atmel_df_pow2: standalone to convert dataflashes to pow2

Atmel DataFlashes by default operate with pages that are slightly bigger
than normal binary sizes (i.e. many are 1056 byte pages rather than 1024
bytes).  However, they also have a "power of 2" mode where the pages show
up with the normal binary size.  The latter mode is required in order to
boot with a Blackfin processor, so many people wish to convert their
DataFlashes on their development systems to this mode.  This standalone
application does just that.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

examples/standalone/.gitignore

@@ -1,4 +1,5 @@
 /82559_eeprom
+/atmel_df_pow2
 /hello_world
 /interrupt
 /mem_to_mem_idma2intr

examples/standalone/Makefile

@@ -86,6 +86,10 @@ ELF	= hello_world
 SREC	= hello_world.srec
 BIN	= hello_world.bin
 
+ELF	+= atmel_df_pow2
+SREC	+= atmel_df_pow2.srec
+BIN	+= atmel_df_pow2.bin
+
 ifeq ($(CPU),mpc8xx)
 ELF	+= test_burst
 SREC	+= test_burst.srec

examples/standalone/atmel_df_pow2.c

@@ -0,0 +1,209 @@
+/*
+ * atmel_df_pow2.c - convert Atmel Dataflashes to Power of 2 mode
+ *
+ * Copyright 2009 Analog Devices Inc.
+ *
+ * Licensed under the 2-clause BSD.
+ */
+
+#include <common.h>
+#include <exports.h>
+
+#define CMD_ID    0x9f
+#define CMD_STAT  0xd7
+#define CMD_CFG   0x3d
+
+static int flash_cmd(struct spi_slave *slave, uchar cmd, uchar *buf, int len)
+{
+	buf[0] = cmd;
+	return spi_xfer(slave, 8 * len, buf, buf, SPI_XFER_BEGIN | SPI_XFER_END);
+}
+
+static int flash_status(struct spi_slave *slave)
+{
+	uchar buf[2];
+	if (flash_cmd(slave, CMD_STAT, buf, sizeof(buf)))
+		return -1;
+	return buf[1];
+}
+
+static int flash_set_pow2(struct spi_slave *slave)
+{
+	int ret;
+	uchar buf[4];
+
+	buf[1] = 0x2a;
+	buf[2] = 0x80;
+	buf[3] = 0xa6;
+
+	ret = flash_cmd(slave, CMD_CFG, buf, sizeof(buf));
+	if (ret)
+		return ret;
+
+	/* wait Tp, or 6 msec */
+	udelay(6000);
+
+	ret = flash_status(slave);
+	if (ret == -1)
+		return 1;
+
+	return ret & 0x1 ? 0 : 1;
+}
+
+static int flash_check(struct spi_slave *slave)
+{
+	int ret;
+	uchar buf[4];
+
+	ret = flash_cmd(slave, CMD_ID, buf, sizeof(buf));
+	if (ret)
+		return ret;
+
+	if (buf[1] != 0x1F) {
+		printf("atmel flash not found (id[0] = %#x)\n", buf[1]);
+		return 1;
+	}
+
+	if ((buf[2] >> 5) != 0x1) {
+		printf("AT45 flash not found (id[0] = %#x)\n", buf[2]);
+		return 2;
+	}
+
+	return 0;
+}
+
+static char *getline(void)
+{
+	static char buffer[100];
+	char c;
+	size_t i;
+
+	i = 0;
+	while (1) {
+		buffer[i] = '\0';
+
+		c = getc();
+
+		switch (c) {
+		case '\r':	/* Enter/Return key */
+		case '\n':
+			puts("\n");
+			return buffer;
+
+		case 0x03:	/* ^C - break */
+			return NULL;
+
+		case 0x5F:
+		case 0x08:	/* ^H  - backspace */
+		case 0x7F:	/* DEL - backspace */
+			if (i) {
+				puts("\b \b");
+				i--;
+			}
+			break;
+
+		default:
+			/* Ignore control characters */
+			if (c < 0x20)
+				break;
+			/* Queue up all other characters */
+			buffer[i++] = c;
+			printf("%c", c);
+			break;
+		}
+	}
+}
+
+int atmel_df_pow2(int argc, char *argv[])
+{
+	/* Print the ABI version */
+	app_startup(argv);
+	if (XF_VERSION != get_version()) {
+		printf("Expects ABI version %d\n", XF_VERSION);
+		printf("Actual U-Boot ABI version %lu\n", get_version());
+		printf("Can't run\n\n");
+		return 1;
+	}
+
+	spi_init();
+
+	while (1) {
+		struct spi_slave *slave;
+		char *line, *p;
+		int bus, cs, status;
+
+		puts("\nenter the [BUS:]CS of the SPI flash: ");
+		line = getline();
+
+		/* CTRL+C */
+		if (!line)
+			return 0;
+		if (line[0] == '\0')
+			continue;
+
+		bus = cs = simple_strtoul(line, &p, 10);
+		if (*p) {
+			if (*p == ':') {
+				++p;
+				cs = simple_strtoul(p, &p, 10);
+			}
+			if (*p) {
+				puts("invalid format, please try again\n");
+				continue;
+			}
+		} else
+			bus = 0;
+
+		printf("\ngoing to work with dataflash at %i:%i\n", bus, cs);
+
+		/* use a low speed -- it'll work with all devices, and
+		 * speed here doesn't really matter.
+		 */
+		slave = spi_setup_slave(bus, cs, 1000, SPI_MODE_3);
+		if (!slave) {
+			puts("unable to setup slave\n");
+			continue;
+		}
+
+		if (spi_claim_bus(slave)) {
+			spi_free_slave(slave);
+			continue;
+		}
+
+		if (flash_check(slave)) {
+			puts("no flash found\n");
+			goto done;
+		}
+
+		status = flash_status(slave);
+		if (status == -1) {
+			puts("unable to read status register\n");
+			goto done;
+		}
+		if (status & 0x1) {
+			puts("flash is already in power-of-2 mode!\n");
+			goto done;
+		}
+
+		puts("are you sure you wish to set power-of-2 mode?\n");
+		puts("this operation is permanent and irreversible\n");
+		printf("enter YES to continue: ");
+		line = getline();
+		if (!line || strcmp(line, "YES"))
+			goto done;
+
+		if (flash_set_pow2(slave)) {
+			puts("setting pow2 mode failed\n");
+			goto done;
+		}
+
+		puts(
+			"Configuration should be updated now.  You will have to\n"
+			"power cycle the part in order to finish the conversion.\n"
+		);
+
+ done:
+		spi_release_bus(slave);
+		spi_free_slave(slave);
+	}
+}