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/*
* (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);
}
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