xref: /netbsd-src/external/gpl3/gdb/dist/sim/m32r/dv-m32r_uart.c (revision ccd9df534e375a4366c5b55f23782053c7a98d82)
1 /* UART model.
2 
3    Copyright (C) 1996-2023 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   struct m32r_uart *uart = hw_data (me);
40   int status = dv_sockser_status (sd);
41 
42   switch (addr)
43     {
44     case UART_OUTCHAR_ADDR:
45       if (status & DV_SOCKSER_DISCONNECTED)
46 	{
47 	  sim_io_write_stdout (sd, source, nr_bytes);
48 	  sim_io_flush_stdout (sd);
49 	}
50       else
51 	{
52 	  /* Normalize errors to a value of 0.  */
53 	  int ret = dv_sockser_write_buffer (sd, source, nr_bytes);
54 	  if (ret < 0)
55 	    nr_bytes = 0;
56 	}
57       break;
58     }
59 
60   return nr_bytes;
61 }
62 
63 static unsigned
64 m32r_uart_io_read_buffer (struct hw *me, void *dest,
65 			  int space, address_word addr, unsigned nr_bytes)
66 {
67   SIM_DESC sd = hw_system (me);
68   struct m32r_uart *uart = hw_data (me);
69   int status = dv_sockser_status (sd);
70 
71   switch (addr)
72     {
73     case UART_INCHAR_ADDR:
74       if (status & DV_SOCKSER_DISCONNECTED)
75 	{
76 	  int ret = sim_io_poll_read (sd, 0/*STDIN*/, dest, 1);
77 	  return (ret < 0) ? 0 : 1;
78         }
79       else
80 	{
81 	  char *buffer = dest;
82 	  buffer[0] = dv_sockser_read (sd);
83 	  return 1;
84 	}
85     case UART_STATUS_ADDR:
86       {
87 	unsigned char *p = dest;
88 	p[0] = 0;
89 	p[1] = (((status & DV_SOCKSER_INPUT_EMPTY)
90 #ifdef UART_INPUT_READY0
91 		 ? UART_INPUT_READY : 0)
92 #else
93 		 ? 0 : UART_INPUT_READY)
94 #endif
95 		+ ((status & DV_SOCKSER_OUTPUT_EMPTY) ? UART_OUTPUT_READY : 0));
96 	return 2;
97       }
98     }
99 
100   return nr_bytes;
101 }
102 
103 static void
104 attach_m32r_uart_regs (struct hw *me, struct m32r_uart *uart)
105 {
106   address_word attach_address;
107   int attach_space;
108   unsigned attach_size;
109   reg_property_spec reg;
110 
111   if (hw_find_property (me, "reg") == NULL)
112     hw_abort (me, "Missing \"reg\" property");
113 
114   if (!hw_find_reg_array_property (me, "reg", 0, &reg))
115     hw_abort (me, "\"reg\" property must contain three addr/size entries");
116 
117   hw_unit_address_to_attach_address (hw_parent (me),
118 				     &reg.address,
119 				     &attach_space, &attach_address, me);
120   hw_unit_size_to_attach_size (hw_parent (me), &reg.size, &attach_size, me);
121 
122   hw_attach_address (hw_parent (me),
123 		     0, attach_space, attach_address, attach_size, me);
124 }
125 
126 static void
127 m32r_uart_finish (struct hw *me)
128 {
129   struct m32r_uart *uart;
130 
131   uart = HW_ZALLOC (me, struct m32r_uart);
132 
133   set_hw_data (me, uart);
134   set_hw_io_read_buffer (me, m32r_uart_io_read_buffer);
135   set_hw_io_write_buffer (me, m32r_uart_io_write_buffer);
136 
137   attach_m32r_uart_regs (me, uart);
138 }
139 
140 const struct hw_descriptor dv_m32r_uart_descriptor[] =
141 {
142   {"m32r_uart", m32r_uart_finish,},
143   {NULL, NULL},
144 };
145