LXR qemu/include/hw/char/avr

   1/*
   2 * AVR USART
   3 *
   4 * Copyright (c) 2018 University of Kent
   5 * Author: Sarah Harris
   6 *
   7 * This library is free software; you can redistribute it and/or
   8 * modify it under the terms of the GNU Lesser General Public
   9 * License as published by the Free Software Foundation; either
  10 * version 2.1 of the License, or (at your option) any later version.
  11 *
  12 * This library is distributed in the hope that it will be useful,
  13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 * Lesser General Public License for more details.
  16 *
  17 * You should have received a copy of the GNU Lesser General Public
  18 * License along with this library; if not, see
  19 * <http://www.gnu.org/licenses/lgpl-2.1.html>
  20 */
  21
  22#ifndef HW_CHAR_AVR_USART_H
  23#define HW_CHAR_AVR_USART_H
  24
  25#include "hw/sysbus.h"
  26#include "chardev/char-fe.h"
  27#include "hw/hw.h"
  28
  29/* Offsets of registers. */
  30#define USART_DR   0x06
  31#define USART_CSRA  0x00
  32#define USART_CSRB  0x01
  33#define USART_CSRC  0x02
  34#define USART_BRRH 0x05
  35#define USART_BRRL 0x04
  36
  37/* Relevant bits in regiters. */
  38#define USART_CSRA_RXC    (1 << 7)
  39#define USART_CSRA_TXC    (1 << 6)
  40#define USART_CSRA_DRE    (1 << 5)
  41#define USART_CSRA_MPCM   (1 << 0)
  42
  43#define USART_CSRB_RXCIE  (1 << 7)
  44#define USART_CSRB_TXCIE  (1 << 6)
  45#define USART_CSRB_DREIE  (1 << 5)
  46#define USART_CSRB_RXEN   (1 << 4)
  47#define USART_CSRB_TXEN   (1 << 3)
  48#define USART_CSRB_CSZ2   (1 << 2)
  49#define USART_CSRB_RXB8   (1 << 1)
  50#define USART_CSRB_TXB8   (1 << 0)
  51
  52#define USART_CSRC_MSEL1  (1 << 7)
  53#define USART_CSRC_MSEL0  (1 << 6)
  54#define USART_CSRC_PM1    (1 << 5)
  55#define USART_CSRC_PM0    (1 << 4)
  56#define USART_CSRC_CSZ1   (1 << 2)
  57#define USART_CSRC_CSZ0   (1 << 1)
  58
  59#define TYPE_AVR_USART "avr-usart"
  60#define AVR_USART(obj) \
  61    OBJECT_CHECK(AVRUsartState, (obj), TYPE_AVR_USART)
  62
  63typedef struct {
  64    /* <private> */
  65    SysBusDevice parent_obj;
  66
  67    /* <public> */
  68    MemoryRegion mmio;
  69
  70    CharBackend chr;
  71
  72    bool enabled;
  73
  74    uint8_t data;
  75    bool data_valid;
  76    uint8_t char_mask;
  77    /* Control and Status Registers */
  78    uint8_t csra;
  79    uint8_t csrb;
  80    uint8_t csrc;
  81    /* Baud Rate Registers (low/high byte) */
  82    uint8_t brrh;
  83    uint8_t brrl;
  84
  85    /* Receive Complete */
  86    qemu_irq rxc_irq;
  87    /* Transmit Complete */
  88    qemu_irq txc_irq;
  89    /* Data Register Empty */
  90    qemu_irq dre_irq;
  91} AVRUsartState;
  92
  93#endif /* HW_CHAR_AVR_USART_H */
  94