xref: /netbsd-src/external/gpl3/gdb/dist/sim/m32r/dv-m32r_uart.c (revision 05fa08567a80471fd0eb3843a238392874f2577c)
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 };
143