--- /dev/null
+/*
+ * (C) Copyright 2011
+ * Texas Instruments, <www.ti.com>
+ *
+ * Author :
+ * Tom Rini <trini@ti.com>
+ *
+ * Initial Code from:
+ * Richard Woodruff <r-woodruff2@ti.com>
+ * Jian Zhang <jzhang@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <linux/mtd/nand.h>
+#include <asm/io.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/arch/mem.h>
+
+static struct gpmc *gpmc_config = (struct gpmc *)GPMC_BASE;
+
+/* nand_command: Send a flash command to the flash chip */
+static void nand_command(u8 command)
+{
+ writeb(command, &gpmc_config->cs[0].nand_cmd);
+
+ if (command == NAND_CMD_RESET) {
+ unsigned char ret_val;
+ writeb(NAND_CMD_STATUS, &gpmc_config->cs[0].nand_cmd);
+ do {
+ /* Wait until ready */
+ ret_val = readl(&gpmc_config->cs[0].nand_dat);
+ } while ((ret_val & NAND_STATUS_READY) != NAND_STATUS_READY);
+ }
+}
+
+/*
+ * Many boards will want to know the results of the NAND_CMD_READID command
+ * in order to decide what to do about DDR initialization. This function
+ * allows us to do that very early and to pass those results back to the
+ * board so it can make whatever decisions need to be made.
+ */
+void identify_nand_chip(int *mfr, int *id)
+{
+ /* Make sure that we have setup GPMC for NAND correctly. */
+ writel(M_NAND_GPMC_CONFIG1, &gpmc_config->cs[0].config1);
+ writel(M_NAND_GPMC_CONFIG2, &gpmc_config->cs[0].config2);
+ writel(M_NAND_GPMC_CONFIG3, &gpmc_config->cs[0].config3);
+ writel(M_NAND_GPMC_CONFIG4, &gpmc_config->cs[0].config4);
+ writel(M_NAND_GPMC_CONFIG5, &gpmc_config->cs[0].config5);
+ writel(M_NAND_GPMC_CONFIG6, &gpmc_config->cs[0].config6);
+
+ /*
+ * Enable the config. The CS size goes in bits 11:8. We set
+ * bit 6 to enable the CS and the base address goes into bits 5:0.
+ */
+ writel((GPMC_SIZE_128M << 8) | (GPMC_CS_ENABLE << 6) |
+ ((NAND_BASE >> 24) & GPMC_BASEADDR_MASK),
+ &gpmc_config->cs[0].config7);
+
+ sdelay(2000);
+
+ /* Issue a RESET and then READID */
+ nand_command(NAND_CMD_RESET);
+ nand_command(NAND_CMD_READID);
+
+ /* Set the address to read to 0x0 */
+ writeb(0x0, &gpmc_config->cs[0].nand_adr);
+
+ /* Read off the manufacturer and device id. */
+ *mfr = readb(&gpmc_config->cs[0].nand_dat);
+ *id = readb(&gpmc_config->cs[0].nand_dat);
+}