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#19 $ 32 */ 33 34/* 35 * The instruction set of the 93C66/56/46/26/06 chips are as follows: 36 * 37 * Start OP * 38 * Function Bit Code Address** Data Description 39 * ------------------------------------------------------------------- 40 * READ 1 10 A5 - A0 Reads data stored in memory, 41 * starting at specified address 42 * EWEN 1 00 11XXXX Write enable must precede 43 * all programming modes 44 * ERASE 1 11 A5 - A0 Erase register A5A4A3A2A1A0 45 * WRITE 1 01 A5 - A0 D15 - D0 Writes register 46 * ERAL 1 00 10XXXX Erase all registers 47 * WRAL 1 00 01XXXX D15 - D0 Writes to all registers 48 * EWDS 1 00 00XXXX Disables all programming 49 * instructions 50 * *Note: A value of X for address is a don't care condition. 51 * **Note: There are 8 address bits for the 93C56/66 chips unlike 52 * the 93C46/26/06 chips which have 6 address bits. 53 * 54 * The 93C46 has a four wire interface: clock, chip select, data in, and 55 * data out. In order to perform one of the above functions, you need 56 * to enable the chip select for a clock period (typically a minimum of 57 * 1 usec, with the clock high and low a minimum of 750 and 250 nsec 58 * respectively). While the chip select remains high, you can clock in 59 * the instructions (above) starting with the start bit, followed by the 60 * OP code, Address, and Data (if needed). For the READ instruction, the 61 * requested 16-bit register contents is read from the data out line but 62 * is preceded by an initial zero (leading 0, followed by 16-bits, MSB 63 * first). The clock cycling from low to high initiates the next data 64 * bit to be sent from the chip. 65 */ 66 67#ifdef __linux__ 68#include "aic7xxx_osm.h" 69#include "aic7xxx_inline.h" 70#include "aic7xxx_93cx6.h" 71#else 72#include <dev/aic7xxx/aic7xxx_osm.h> 73#include <dev/aic7xxx/aic7xxx_inline.h> 74#include <dev/aic7xxx/aic7xxx_93cx6.h> 75#endif 76 77/* 78 * Right now, we only have to read the SEEPROM. But we make it easier to 79 * add other 93Cx6 functions. 80 */ 81struct seeprom_cmd { 82 uint8_t len; 83 uint8_t bits[11]; 84}; 85 86/* Short opcodes for the c46 */ 87static const struct seeprom_cmd seeprom_ewen = {9, {1, 0, 0, 1, 1, 0, 0, 0, 0}}; 88static const struct seeprom_cmd seeprom_ewds = {9, {1, 0, 0, 0, 0, 0, 0, 0, 0}}; 89 90/* Long opcodes for the C56/C66 */ 91static const struct seeprom_cmd seeprom_long_ewen = {11, {1, 0, 0, 1, 1, 0, 0, 0, 0}}; 92static const struct seeprom_cmd seeprom_long_ewds = {11, {1, 0, 0, 0, 0, 0, 0, 0, 0}}; 93 94/* Common opcodes */ 95static const struct seeprom_cmd seeprom_write = {3, {1, 0, 1}}; 96static const struct seeprom_cmd seeprom_read = {3, {1, 1, 0}}; 97 98/* 99 * Wait for the SEERDY to go high; about 800 ns. 100 */ 101#define CLOCK_PULSE(sd, rdy) \ 102 while ((SEEPROM_STATUS_INB(sd) & rdy) == 0) { \ 103 ; /* Do nothing */ \ 104 } \ 105 (void)SEEPROM_INB(sd); /* Clear clock */ 106 107/* 108 * Send a START condition and the given command 109 */ 110static void 111send_seeprom_cmd(struct seeprom_descriptor *sd, const struct seeprom_cmd *cmd) 112{ 113 uint8_t temp; 114 int i = 0; 115 116 /* Send chip select for one clock cycle. */ 117 temp = sd->sd_MS ^ sd->sd_CS; 118 SEEPROM_OUTB(sd, temp ^ sd->sd_CK); 119 CLOCK_PULSE(sd, sd->sd_RDY); 120 121 for (i = 0; i < cmd->len; i++) { 122 if (cmd->bits[i] != 0) 123 temp ^= sd->sd_DO; 124 SEEPROM_OUTB(sd, temp); 125 CLOCK_PULSE(sd, sd->sd_RDY); 126 SEEPROM_OUTB(sd, temp ^ sd->sd_CK); 127 CLOCK_PULSE(sd, sd->sd_RDY); 128 if (cmd->bits[i] != 0) 129 temp ^= sd->sd_DO; 130 } 131} 132 133/* 134 * Clear CS put the chip in the reset state, where it can wait for new commands. 135 */ 136static void 137reset_seeprom(struct seeprom_descriptor *sd) 138{ 139 uint8_t temp; 140 141 temp = sd->sd_MS; 142 SEEPROM_OUTB(sd, temp); 143 CLOCK_PULSE(sd, sd->sd_RDY); 144 SEEPROM_OUTB(sd, temp ^ sd->sd_CK); 145 CLOCK_PULSE(sd, sd->sd_RDY); 146 SEEPROM_OUTB(sd, temp); 147 CLOCK_PULSE(sd, sd->sd_RDY); 148} 149 150/* 151 * Read the serial EEPROM and returns 1 if successful and 0 if 152 * not successful. 153 */ 154int 155ahc_read_seeprom(struct seeprom_descriptor *sd, uint16_t *buf, 156 u_int start_addr, u_int count) 157{ 158 int i = 0; 159 u_int k = 0; 160 uint16_t v; 161 uint8_t temp; 162 163 /* 164 * Read the requested registers of the seeprom. The loop 165 * will range from 0 to count-1. 166 */ 167 for (k = start_addr; k < count + start_addr; k++) { 168 /* 169 * Now we're ready to send the read command followed by the 170 * address of the 16-bit register we want to read. 171 */ 172 send_seeprom_cmd(sd, &seeprom_read); 173 174 /* Send the 6 or 8 bit address (MSB first, LSB last). */ 175 temp = sd->sd_MS ^ sd->sd_CS; 176 for (i = (sd->sd_chip - 1); i >= 0; i--) { 177 if ((k & (1 << i)) != 0) 178 temp ^= sd->sd_DO; 179 SEEPROM_OUTB(sd, temp); 180 CLOCK_PULSE(sd, sd->sd_RDY); 181 SEEPROM_OUTB(sd, temp ^ sd->sd_CK); 182 CLOCK_PULSE(sd, sd->sd_RDY); 183 if ((k & (1 << i)) != 0) 184 temp ^= sd->sd_DO; 185 } 186 187 /* 188 * Now read the 16 bit register. An initial 0 precedes the 189 * register contents which begins with bit 15 (MSB) and ends 190 * with bit 0 (LSB). The initial 0 will be shifted off the 191 * top of our word as we let the loop run from 0 to 16. 192 */ 193 v = 0; 194 for (i = 16; i >= 0; i--) { 195 SEEPROM_OUTB(sd, temp); 196 CLOCK_PULSE(sd, sd->sd_RDY); 197 v <<= 1; 198 if (SEEPROM_DATA_INB(sd) & sd->sd_DI) 199 v |= 1; 200 SEEPROM_OUTB(sd, temp ^ sd->sd_CK); 201 CLOCK_PULSE(sd, sd->sd_RDY); 202 } 203 204 buf[k - start_addr] = v; 205 206 /* Reset the chip select for the next command cycle. */ 207 reset_seeprom(sd); 208 } 209#ifdef AHC_DUMP_EEPROM 210 printk("\nSerial EEPROM:\n\t"); 211 for (k = 0; k < count; k = k + 1) { 212 if (((k % 8) == 0) && (k != 0)) { 213 printk(KERN_CONT "\n\t"); 214 } 215 printk(KERN_CONT " 0x%x", buf[k]); 216 } 217 printk(KERN_CONT "\n"); 218#endif 219 return (1); 220} 221 222/* 223 * Write the serial EEPROM and return 1 if successful and 0 if 224 * not successful. 225 */ 226int 227ahc_write_seeprom(struct seeprom_descriptor *sd, uint16_t *buf, 228 u_int start_addr, u_int count) 229{ 230 const struct seeprom_cmd *ewen, *ewds; 231 uint16_t v; 232 uint8_t temp; 233 int i, k; 234 235 /* Place the chip into write-enable mode */ 236 if (sd->sd_chip == C46) { 237 ewen = &seeprom_ewen; 238 ewds = &seeprom_ewds; 239 } else if (sd->sd_chip == C56_66) { 240 ewen = &seeprom_long_ewen; 241 ewds = &seeprom_long_ewds; 242 } else { 243 printk("ahc_write_seeprom: unsupported seeprom type %d\n", 244 sd->sd_chip); 245 return (0); 246 } 247 248 send_seeprom_cmd(sd, ewen); 249 reset_seeprom(sd); 250 251 /* Write all requested data out to the seeprom. */ 252 temp = sd->sd_MS ^ sd->sd_CS; 253 for (k = start_addr; k < count + start_addr; k++) { 254 /* Send the write command */ 255 send_seeprom_cmd(sd, &seeprom_write); 256 257 /* Send the 6 or 8 bit address (MSB first). */ 258 for (i = (sd->sd_chip - 1); i >= 0; i--) { 259 if ((k & (1 << i)) != 0) 260 temp ^= sd->sd_DO; 261 SEEPROM_OUTB(sd, temp); 262 CLOCK_PULSE(sd, sd->sd_RDY); 263 SEEPROM_OUTB(sd, temp ^ sd->sd_CK); 264 CLOCK_PULSE(sd, sd->sd_RDY); 265 if ((k & (1 << i)) != 0) 266 temp ^= sd->sd_DO; 267 } 268 269 /* Write the 16 bit value, MSB first */ 270 v = buf[k - start_addr]; 271 for (i = 15; i >= 0; i--) { 272 if ((v & (1 << i)) != 0) 273 temp ^= sd->sd_DO; 274 SEEPROM_OUTB(sd, temp); 275 CLOCK_PULSE(sd, sd->sd_RDY); 276 SEEPROM_OUTB(sd, temp ^ sd->sd_CK); 277 CLOCK_PULSE(sd, sd->sd_RDY); 278 if ((v & (1 << i)) != 0) 279 temp ^= sd->sd_DO; 280 } 281 282 /* Wait for the chip to complete the write */ 283 temp = sd->sd_MS; 284 SEEPROM_OUTB(sd, temp); 285 CLOCK_PULSE(sd, sd->sd_RDY); 286 temp = sd->sd_MS ^ sd->sd_CS; 287 do { 288 SEEPROM_OUTB(sd, temp); 289 CLOCK_PULSE(sd, sd->sd_RDY); 290 SEEPROM_OUTB(sd, temp ^ sd->sd_CK); 291 CLOCK_PULSE(sd, sd->sd_RDY); 292 } while ((SEEPROM_DATA_INB(sd) & sd->sd_DI) == 0); 293 294 reset_seeprom(sd); 295 } 296 297 /* Put the chip back into write-protect mode */ 298 send_seeprom_cmd(sd, ewds); 299 reset_seeprom(sd); 300 301 return (1); 302} 303 304int 305ahc_verify_cksum(struct seeprom_config *sc) 306{ 307 int i; 308 int maxaddr; 309 uint32_t checksum; 310 uint16_t *scarray; 311 312 maxaddr = (sizeof(*sc)/2) - 1; 313 checksum = 0; 314 scarray = (uint16_t *)sc; 315 316 for (i = 0; i < maxaddr; i++) 317 checksum = checksum + scarray[i]; 318 if (checksum == 0 319 || (checksum & 0xFFFF) != sc->checksum) { 320 return (0); 321 } else { 322 return(1); 323 } 324} 325