[U-Boot] [PATCH 3/3] atmel_df_pow2: standalone to convert dataflashes to pow2

[Mike Frysinger <vapier@gentoo.org>]

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 +
 examples/standalone/Makefile        |    1 +
 examples/standalone/atmel_df_pow2.c |  209 +++++++++++++++++++++++++++++++++++
 3 files changed, 211 insertions(+), 0 deletions(-)
 create mode 100644 examples/standalone/atmel_df_pow2.c

diff --git a/examples/standalone/.gitignore b/examples/standalone/.gitignore
index 0d1864c..7b783fc 100644
--- a/examples/standalone/.gitignore
+++ b/examples/standalone/.gitignore
@@ -1,4 +1,5 @@
 /82559_eeprom
+/atmel_df_pow2
 /hello_world
 /interrupt
 /mem_to_mem_idma2intr
diff --git a/examples/standalone/Makefile b/examples/standalone/Makefile
index 6c1e8b7..5e2f2bc 100644
--- a/examples/standalone/Makefile
+++ b/examples/standalone/Makefile
@@ -30,6 +30,7 @@ ELF-y        := hello_world
 
 ELF-$(CONFIG_SMC91111)           += smc91111_eeprom
 ELF-$(CONFIG_SMC911X)            += smc911x_eeprom
+ELF-$(CONFIG_SPI_FLASH_ATMEL)    += atmel_df_pow2
 ELF-i386                         += 82559_eeprom
 ELF-mpc5xxx                      += interrupt
 ELF-mpc8xx                       += test_burst timer
diff --git a/examples/standalone/atmel_df_pow2.c b/examples/standalone/atmel_df_pow2.c
new file mode 100644
index 0000000..db0cd69
--- /dev/null
+++ b/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@%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);
+	}
+}
-- 
1.6.4.2