sim/m32r/dv-m32r_uart.c

   1 /* UART model.
   2
   3    Copyright (C) 1996-2024 Free Software Foundation, Inc.
   4    Contributed by Cygnus Solutions and Mike Frysinger.
   5
   6    This file is part of simulators.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 /* This must come before any other includes.  */
  22 #include "defs.h"
  23
  24 #include "sim-main.h"
  25 #include "hw-main.h"
  26
  27 #include "dv-sockser.h"
  28 #include "dv-m32r_uart.h"
  29
  30 struct m32r_uart
  31 {
  32 };
  33
  34 static unsigned
  35 m32r_uart_io_write_buffer (struct hw *me, const void *source,
  36                            int space, address_word addr, unsigned nr_bytes)
  37 {
  38   SIM_DESC sd = hw_system (me);
  39   int status = dv_sockser_status (sd);
  40
  41   switch (addr)
  42     {
  43     case UART_OUTCHAR_ADDR:
  44       if (status & DV_SOCKSER_DISCONNECTED)
  45         {
  46           sim_io_write_stdout (sd, source, nr_bytes);
  47           sim_io_flush_stdout (sd);
  48         }
  49       else
  50         {
  51           /* Normalize errors to a value of 0.  */
  52           int ret = dv_sockser_write_buffer (sd, source, nr_bytes);
  53           if (ret < 0)
  54             nr_bytes = 0;
  55         }
  56       break;
  57     }
  58
  59   return nr_bytes;
  60 }
  61
  62 static unsigned
  63 m32r_uart_io_read_buffer (struct hw *me, void *dest,
  64                           int space, address_word addr, unsigned nr_bytes)
  65 {
  66   SIM_DESC sd = hw_system (me);
  67   int status = dv_sockser_status (sd);
  68
  69   switch (addr)
  70     {
  71     case UART_INCHAR_ADDR:
  72       if (status & DV_SOCKSER_DISCONNECTED)
  73         {
  74           int ret = sim_io_poll_read (sd, 0/*STDIN*/, dest, 1);
  75           return (ret < 0) ? 0 : 1;
  76         }
  77       else
  78         {
  79           char *buffer = dest;
  80           buffer[0] = dv_sockser_read (sd);
  81           return 1;
  82         }
  83     case UART_STATUS_ADDR:
  84       {
  85         unsigned char *p = dest;
  86         p[0] = 0;
  87         p[1] = (((status & DV_SOCKSER_INPUT_EMPTY)
  88 #ifdef UART_INPUT_READY0
  89                  ? UART_INPUT_READY : 0)
  90 #else
  91                  ? 0 : UART_INPUT_READY)
  92 #endif
  93                 + ((status & DV_SOCKSER_OUTPUT_EMPTY) ? UART_OUTPUT_READY : 0));
  94         return 2;
  95       }
  96     }
  97
  98   return nr_bytes;
  99 }
 100
 101 static void
 102 attach_m32r_uart_regs (struct hw *me, struct m32r_uart *uart)
 103 {
 104   address_word attach_address;
 105   int attach_space;
 106   unsigned attach_size;
 107   reg_property_spec reg;
 108
 109   if (hw_find_property (me, "reg") == NULL)
 110     hw_abort (me, "Missing \"reg\" property");
 111
 112   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
 113     hw_abort (me, "\"reg\" property must contain three addr/size entries");
 114
 115   hw_unit_address_to_attach_address (hw_parent (me),
 116                                      &reg.address,
 117                                      &attach_space, &attach_address, me);
 118   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
 119
 120   hw_attach_address (hw_parent (me),
 121                      0, attach_space, attach_address, attach_size, me);
 122 }
 123
 124 static void
 125 m32r_uart_finish (struct hw *me)
 126 {
 127   struct m32r_uart *uart;
 128
 129   uart = HW_ZALLOC (me, struct m32r_uart);
 130
 131   set_hw_data (me, uart);
 132   set_hw_io_read_buffer (me, m32r_uart_io_read_buffer);
 133   set_hw_io_write_buffer (me, m32r_uart_io_write_buffer);
 134
 135   attach_m32r_uart_regs (me, uart);
 136 }
 137
 138 const struct hw_descriptor dv_m32r_uart_descriptor[] =
 139 {
 140   {"m32r_uart", m32r_uart_finish,},
 141   {NULL, NULL},
 142 };