sim/m32r/dv-m32r_uart.c

   1 /* UART model.
   2
   3    Copyright (C) 1996-2021 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 #include "config.h"
  22
  23 #include "sim-main.h"
  24 #include "hw-main.h"
  25
  26 #include "dv-sockser.h"
  27 #include "dv-m32r_uart.h"
  28
  29 struct m32r_uart
  30 {
  31 };
  32
  33 static unsigned
  34 m32r_uart_io_write_buffer (struct hw *me, const void *source,
  35                            int space, address_word addr, unsigned nr_bytes)
  36 {
  37   SIM_DESC sd = hw_system (me);
  38   struct m32r_uart *uart = hw_data (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   struct m32r_uart *uart = hw_data (me);
  68   int status = dv_sockser_status (sd);
  69
  70   switch (addr)
  71     {
  72     case UART_INCHAR_ADDR:
  73       if (status & DV_SOCKSER_DISCONNECTED)
  74         {
  75           int ret = sim_io_poll_read (sd, 0/*STDIN*/, dest, 1);
  76           return (ret < 0) ? 0 : 1;
  77         }
  78       else
  79         {
  80           char *buffer = dest;
  81           buffer[0] = dv_sockser_read (sd);
  82           return 1;
  83         }
  84     case UART_STATUS_ADDR:
  85       {
  86         unsigned char *p = dest;
  87         p[0] = 0;
  88         p[1] = (((status & DV_SOCKSER_INPUT_EMPTY)
  89 #ifdef UART_INPUT_READY0
  90                  ? UART_INPUT_READY : 0)
  91 #else
  92                  ? 0 : UART_INPUT_READY)
  93 #endif
  94                 + ((status & DV_SOCKSER_OUTPUT_EMPTY) ? UART_OUTPUT_READY : 0));
  95         return 2;
  96       }
  97     }
  98
  99   return nr_bytes;
 100 }
 101
 102 static void
 103 attach_m32r_uart_regs (struct hw *me, struct m32r_uart *uart)
 104 {
 105   address_word attach_address;
 106   int attach_space;
 107   unsigned attach_size;
 108   reg_property_spec reg;
 109
 110   if (hw_find_property (me, "reg") == NULL)
 111     hw_abort (me, "Missing \"reg\" property");
 112
 113   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
 114     hw_abort (me, "\"reg\" property must contain three addr/size entries");
 115
 116   hw_unit_address_to_attach_address (hw_parent (me),
 117                                      &reg.address,
 118                                      &attach_space, &attach_address, me);
 119   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
 120
 121   hw_attach_address (hw_parent (me),
 122                      0, attach_space, attach_address, attach_size, me);
 123 }
 124
 125 static void
 126 m32r_uart_finish (struct hw *me)
 127 {
 128   struct m32r_uart *uart;
 129
 130   uart = HW_ZALLOC (me, struct m32r_uart);
 131
 132   set_hw_data (me, uart);
 133   set_hw_io_read_buffer (me, m32r_uart_io_read_buffer);
 134   set_hw_io_write_buffer (me, m32r_uart_io_write_buffer);
 135
 136   attach_m32r_uart_regs (me, uart);
 137 }
 138
 139 const struct hw_descriptor dv_m32r_uart_descriptor[] =
 140 {
 141   {"m32r_uart", m32r_uart_finish,},
 142   {NULL, NULL},
 143 };