xref: /illumos-gate/usr/src/boot/common/isapnp.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
1 /*
2  * Copyright (c) 1998, Michael Smith
3  * Copyright (c) 1996, Sujal M. Patel
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 
30 /*
31  * Machine-independant ISA PnP enumerator implementing a subset of the
32  * ISA PnP specification.
33  */
34 #include <stand.h>
35 #include <string.h>
36 #include <bootstrap.h>
37 #include <isapnp.h>
38 
39 #define	inb(x)		(archsw.arch_isainb((x)))
40 #define	outb(x, y)	(archsw.arch_isaoutb((x), (y)))
41 
42 static void	isapnp_write(int d, int r);
43 static void	isapnp_send_Initiation_LFSR(void);
44 static int	isapnp_get_serial(uint8_t *p);
45 static int	isapnp_isolation_protocol(void);
46 static void	isapnp_enumerate(void);
47 
48 /* PnP read data port */
49 int		isapnp_readport = 0;
50 
51 #define	_PNP_ID_LEN	9
52 
53 struct pnphandler isapnphandler =
54 {
55 	"ISA bus",
56 	isapnp_enumerate
57 };
58 
59 static void
60 isapnp_write(int d, int r)
61 {
62 	outb(_PNP_ADDRESS, d);
63 	outb(_PNP_WRITE_DATA, r);
64 }
65 
66 /*
67  * Send Initiation LFSR as described in "Plug and Play ISA Specification",
68  * Intel May 94.
69  */
70 static void
71 isapnp_send_Initiation_LFSR(void)
72 {
73 	int cur, i;
74 
75 	/* Reset the LSFR */
76 	outb(_PNP_ADDRESS, 0);
77 	outb(_PNP_ADDRESS, 0); /* yes, we do need it twice! */
78 
79 	cur = 0x6a;
80 	outb(_PNP_ADDRESS, cur);
81 
82 	for (i = 1; i < 32; i++) {
83 		cur = (cur >> 1) | (((cur ^ (cur >> 1)) << 7) & 0xff);
84 		outb(_PNP_ADDRESS, cur);
85 	}
86 }
87 
88 /*
89  * Get the device's serial number.  Returns 1 if the serial is valid.
90  */
91 static int
92 isapnp_get_serial(uint8_t *data)
93 {
94 	int	i, bit, valid = 0, sum = 0x6a;
95 
96 	bzero(data, _PNP_ID_LEN);
97 	outb(_PNP_ADDRESS, SERIAL_ISOLATION);
98 	for (i = 0; i < 72; i++) {
99 		bit = inb(isapnp_readport) == 0x55;
100 		delay(250);	/* Delay 250 usec */
101 
102 		/* Can't Short Circuit the next evaluation, so 'and' is last */
103 		bit = (inb(isapnp_readport) == 0xaa) && bit;
104 		delay(250);	/* Delay 250 usec */
105 
106 		valid = valid || bit;
107 
108 		if (i < 64) {
109 			sum = (sum >> 1) |
110 			    (((sum ^ (sum >> 1) ^ bit) << 7) & 0xff);
111 		}
112 
113 		data[i / 8] = (data[i / 8] >> 1) | (bit ? 0x80 : 0);
114 	}
115 
116 	valid = valid && (data[8] == sum);
117 
118 	return (valid);
119 }
120 
121 /*
122  * Fills the buffer with resource info from the device.
123  * Returns nonzero if the device fails to report
124  */
125 static int
126 isapnp_get_resource_info(uint8_t *buffer, int len)
127 {
128 	int		i, j;
129 	uchar_t	temp;
130 
131 	for (i = 0; i < len; i++) {
132 		outb(_PNP_ADDRESS, STATUS);
133 		for (j = 0; j < 100; j++) {
134 			if ((inb(isapnp_readport)) & 0x1)
135 				break;
136 			delay(1);
137 		}
138 		if (j == 100) {
139 			printf("PnP device failed to report resource data\n");
140 			return (1);
141 		}
142 		outb(_PNP_ADDRESS, RESOURCE_DATA);
143 		temp = inb(isapnp_readport);
144 		if (buffer != NULL)
145 			buffer[i] = temp;
146 	}
147 	return (0);
148 }
149 
150 /*
151  * Scan Resource Data for useful information.
152  *
153  * We scan the resource data for compatible device IDs and
154  * identifier strings; we only take the first identifier string
155  * and assume it's for the card as a whole.
156  *
157  * Returns 0 if the scan completed OK, nonzero on error.
158  */
159 static int
160 isapnp_scan_resdata(struct pnpinfo *pi)
161 {
162 	uchar_t	tag, resinfo[8];
163 	uint_t	limit;
164 	size_t	large_len;
165 	uchar_t	*str;
166 
167 	limit = 1000;
168 	while ((limit-- > 0) && !isapnp_get_resource_info(&tag, 1)) {
169 		if (PNP_RES_TYPE(tag) == 0) {
170 			/* Small resource */
171 			switch (PNP_SRES_NUM(tag)) {
172 			case COMP_DEVICE_ID:
173 				/* Got a compatible device id resource */
174 				if (isapnp_get_resource_info(resinfo,
175 				    PNP_SRES_LEN(tag)))
176 					return (1);
177 				pnp_addident(pi, pnp_eisaformat(resinfo));
178 				return (0);
179 
180 			case END_TAG:
181 				return (0);
182 
183 			default:
184 				/* Skip this resource */
185 				if (isapnp_get_resource_info(NULL,
186 				    PNP_SRES_LEN(tag)))
187 					return (1);
188 				break;
189 			}
190 		} else {
191 			/* Large resource */
192 			if (isapnp_get_resource_info(resinfo, 2))
193 				return (1);
194 
195 			large_len = resinfo[1];
196 			large_len = (large_len << 8) + resinfo[0];
197 
198 			switch (PNP_LRES_NUM(tag)) {
199 			case ID_STRING_ANSI:
200 				str = malloc(large_len + 1);
201 				if (isapnp_get_resource_info(str,
202 				    (ssize_t)large_len)) {
203 					free(str);
204 					return (1);
205 				}
206 				str[large_len] = 0;
207 				if (pi->pi_desc == NULL) {
208 					pi->pi_desc = (char *)str;
209 				} else {
210 					free(str);
211 				}
212 				break;
213 
214 			default:
215 				/* Large resource, skip it */
216 				if (isapnp_get_resource_info(NULL,
217 				    (ssize_t)large_len))
218 					return (1);
219 			}
220 		}
221 	}
222 	return (1);
223 }
224 
225 /*
226  * Run the isolation protocol. Upon exiting, all cards are aware that
227  * they should use isapnp_readport as the READ_DATA port.
228  */
229 static int
230 isapnp_isolation_protocol(void)
231 {
232 	int		csn;
233 	struct pnpinfo	*pi;
234 	uint8_t		cardid[_PNP_ID_LEN];
235 	int		ndevs;
236 
237 	isapnp_send_Initiation_LFSR();
238 	ndevs = 0;
239 
240 	isapnp_write(CONFIG_CONTROL, 0x04);	/* Reset CSN for All Cards */
241 
242 	for (csn = 1; ; csn++) {
243 		/* Wake up cards without a CSN (ie. all of them) */
244 		isapnp_write(WAKE, 0);
245 		isapnp_write(SET_RD_DATA, (isapnp_readport >> 2));
246 		outb(_PNP_ADDRESS, SERIAL_ISOLATION);
247 		delay(1000);	/* Delay 1 msec */
248 
249 		if (isapnp_get_serial(cardid)) {
250 			isapnp_write(SET_CSN, csn);
251 			pi = pnp_allocinfo();
252 			ndevs++;
253 			pnp_addident(pi, pnp_eisaformat(cardid));
254 			/*
255 			 * scan the card obtaining all the identifiers it holds
256 			 */
257 			if (isapnp_scan_resdata(pi)) {
258 				/* error getting data, ignore */
259 				pnp_freeinfo(pi);
260 			} else {
261 				pnp_addinfo(pi);
262 			}
263 		} else {
264 			break;
265 		}
266 	}
267 	/* Move all cards to wait-for-key state */
268 	while (--csn > 0) {
269 		isapnp_send_Initiation_LFSR();
270 		isapnp_write(WAKE, csn);
271 		isapnp_write(CONFIG_CONTROL, 0x02);
272 		delay(1000); /* XXX is it really necessary ? */
273 		csn--;
274 	}
275 	return (ndevs);
276 }
277 
278 /*
279  * Locate ISA-PnP devices and populate the supplied list.
280  */
281 static void
282 isapnp_enumerate(void)
283 {
284 	int		pnp_rd_port;
285 
286 	/* Check for I/O port access */
287 	if ((archsw.arch_isainb == NULL) || (archsw.arch_isaoutb == NULL))
288 		return;
289 
290 	/*
291 	 * Validate a possibly-suggested read port value. If the autoscan failed
292 	 * last time, this will return us to autoscan mode again.
293 	 */
294 	if ((isapnp_readport > 0) &&
295 	    (((isapnp_readport < 0x203) ||
296 	    (isapnp_readport > 0x3ff) ||
297 	    (isapnp_readport & 0x3) != 0x3))) {
298 		/* invalid, go look for ourselves */
299 		isapnp_readport = 0;
300 	}
301 
302 	if (isapnp_readport < 0) {
303 		/* someone is telling us there is no ISA in the system */
304 		return;
305 	} else if (isapnp_readport > 0) {
306 		/*
307 		 * Someone has told us where the port is/should be,
308 		 * or we found one last time.
309 		 */
310 		isapnp_isolation_protocol();
311 	} else {
312 		/* No clues, look for it ourselves */
313 		for (pnp_rd_port = 0x80; pnp_rd_port < 0xff;
314 		    pnp_rd_port += 0x10) {
315 			/* Look for something, quit when we find it */
316 			isapnp_readport = (pnp_rd_port << 2) | 0x3;
317 			if (isapnp_isolation_protocol() > 0)
318 				break;
319 		}
320 	}
321 }
322