root / hw / parallel.c @ f68c781c
History | View | Annotate | Download (5.2 kB)
1 |
/*
|
---|---|
2 |
* QEMU Parallel PORT emulation
|
3 |
*
|
4 |
* Copyright (c) 2003-2004 Fabrice Bellard
|
5 |
*
|
6 |
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
7 |
* of this software and associated documentation files (the "Software"), to deal
|
8 |
* in the Software without restriction, including without limitation the rights
|
9 |
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
10 |
* copies of the Software, and to permit persons to whom the Software is
|
11 |
* furnished to do so, subject to the following conditions:
|
12 |
*
|
13 |
* The above copyright notice and this permission notice shall be included in
|
14 |
* all copies or substantial portions of the Software.
|
15 |
*
|
16 |
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
17 |
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
18 |
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
19 |
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
20 |
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
21 |
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
22 |
* THE SOFTWARE.
|
23 |
*/
|
24 |
#include "vl.h" |
25 |
|
26 |
//#define DEBUG_PARALLEL
|
27 |
|
28 |
/*
|
29 |
* These are the definitions for the Printer Status Register
|
30 |
*/
|
31 |
#define PARA_STS_BUSY 0x80 /* Busy complement */ |
32 |
#define PARA_STS_ACK 0x40 /* Acknowledge */ |
33 |
#define PARA_STS_PAPER 0x20 /* Out of paper */ |
34 |
#define PARA_STS_ONLINE 0x10 /* Online */ |
35 |
#define PARA_STS_ERROR 0x08 /* Error complement */ |
36 |
|
37 |
/*
|
38 |
* These are the definitions for the Printer Control Register
|
39 |
*/
|
40 |
#define PARA_CTR_INTEN 0x10 /* IRQ Enable */ |
41 |
#define PARA_CTR_SELECT 0x08 /* Select In complement */ |
42 |
#define PARA_CTR_INIT 0x04 /* Initialize Printer complement */ |
43 |
#define PARA_CTR_AUTOLF 0x02 /* Auto linefeed complement */ |
44 |
#define PARA_CTR_STROBE 0x01 /* Strobe complement */ |
45 |
|
46 |
struct ParallelState {
|
47 |
uint8_t data; |
48 |
uint8_t status; /* read only register */
|
49 |
uint8_t control; |
50 |
int irq;
|
51 |
int irq_pending;
|
52 |
CharDriverState *chr; |
53 |
}; |
54 |
|
55 |
static void parallel_update_irq(ParallelState *s) |
56 |
{ |
57 |
if (s->irq_pending)
|
58 |
pic_set_irq(s->irq, 1);
|
59 |
else
|
60 |
pic_set_irq(s->irq, 0);
|
61 |
} |
62 |
|
63 |
static void parallel_ioport_write(void *opaque, uint32_t addr, uint32_t val) |
64 |
{ |
65 |
ParallelState *s = opaque; |
66 |
|
67 |
addr &= 7;
|
68 |
#ifdef DEBUG_PARALLEL
|
69 |
printf("parallel: write addr=0x%02x val=0x%02x\n", addr, val);
|
70 |
#endif
|
71 |
switch(addr) {
|
72 |
case 0: |
73 |
s->data = val; |
74 |
parallel_update_irq(s); |
75 |
break;
|
76 |
case 2: |
77 |
if ((val & PARA_CTR_INIT) == 0 ) { |
78 |
s->status = PARA_STS_BUSY; |
79 |
s->status |= PARA_STS_ACK; |
80 |
s->status |= PARA_STS_ONLINE; |
81 |
s->status |= PARA_STS_ERROR; |
82 |
} |
83 |
else if (val & PARA_CTR_SELECT) { |
84 |
if (val & PARA_CTR_STROBE) {
|
85 |
s->status &= ~PARA_STS_BUSY; |
86 |
if ((s->control & PARA_CTR_STROBE) == 0) |
87 |
qemu_chr_write(s->chr, &s->data, 1);
|
88 |
} else {
|
89 |
if (s->control & PARA_CTR_INTEN) {
|
90 |
s->irq_pending = 1;
|
91 |
} |
92 |
} |
93 |
} |
94 |
parallel_update_irq(s); |
95 |
s->control = val; |
96 |
break;
|
97 |
} |
98 |
} |
99 |
|
100 |
static uint32_t parallel_ioport_read(void *opaque, uint32_t addr) |
101 |
{ |
102 |
ParallelState *s = opaque; |
103 |
uint32_t ret = 0xff;
|
104 |
|
105 |
addr &= 7;
|
106 |
switch(addr) {
|
107 |
case 0: |
108 |
ret = s->data; |
109 |
break;
|
110 |
case 1: |
111 |
ret = s->status; |
112 |
s->irq_pending = 0;
|
113 |
if ((s->status & PARA_STS_BUSY) == 0 && (s->control & PARA_CTR_STROBE) == 0) { |
114 |
/* XXX Fixme: wait 5 microseconds */
|
115 |
if (s->status & PARA_STS_ACK)
|
116 |
s->status &= ~PARA_STS_ACK; |
117 |
else {
|
118 |
/* XXX Fixme: wait 5 microseconds */
|
119 |
s->status |= PARA_STS_ACK; |
120 |
s->status |= PARA_STS_BUSY; |
121 |
} |
122 |
} |
123 |
parallel_update_irq(s); |
124 |
break;
|
125 |
case 2: |
126 |
ret = s->control; |
127 |
break;
|
128 |
} |
129 |
#ifdef DEBUG_PARALLEL
|
130 |
printf("parallel: read addr=0x%02x val=0x%02x\n", addr, ret);
|
131 |
#endif
|
132 |
return ret;
|
133 |
} |
134 |
|
135 |
static int parallel_can_receive(ParallelState *s) |
136 |
{ |
137 |
return 0; |
138 |
} |
139 |
|
140 |
static void parallel_receive_byte(ParallelState *s, int ch) |
141 |
{ |
142 |
} |
143 |
|
144 |
static int parallel_can_receive1(void *opaque) |
145 |
{ |
146 |
ParallelState *s = opaque; |
147 |
return parallel_can_receive(s);
|
148 |
} |
149 |
|
150 |
static void parallel_receive1(void *opaque, const uint8_t *buf, int size) |
151 |
{ |
152 |
ParallelState *s = opaque; |
153 |
parallel_receive_byte(s, buf[0]);
|
154 |
} |
155 |
|
156 |
static void parallel_event(void *opaque, int event) |
157 |
{ |
158 |
} |
159 |
|
160 |
/* If fd is zero, it means that the parallel device uses the console */
|
161 |
ParallelState *parallel_init(int base, int irq, CharDriverState *chr) |
162 |
{ |
163 |
ParallelState *s; |
164 |
|
165 |
s = qemu_mallocz(sizeof(ParallelState));
|
166 |
if (!s)
|
167 |
return NULL; |
168 |
s->irq = irq; |
169 |
s->data = 0;
|
170 |
s->status = PARA_STS_BUSY; |
171 |
s->status |= PARA_STS_ACK; |
172 |
s->status |= PARA_STS_ONLINE; |
173 |
s->status |= PARA_STS_ERROR; |
174 |
s->control = PARA_CTR_SELECT; |
175 |
s->control |= PARA_CTR_INIT; |
176 |
|
177 |
register_ioport_write(base, 8, 1, parallel_ioport_write, s); |
178 |
register_ioport_read(base, 8, 1, parallel_ioport_read, s); |
179 |
s->chr = chr; |
180 |
qemu_chr_add_read_handler(chr, parallel_can_receive1, parallel_receive1, s); |
181 |
qemu_chr_add_event_handler(chr, parallel_event); |
182 |
return s;
|
183 |
} |