Commit | Line | Data |
---|---|---|
9893f627 DR |
1 | # |
2 | /* | |
3 | */ | |
4 | ||
5 | /* | |
6 | * DP-11 Synchronous interface driver | |
7 | * This driver is rather insensitive to the remote | |
8 | * device it talks to, which is to say most of the protocol | |
9 | * must be supplied by the calling program. | |
10 | * Exceptions: parity is even; 7 data bits per character; | |
11 | * max. of 512 characters per record; 10 second timeout | |
12 | * on waiting to receive; half-duplex transmission. | |
13 | */ | |
14 | ||
15 | #include "../param.h" | |
16 | #include "../conf.h" | |
17 | #include "../user.h" | |
18 | #include "../buf.h" | |
19 | ||
20 | /* control info */ | |
21 | struct { | |
22 | char *dp_buf; | |
23 | char *dp_bufp; | |
24 | int dp_nxmit; | |
25 | char dp_state; | |
26 | char dp_timer; | |
27 | int dp_proc; | |
28 | } dp11; | |
29 | ||
30 | /* device registers */ | |
31 | struct { | |
32 | int dprcsr; | |
33 | char dprbuf; | |
34 | char dpsyn0; | |
35 | int dptcsr; | |
36 | char dptbuf; | |
37 | char dpsyn1; | |
38 | }; | |
39 | ||
40 | /* bits */ | |
41 | #define ODDPAR 010000 | |
42 | #define IENABLE 0100 | |
43 | #define HDUPLX 02 | |
44 | ||
45 | #define CTRANS 0100000 | |
46 | #define RORUN 040000 | |
47 | #define RING 020000 | |
48 | #define DSRDY 010000 | |
49 | #define CARRIER 04000 | |
50 | #define DONE 0200 | |
51 | #define IENABLE 0100 | |
52 | #define SIENABL 040 | |
53 | ||
54 | #define WRITE 1 | |
55 | #define READ 0 | |
56 | ||
57 | #define DTRDY 01 | |
58 | #define RCVACT 04000 | |
59 | ||
60 | #define DPADDR 0174770 | |
61 | #define DPPRI 5 | |
62 | #define SYN 026 /* (receive) sync character */ | |
63 | ||
64 | /* | |
65 | * The open fails unless the device is not open or | |
66 | * the opening process is the one that has it open already. | |
67 | */ | |
68 | dpopen(dev, flag) | |
69 | { | |
70 | int dptimeout(); | |
71 | ||
72 | if (dp11.dp_proc!=0 && dp11.dp_proc!=u.u_procp) { | |
73 | u.u_error = ENXIO; | |
74 | return; | |
75 | } | |
76 | dp11.dp_proc = u.u_procp; | |
77 | dp11.dp_state = READ; | |
78 | if (dp11.dp_buf==0) { | |
79 | dp11.dp_buf = getblk(NODEV); | |
80 | dp11.dp_bufp = dp11.dp_buf->b_addr; | |
81 | dp11.dp_timer = HZ; | |
82 | timeout(dptimeout, 0, HZ); | |
83 | } | |
84 | DPADDR->dpsyn0 = SYN; | |
85 | DPADDR->dprcsr = HDUPLX|IENABLE; | |
86 | DPADDR->dptcsr = IENABLE|SIENABL|DTRDY; | |
87 | } | |
88 | ||
89 | dpclose() | |
90 | { | |
91 | DPADDR->dprcsr = 0; | |
92 | DPADDR->dptcsr = 0; | |
93 | dp11.dp_timer = 0; | |
94 | dp11.dp_proc = 0; | |
95 | if (dp11.dp_buf != 0) { | |
96 | brelse(dp11.dp_buf); | |
97 | dp11.dp_buf = 0; | |
98 | } | |
99 | } | |
100 | ||
101 | /* | |
102 | * Read waits until: | |
103 | * there is loss of "data set ready", or | |
104 | * a timeout occurs, or | |
105 | * a full record has been received. | |
106 | * The former two result in an error. | |
107 | */ | |
108 | dpread() | |
109 | { | |
110 | register char *bp, **epp; | |
111 | ||
112 | bp = dp11.dp_buf->b_addr; | |
113 | epp = &dp11.dp_bufp; | |
114 | for(;;) { | |
115 | if(dpwait()) | |
116 | return; | |
117 | if (*epp > bp) | |
118 | break; | |
119 | spl6(); | |
120 | if (dp11.dp_timer <= 1) { | |
121 | spl0(); | |
122 | return; | |
123 | } | |
124 | sleep(&dp11, DPPRI); | |
125 | spl0(); | |
126 | } | |
127 | iomove(dp11.dp_buf, 0, min(u.u_count, *epp-bp), B_READ); | |
128 | } | |
129 | ||
130 | /* | |
131 | * write checks to make sure that the data set is not reading, | |
132 | * and that it is ready. Then the record is copied | |
133 | * and transmission started. | |
134 | */ | |
135 | dpwrite() | |
136 | { | |
137 | register char *bp; | |
138 | ||
139 | if (u.u_count==0 || dpwait()) | |
140 | return; | |
141 | dp11.dp_state = WRITE; | |
142 | bp = dp11.dp_buf->b_addr; | |
143 | dp11.dp_bufp = bp; | |
144 | if (u.u_count>512) | |
145 | u.u_count = 512; | |
146 | dp11.dp_nxmit = u.u_count; | |
147 | iomove(dp11.dp_buf, 0, u.u_count, B_WRITE); | |
148 | dpstart(); | |
149 | } | |
150 | ||
151 | /* | |
152 | * If "data set ready" is down return an error; otherwise | |
153 | * wait until the dataset is in read state with no carrier, | |
154 | * which means a record has just been received. | |
155 | */ | |
156 | dpwait() | |
157 | { | |
158 | for(;;) { | |
159 | if ((DPADDR->dptcsr&DSRDY)==0 || dp11.dp_buf==0) { | |
160 | u.u_error = EIO; | |
161 | return(1); | |
162 | } | |
163 | spl6(); | |
164 | if (dp11.dp_state==READ && (DPADDR->dptcsr&CARRIER)==0) { | |
165 | spl0(); | |
166 | return(0); | |
167 | } | |
168 | sleep(&dp11, DPPRI); | |
169 | spl0(); | |
170 | } | |
171 | } | |
172 | ||
173 | /* | |
174 | * Start off the next character to be transmitted; | |
175 | * when the record is done, drop back into read state. | |
176 | */ | |
177 | dpstart() | |
178 | { | |
179 | register int c; | |
180 | extern char partab[]; | |
181 | ||
182 | dp11.dp_timer = 10; | |
183 | if (--dp11.dp_nxmit >= 0) { | |
184 | c = (*dp11.dp_bufp++) & 0177; | |
185 | DPADDR->dptbuf = c | ~partab[c]&0200; | |
186 | } else { | |
187 | dp11.dp_bufp = dp11.dp_buf->b_addr; | |
188 | dp11.dp_state = READ; | |
189 | } | |
190 | } | |
191 | ||
192 | /* | |
193 | * Count down the DP timer (once per second) | |
194 | * If it runs out, it presumably means the other station | |
195 | * won't speak. | |
196 | */ | |
197 | dptimeout() | |
198 | { | |
199 | if (dp11.dp_timer==0) | |
200 | return; | |
201 | if (--dp11.dp_timer==0) { | |
202 | dpturnaround(); | |
203 | dp11.dp_timer = 1; | |
204 | } | |
205 | timeout(dptimeout, 0, HZ); | |
206 | } | |
207 | ||
208 | /* | |
209 | * Receiver interrupt: if reading, stash character | |
210 | * unless there is an overrun. | |
211 | */ | |
212 | dprint() | |
213 | { | |
214 | register int c; | |
215 | ||
216 | c = DPADDR->dprbuf & 0177; | |
217 | if (dp11.dp_state==READ) { | |
218 | if ((DPADDR->dprcsr&ODDPAR) == 0) | |
219 | c =| 0200; | |
220 | if (dp11.dp_bufp < dp11.dp_buf->b_addr+512) | |
221 | *dp11.dp_bufp++ = c; | |
222 | } | |
223 | } | |
224 | ||
225 | /* | |
226 | * Transmitter interrupt: | |
227 | * Knock down hardware bits. | |
228 | * If carrier has dropped, the record is done, so turn the line around; | |
229 | * otherwise start another character. | |
230 | */ | |
231 | dpxint() | |
232 | { | |
233 | register int dpstat; | |
234 | ||
235 | dpstat = DPADDR->dptcsr; | |
236 | DPADDR->dptcsr =& ~(CTRANS|RORUN|RING|DONE); | |
237 | if (dpstat & (CTRANS|RORUN)) | |
238 | dpturnaround(); | |
239 | else if (dpstat&DONE && dp11.dp_state==WRITE) | |
240 | dpstart(); | |
241 | } | |
242 | ||
243 | /* | |
244 | * Change the state from writing to reading at the end of a record. | |
245 | */ | |
246 | dpturnaround() | |
247 | { | |
248 | DPADDR->dprcsr =& ~RCVACT; | |
249 | if (dp11.dp_state==WRITE) { | |
250 | dp11.dp_timer = 10; | |
251 | dp11.dp_state = READ; | |
252 | dp11.dp_bufp = dp11.dp_buf->b_addr; | |
253 | } | |
254 | wakeup(&dp11); | |
255 | } |