.h"
  16
  17 #define NRF51_TWI_TASK_STARTRX 0x000
  18 #define NRF51_TWI_TASK_STARTTX 0x008
  19 #define NRF51_TWI_TASK_STOP 0x014
  20 #define NRF51_TWI_EVENT_STOPPED 0x104
  21 #define NRF51_TWI_EVENT_RXDREADY 0x108
  22 #define NRF51_TWI_EVENT_TXDSENT 0x11c
  23 #define NRF51_TWI_REG_ENABLE 0x500
  24 #define NRF51_TWI_REG_RXD 0x518
  25 #define NRF51_TWI_REG_TXD 0x51c
  26 #define NRF51_TWI_REG_ADDRESS 0x588
  27
  28 #define TYPE_MICROBIT_I2C "microbit.i2c"
  29 #define MICROBIT_I2C(obj) \
  30     OBJECT_CHECK(MicrobitI2CState, (obj), TYPE_MICROBIT_I2C)
  31
  32 #define MICROBIT_I2C_NREGS (NRF51_TWI_SIZE / sizeof(uint32_t))
  33
  34 typedef struct {
  35     SysBusDevice parent_obj;
  36
  37     MemoryRegion iomem;
  38     uint32_t regs[MICROBIT_I2C_NREGS];
  39     uint32_t read_idx;
  40 } MicrobitI2CState;
  41
  42 #endif /* MICROBIT_I2C_H */