include/hw/char/serial.h

   1 /*
   2  * QEMU 16550A UART emulation
   3  *
   4  * Copyright (c) 2003-2004 Fabrice Bellard
   5  * Copyright (c) 2008 Citrix Systems, Inc.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25
  26 #ifndef HW_SERIAL_H
  27 #define HW_SERIAL_H
  28
  29 #include "chardev/char-fe.h"
  30 #include "exec/memory.h"
  31 #include "qemu/fifo8.h"
  32 #include "qom/object.h"
  33
  34 #define UART_FIFO_LENGTH    16      /* 16550A Fifo Length */
  35
  36 struct SerialState {
  37     DeviceState parent;
  38
  39     uint16_t divider;
  40     uint8_t rbr; /* receive register */
  41     uint8_t thr; /* transmit holding register */
  42     uint8_t tsr; /* transmit shift register */
  43     uint8_t ier;
  44     uint8_t iir; /* read only */
  45     uint8_t lcr;
  46     uint8_t mcr;
  47     uint8_t lsr; /* read only */
  48     uint8_t msr; /* read only */
  49     uint8_t scr;
  50     uint8_t fcr;
  51     uint8_t fcr_vmstate; /* we can't write directly this value
  52                             it has side effects */
  53     /* NOTE: this hidden state is necessary for tx irq generation as
  54        it can be reset while reading iir */
  55     int thr_ipending;
  56     qemu_irq irq;
  57     CharBackend chr;
  58     int last_break_enable;
  59     uint32_t baudbase;
  60     uint32_t tsr_retry;
  61     guint watch_tag;
  62     bool wakeup;
  63
  64     /* Time when the last byte was successfully sent out of the tsr */
  65     uint64_t last_xmit_ts;
  66     Fifo8 recv_fifo;
  67     Fifo8 xmit_fifo;
  68     /* Interrupt trigger level for recv_fifo */
  69     uint8_t recv_fifo_itl;
  70
  71     QEMUTimer *fifo_timeout_timer;
  72     int timeout_ipending;           /* timeout interrupt pending state */
  73
  74     uint64_t char_transmit_time;    /* time to transmit a char in ticks */
  75     int poll_msl;
  76
  77     QEMUTimer *modem_status_poll;
  78     MemoryRegion io;
  79 };
  80 typedef struct SerialState SerialState;
  81
  82 extern const VMStateDescription vmstate_serial;
  83 extern const MemoryRegionOps serial_io_ops;
  84
  85 #define TYPE_SERIAL "serial"
  86 OBJECT_DECLARE_SIMPLE_TYPE(SerialState, SERIAL)
  87
  88 #endif