--- /dev/null
+/*
+ * 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);
+ }
+}