1 /*
2 * Interface for the 93C66/56/46/26/06 serial eeprom parts.
3 *
4 * Copyright (c) 1995, 1996 Daniel M. Eischen
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions, and the following disclaimer,
12 * without modification.
13 * 2. The name of the author may not be used to endorse or promote products
14 * derived from this software without specific prior written permission.
15 *
16 * Alternatively, this software may be distributed under the terms of the
17 * GNU General Public License ("GPL").
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
23 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * $Id: //depot/aic7xxx/aic7xxx/aic7xxx_93cx6.c#17 $
32 *
33 * $FreeBSD$
34 */
35
36 /*
37 * The instruction set of the 93C66/56/46/26/06 chips are as follows:
38 *
39 * Start OP *
40 * Function Bit Code Address** Data Description
41 * -------------------------------------------------------------------
42 * READ 1 10 A5 - A0 Reads data stored in memory,
43 * starting at specified address
44 * EWEN 1 00 11XXXX Write enable must precede
45 * all programming modes
46 * ERASE 1 11 A5 - A0 Erase register A5A4A3A2A1A0
47 * WRITE 1 01 A5 - A0 D15 - D0 Writes register
48 * ERAL 1 00 10XXXX Erase all registers
49 * WRAL 1 00 01XXXX D15 - D0 Writes to all registers
50 * EWDS 1 00 00XXXX Disables all programming
51 * instructions
52 * *Note: A value of X for address is a don't care condition.
53 * **Note: There are 8 address bits for the 93C56/66 chips unlike
54 * the 93C46/26/06 chips which have 6 address bits.
55 *
56 * The 93C46 has a four wire interface: clock, chip select, data in, and
57 * data out. In order to perform one of the above functions, you need
58 * to enable the chip select for a clock period (typically a minimum of
59 * 1 usec, with the clock high and low a minimum of 750 and 250 nsec
60 * respectively). While the chip select remains high, you can clock in
61 * the instructions (above) starting with the start bit, followed by the
62 * OP code, Address, and Data (if needed). For the READ instruction, the
63 * requested 16-bit register contents is read from the data out line but
64 * is preceded by an initial zero (leading 0, followed by 16-bits, MSB
65 * first). The clock cycling from low to high initiates the next data
66 * bit to be sent from the chip.
67 *
68 */
69
70 #ifdef __linux__
71 #include "aic7xxx_osm.h"
72 #include "aic7xxx_inline.h"
73 #include "aic7xxx_93cx6.h"
74 #else
75 #include <dev/aic7xxx/aic7xxx_osm.h>
76 #include <dev/aic7xxx/aic7xxx_inline.h>
77 #include <dev/aic7xxx/aic7xxx_93cx6.h>
78 #endif
79
80 /*
81 * Right now, we only have to read the SEEPROM. But we make it easier to
82 * add other 93Cx6 functions.
83 */
84 static struct seeprom_cmd {
85 uint8_t len;
86 uint8_t bits[9];
87 } seeprom_read = {3, {1, 1, 0}};
88
89 static struct seeprom_cmd seeprom_ewen = {9, {1, 0, 0, 1, 1, 0, 0, 0, 0}};
90 static struct seeprom_cmd seeprom_ewds = {9, {1, 0, 0, 0, 0, 0, 0, 0, 0}};
91 static struct seeprom_cmd seeprom_write = {3, {1, 0, 1}};
92
93 /*
94 * Wait for the SEERDY to go high; about 800 ns.
95 */
96 #define CLOCK_PULSE(sd, rdy) \
97 while ((SEEPROM_STATUS_INB(sd) & rdy) == 0) { \
98 ; /* Do nothing */ \
99 } \
100 (void)SEEPROM_INB(sd); /* Clear clock */
101
102 /*
103 * Send a START condition and the given command
104 */
105 static void
send_seeprom_cmd(struct seeprom_descriptor * sd,struct seeprom_cmd * cmd)106 send_seeprom_cmd(struct seeprom_descriptor *sd, struct seeprom_cmd *cmd)
107 {
108 uint8_t temp;
109 int i = 0;
110
111 /* Send chip select for one clock cycle. */
112 temp = sd->sd_MS ^ sd->sd_CS;
113 SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
114 CLOCK_PULSE(sd, sd->sd_RDY);
115
116 for (i = 0; i < cmd->len; i++) {
117 if (cmd->bits[i] != 0)
118 temp ^= sd->sd_DO;
119 SEEPROM_OUTB(sd, temp);
120 CLOCK_PULSE(sd, sd->sd_RDY);
121 SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
122 CLOCK_PULSE(sd, sd->sd_RDY);
123 if (cmd->bits[i] != 0)
124 temp ^= sd->sd_DO;
125 }
126 }
127
128 /*
129 * Clear CS put the chip in the reset state, where it can wait for new commands.
130 */
131 static void
reset_seeprom(struct seeprom_descriptor * sd)132 reset_seeprom(struct seeprom_descriptor *sd)
133 {
134 uint8_t temp;
135
136 temp = sd->sd_MS;
137 SEEPROM_OUTB(sd, temp);
138 CLOCK_PULSE(sd, sd->sd_RDY);
139 SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
140 CLOCK_PULSE(sd, sd->sd_RDY);
141 SEEPROM_OUTB(sd, temp);
142 CLOCK_PULSE(sd, sd->sd_RDY);
143 }
144
145 /*
146 * Read the serial EEPROM and returns 1 if successful and 0 if
147 * not successful.
148 */
149 int
ahc_read_seeprom(struct seeprom_descriptor * sd,uint16_t * buf,u_int start_addr,u_int count)150 ahc_read_seeprom(struct seeprom_descriptor *sd, uint16_t *buf,
151 u_int start_addr, u_int count)
152 {
153 int i = 0;
154 u_int k = 0;
155 uint16_t v;
156 uint8_t temp;
157
158 /*
159 * Read the requested registers of the seeprom. The loop
160 * will range from 0 to count-1.
161 */
162 for (k = start_addr; k < count + start_addr; k++) {
163 /*
164 * Now we're ready to send the read command followed by the
165 * address of the 16-bit register we want to read.
166 */
167 send_seeprom_cmd(sd, &seeprom_read);
168
169 /* Send the 6 or 8 bit address (MSB first, LSB last). */
170 temp = sd->sd_MS ^ sd->sd_CS;
171 for (i = (sd->sd_chip - 1); i >= 0; i--) {
172 if ((k & (1 << i)) != 0)
173 temp ^= sd->sd_DO;
174 SEEPROM_OUTB(sd, temp);
175 CLOCK_PULSE(sd, sd->sd_RDY);
176 SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
177 CLOCK_PULSE(sd, sd->sd_RDY);
178 if ((k & (1 << i)) != 0)
179 temp ^= sd->sd_DO;
180 }
181
182 /*
183 * Now read the 16 bit register. An initial 0 precedes the
184 * register contents which begins with bit 15 (MSB) and ends
185 * with bit 0 (LSB). The initial 0 will be shifted off the
186 * top of our word as we let the loop run from 0 to 16.
187 */
188 v = 0;
189 for (i = 16; i >= 0; i--) {
190 SEEPROM_OUTB(sd, temp);
191 CLOCK_PULSE(sd, sd->sd_RDY);
192 v <<= 1;
193 if (SEEPROM_DATA_INB(sd) & sd->sd_DI)
194 v |= 1;
195 SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
196 CLOCK_PULSE(sd, sd->sd_RDY);
197 }
198
199 buf[k - start_addr] = v;
200
201 /* Reset the chip select for the next command cycle. */
202 reset_seeprom(sd);
203 }
204 #ifdef AHC_DUMP_EEPROM
205 printf("\nSerial EEPROM:\n\t");
206 for (k = 0; k < count; k = k + 1) {
207 if (((k % 8) == 0) && (k != 0)) {
208 printf ("\n\t");
209 }
210 printf (" 0x%x", buf[k]);
211 }
212 printf ("\n");
213 #endif
214 return (1);
215 }
216
217 /*
218 * Write the serial EEPROM and return 1 if successful and 0 if
219 * not successful.
220 */
221 int
ahc_write_seeprom(struct seeprom_descriptor * sd,uint16_t * buf,u_int start_addr,u_int count)222 ahc_write_seeprom(struct seeprom_descriptor *sd, uint16_t *buf,
223 u_int start_addr, u_int count)
224 {
225 uint16_t v;
226 uint8_t temp;
227 int i, k;
228
229 /* Place the chip into write-enable mode */
230 send_seeprom_cmd(sd, &seeprom_ewen);
231 reset_seeprom(sd);
232
233 /* Write all requested data out to the seeprom. */
234 temp = sd->sd_MS ^ sd->sd_CS;
235 for (k = start_addr; k < count + start_addr; k++) {
236 /* Send the write command */
237 send_seeprom_cmd(sd, &seeprom_write);
238
239 /* Send the 6 or 8 bit address (MSB first). */
240 for (i = (sd->sd_chip - 1); i >= 0; i--) {
241 if ((k & (1 << i)) != 0)
242 temp ^= sd->sd_DO;
243 SEEPROM_OUTB(sd, temp);
244 CLOCK_PULSE(sd, sd->sd_RDY);
245 SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
246 CLOCK_PULSE(sd, sd->sd_RDY);
247 if ((k & (1 << i)) != 0)
248 temp ^= sd->sd_DO;
249 }
250
251 /* Write the 16 bit value, MSB first */
252 v = buf[k - start_addr];
253 for (i = 15; i >= 0; i--) {
254 if ((v & (1 << i)) != 0)
255 temp ^= sd->sd_DO;
256 SEEPROM_OUTB(sd, temp);
257 CLOCK_PULSE(sd, sd->sd_RDY);
258 SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
259 CLOCK_PULSE(sd, sd->sd_RDY);
260 if ((v & (1 << i)) != 0)
261 temp ^= sd->sd_DO;
262 }
263
264 /* Wait for the chip to complete the write */
265 temp = sd->sd_MS;
266 SEEPROM_OUTB(sd, temp);
267 CLOCK_PULSE(sd, sd->sd_RDY);
268 temp = sd->sd_MS ^ sd->sd_CS;
269 do {
270 SEEPROM_OUTB(sd, temp);
271 CLOCK_PULSE(sd, sd->sd_RDY);
272 SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
273 CLOCK_PULSE(sd, sd->sd_RDY);
274 } while ((SEEPROM_DATA_INB(sd) & sd->sd_DI) == 0);
275
276 reset_seeprom(sd);
277 }
278
279 /* Put the chip back into write-protect mode */
280 send_seeprom_cmd(sd, &seeprom_ewds);
281 reset_seeprom(sd);
282
283 return (1);
284 }
285
286 int
ahc_verify_cksum(struct seeprom_config * sc)287 ahc_verify_cksum(struct seeprom_config *sc)
288 {
289 int i;
290 int maxaddr;
291 uint32_t checksum;
292 uint16_t *scarray;
293
294 maxaddr = (sizeof(*sc)/2) - 1;
295 checksum = 0;
296 scarray = (uint16_t *)sc;
297
298 for (i = 0; i < maxaddr; i++)
299 checksum = checksum + scarray[i];
300 if (checksum == 0
301 || (checksum & 0xFFFF) != sc->checksum) {
302 return (0);
303 } else {
304 return(1);
305 }
306 }
307