board/dave/PPChameleonEVB/nand.c

   1 /*
   2  * (C) Copyright 2006 DENX Software Engineering
   3  *
   4  * See file CREDITS for list of people who contributed to this
   5  * project.
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 of
  10  * the License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  20  * MA 02111-1307 USA
  21  */
  22
  23 #include <common.h>
  24 #include <asm/io.h>
  25
  26 #if defined(CONFIG_CMD_NAND)
  27
  28 #include <nand.h>
  29
  30 /*
  31  * hardware specific access to control-lines
  32  * function borrowed from Linux 2.6 (drivers/mtd/nand/ppchameleonevb.c)
  33  */
  34 static void ppchameleonevb_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  35 {
  36         struct nand_chip *this = mtd->priv;
  37         ulong base = (ulong) this->IO_ADDR_W;
  38
  39         if (ctrl & NAND_CTRL_CHANGE) {
  40                 if ( ctrl & NAND_CLE )
  41                         MACRO_NAND_CTL_SETCLE((unsigned long)base);
  42                 else
  43                         MACRO_NAND_CTL_CLRCLE((unsigned long)base);
  44                 if ( ctrl & NAND_ALE )
  45                         MACRO_NAND_CTL_CLRCLE((unsigned long)base);
  46                 else
  47                         MACRO_NAND_CTL_CLRALE((unsigned long)base);
  48                 if ( ctrl & NAND_NCE )
  49                         MACRO_NAND_ENABLE_CE((unsigned long)base);
  50                 else
  51                         MACRO_NAND_DISABLE_CE((unsigned long)base);
  52         }
  53
  54         if (cmd != NAND_CMD_NONE)
  55                 writeb(cmd, this->IO_ADDR_W);
  56 }
  57
  58
  59 /*
  60  * read device ready pin
  61  * function +/- borrowed from Linux 2.6 (drivers/mtd/nand/ppchameleonevb.c)
  62  */
  63 static int ppchameleonevb_device_ready(struct mtd_info *mtdinfo)
  64 {
  65         struct nand_chip *this = mtdinfo->priv;
  66         ulong rb_gpio_pin;
  67
  68         /* use the base addr to find out which chip are we dealing with */
  69         switch((ulong) this->IO_ADDR_W) {
  70         case CONFIG_SYS_NAND0_BASE:
  71                 rb_gpio_pin = CONFIG_SYS_NAND0_RDY;
  72                 break;
  73         case CONFIG_SYS_NAND1_BASE:
  74                 rb_gpio_pin = CONFIG_SYS_NAND1_RDY;
  75                 break;
  76         default: /* this should never happen */
  77                 return 0;
  78                 break;
  79         }
  80
  81         if (in32(GPIO0_IR) & rb_gpio_pin)
  82                 return 1;
  83         return 0;
  84 }
  85
  86
  87 /*
  88  * Board-specific NAND initialization. The following members of the
  89  * argument are board-specific (per include/linux/mtd/nand.h):
  90  * - IO_ADDR_R?: address to read the 8 I/O lines of the flash device
  91  * - IO_ADDR_W?: address to write the 8 I/O lines of the flash device
  92  * - cmd_ctrl: hardwarespecific function for accesing control-lines
  93  * - dev_ready: hardwarespecific function for  accesing device ready/busy line
  94  * - enable_hwecc?: function to enable (reset)  hardware ecc generator. Must
  95  *   only be provided if a hardware ECC is available
  96  * - ecc.mode: mode of ecc, see defines
  97  * - chip_delay: chip dependent delay for transfering data from array to
  98  *   read regs (tR)
  99  * - options: various chip options. They can partly be set to inform
 100  *   nand_scan about special functionality. See the defines for further
 101  *   explanation
 102  * Members with a "?" were not set in the merged testing-NAND branch,
 103  * so they are not set here either.
 104  */
 105 int board_nand_init(struct nand_chip *nand)
 106 {
 107
 108         nand->cmd_ctrl = ppchameleonevb_hwcontrol;
 109         nand->dev_ready = ppchameleonevb_device_ready;
 110         nand->ecc.mode = NAND_ECC_SOFT;
 111         nand->chip_delay = NAND_BIG_DELAY_US;
 112         nand->options = NAND_SAMSUNG_LP_OPTIONS;
 113         return 0;
 114 }
 115 #endif