patch-2.4.3 linux/drivers/scsi/aic7xxx/aic7xxx_93cx6.c

• Lines: 206
• Date: Sun Mar 4 14:30:18 2001
• Orig file: v2.4.2/linux/drivers/scsi/aic7xxx/aic7xxx_93cx6.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.2/linux/drivers/scsi/aic7xxx/aic7xxx_93cx6.c linux/drivers/scsi/aic7xxx/aic7xxx_93cx6.c
@@ -0,0 +1,205 @@
+/*
+ * Interface for the 93C66/56/46/26/06 serial eeprom parts.
+ *
+ * Copyright (c) 1995, 1996 Daniel M. Eischen
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU Public License ("GPL").
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Id: //depot/src/aic7xxx/aic7xxx_93cx6.c#7 $
+ *
+ * $FreeBSD: src/sys/dev/aic7xxx/aic7xxx_93cx6.c,v 1.9 2000/11/10 20:13:41 gibbs Exp $
+ */
+
+/*
+ *   The instruction set of the 93C66/56/46/26/06 chips are as follows:
+ *
+ *               Start  OP	    *
+ *     Function   Bit  Code  Address**  Data     Description
+ *     -------------------------------------------------------------------
+ *     READ        1    10   A5 - A0             Reads data stored in memory,
+ *                                               starting at specified address
+ *     EWEN        1    00   11XXXX              Write enable must preceed
+ *                                               all programming modes
+ *     ERASE       1    11   A5 - A0             Erase register A5A4A3A2A1A0
+ *     WRITE       1    01   A5 - A0   D15 - D0  Writes register
+ *     ERAL        1    00   10XXXX              Erase all registers
+ *     WRAL        1    00   01XXXX    D15 - D0  Writes to all registers
+ *     EWDS        1    00   00XXXX              Disables all programming
+ *                                               instructions
+ *     *Note: A value of X for address is a don't care condition.
+ *    **Note: There are 8 address bits for the 93C56/66 chips unlike
+ *	      the 93C46/26/06 chips which have 6 address bits.
+ *
+ *   The 93C46 has a four wire interface: clock, chip select, data in, and
+ *   data out.  In order to perform one of the above functions, you need
+ *   to enable the chip select for a clock period (typically a minimum of
+ *   1 usec, with the clock high and low a minimum of 750 and 250 nsec
+ *   respectively).  While the chip select remains high, you can clock in
+ *   the instructions (above) starting with the start bit, followed by the
+ *   OP code, Address, and Data (if needed).  For the READ instruction, the
+ *   requested 16-bit register contents is read from the data out line but
+ *   is preceded by an initial zero (leading 0, followed by 16-bits, MSB
+ *   first).  The clock cycling from low to high initiates the next data
+ *   bit to be sent from the chip.
+ *
+ */
+
+#include "aic7xxx_osm.h"
+#include "aic7xxx_inline.h"
+#include "aic7xxx_93cx6.h"
+
+/*
+ * Right now, we only have to read the SEEPROM.  But we make it easier to
+ * add other 93Cx6 functions.
+ */
+static struct seeprom_cmd {
+  	uint8_t len;
+ 	uint8_t bits[3];
+} seeprom_read = {3, {1, 1, 0}};
+
+/*
+ * Wait for the SEERDY to go high; about 800 ns.
+ */
+#define CLOCK_PULSE(sd, rdy)				\
+	while ((SEEPROM_STATUS_INB(sd) & rdy) == 0) {	\
+		;  /* Do nothing */			\
+	}						\
+	(void)SEEPROM_INB(sd);	/* Clear clock */
+
+/*
+ * Read the serial EEPROM and returns 1 if successful and 0 if
+ * not successful.
+ */
+int
+read_seeprom(sd, buf, start_addr, count)
+	struct seeprom_descriptor *sd;
+	uint16_t *buf;
+	u_int start_addr;
+	u_int count;
+{
+	int i = 0;
+	u_int k = 0;
+	uint16_t v;
+	uint8_t temp;
+
+	/*
+	 * Read the requested registers of the seeprom.  The loop
+	 * will range from 0 to count-1.
+	 */
+	for (k = start_addr; k < count + start_addr; k++) {
+		/* Send chip select for one clock cycle. */
+		temp = sd->sd_MS ^ sd->sd_CS;
+		SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
+		CLOCK_PULSE(sd, sd->sd_RDY);
+
+		/*
+		 * Now we're ready to send the read command followed by the
+		 * address of the 16-bit register we want to read.
+		 */
+		for (i = 0; i < seeprom_read.len; i++) {
+			if (seeprom_read.bits[i] != 0)
+				temp ^= sd->sd_DO;
+			SEEPROM_OUTB(sd, temp);
+			CLOCK_PULSE(sd, sd->sd_RDY);
+			SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
+			CLOCK_PULSE(sd, sd->sd_RDY);
+			if (seeprom_read.bits[i] != 0)
+				temp ^= sd->sd_DO;
+		}
+		/* Send the 6 or 8 bit address (MSB first, LSB last). */
+		for (i = (sd->sd_chip - 1); i >= 0; i--) {
+			if ((k & (1 << i)) != 0)
+				temp ^= sd->sd_DO;
+			SEEPROM_OUTB(sd, temp);
+			CLOCK_PULSE(sd, sd->sd_RDY);
+			SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
+			CLOCK_PULSE(sd, sd->sd_RDY);
+			if ((k & (1 << i)) != 0)
+				temp ^= sd->sd_DO;
+		}
+
+		/*
+		 * Now read the 16 bit register.  An initial 0 precedes the
+		 * register contents which begins with bit 15 (MSB) and ends
+		 * with bit 0 (LSB).  The initial 0 will be shifted off the
+		 * top of our word as we let the loop run from 0 to 16.
+		 */
+		v = 0;
+		for (i = 16; i >= 0; i--) {
+			SEEPROM_OUTB(sd, temp);
+			CLOCK_PULSE(sd, sd->sd_RDY);
+			v <<= 1;
+			if (SEEPROM_DATA_INB(sd) & sd->sd_DI)
+				v |= 1;
+			SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
+			CLOCK_PULSE(sd, sd->sd_RDY);
+		}
+
+		buf[k - start_addr] = v;
+
+		/* Reset the chip select for the next command cycle. */
+		temp = sd->sd_MS;
+		SEEPROM_OUTB(sd, temp);
+		CLOCK_PULSE(sd, sd->sd_RDY);
+		SEEPROM_OUTB(sd, temp ^ sd->sd_CK);
+		CLOCK_PULSE(sd, sd->sd_RDY);
+		SEEPROM_OUTB(sd, temp);
+		CLOCK_PULSE(sd, sd->sd_RDY);
+	}
+#ifdef AHC_DUMP_EEPROM
+	printf("\nSerial EEPROM:\n\t");
+	for (k = 0; k < count; k = k + 1) {
+		if (((k % 8) == 0) && (k != 0)) {
+			printf ("\n\t");
+		}
+		printf (" 0x%x", buf[k]);
+	}
+	printf ("\n");
+#endif
+	return (1);
+}
+
+int
+verify_cksum(struct seeprom_config *sc)
+{
+	int i;
+	int maxaddr;
+	uint32_t checksum;
+	uint16_t *scarray;
+
+	maxaddr = (sizeof(*sc)/2) - 1;
+	checksum = 0;
+	scarray = (uint16_t *)sc;
+
+	for (i = 0; i < maxaddr; i++)
+		checksum = checksum + scarray[i];
+	if (checksum == 0
+	 || (checksum & 0xFFFF) != sc->checksum) {
+		return (0);
+	} else {
+		return(1);
+	}
+}