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 #ifndef HW_SERIAL_H
  26 #define HW_SERIAL_H 1
  27
  28 #include "hw/hw.h"
  29 #include "sysemu/sysemu.h"
  30 #include "exec/memory.h"
  31 #include "qemu/fifo8.h"
  32
  33 #define UART_FIFO_LENGTH    16      /* 16550A Fifo Length */
  34
  35 struct SerialState {
  36     uint16_t divider;
  37     uint8_t rbr; /* receive register */
  38     uint8_t thr; /* transmit holding register */
  39     uint8_t tsr; /* transmit shift register */
  40     uint8_t ier;
  41     uint8_t iir; /* read only */
  42     uint8_t lcr;
  43     uint8_t mcr;
  44     uint8_t lsr; /* read only */
  45     uint8_t msr; /* read only */
  46     uint8_t scr;
  47     uint8_t fcr;
  48     uint8_t fcr_vmstate; /* we can't write directly this value
  49                             it has side effects */
  50     /* NOTE: this hidden state is necessary for tx irq generation as
  51        it can be reset while reading iir */
  52     int thr_ipending;
  53     qemu_irq irq;
  54     CharDriverState *chr;
  55     int last_break_enable;
  56     int it_shift;
  57     int baudbase;
  58     int tsr_retry;
  59     uint32_t wakeup;
  60
  61     /* Time when the last byte was successfully sent out of the tsr */
  62     uint64_t last_xmit_ts;
  63     Fifo8 recv_fifo;
  64     Fifo8 xmit_fifo;
  65     /* Interrupt trigger level for recv_fifo */
  66     uint8_t recv_fifo_itl;
  67
  68     struct QEMUTimer *fifo_timeout_timer;
  69     int timeout_ipending;           /* timeout interrupt pending state */
  70
  71     uint64_t char_transmit_time;    /* time to transmit a char in ticks */
  72     int poll_msl;
  73
  74     struct QEMUTimer *modem_status_poll;
  75     MemoryRegion io;
  76 };
  77
  78 extern const VMStateDescription vmstate_serial;
  79 extern const MemoryRegionOps serial_io_ops;
  80
  81 void serial_init_core(SerialState *s);
  82 void serial_exit_core(SerialState *s);
  83 void serial_set_frequency(SerialState *s, uint32_t frequency);
  84
  85 /* legacy pre qom */
  86 SerialState *serial_init(int base, qemu_irq irq, int baudbase,
  87                          CharDriverState *chr, MemoryRegion *system_io);
  88 SerialState *serial_mm_init(MemoryRegion *address_space,
  89                             hwaddr base, int it_shift,
  90                             qemu_irq irq, int baudbase,
  91                             CharDriverState *chr, enum device_endian end);
  92
  93 /* serial-isa.c */
  94 #define TYPE_ISA_SERIAL "isa-serial"
  95 bool serial_isa_init(ISABus *bus, int index, CharDriverState *chr);
  96
  97 #endif