arch/arm/mach-omap2/gpmc-nand.c

   1 /*
   2  * gpmc-nand.c
   3  *
   4  * Copyright (C) 2009 Texas Instruments
   5  * Vimal Singh <vimalsingh@ti.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/io.h>
  15 #include <linux/mtd/nand.h>
  16
  17 #include <asm/mach/flash.h>
  18
  19 #include <plat/nand.h>
  20 #include <plat/board.h>
  21 #include <plat/gpmc.h>
  22
  23 static struct resource gpmc_nand_resource = {
  24         .flags          = IORESOURCE_MEM,
  25 };
  26
  27 static struct platform_device gpmc_nand_device = {
  28         .name           = "omap2-nand",
  29         .id             = 0,
  30         .num_resources  = 1,
  31         .resource       = &gpmc_nand_resource,
  32 };
  33
  34 static int omap2_nand_gpmc_retime(struct omap_nand_platform_data *gpmc_nand_data)
  35 {
  36         struct gpmc_timings t;
  37         int err;
  38
  39         if (!gpmc_nand_data->gpmc_t)
  40                 return 0;
  41
  42         memset(&t, 0, sizeof(t));
  43         t.sync_clk = gpmc_nand_data->gpmc_t->sync_clk;
  44         t.cs_on = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_on);
  45         t.adv_on = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->adv_on);
  46
  47         /* Read */
  48         t.adv_rd_off = gpmc_round_ns_to_ticks(
  49                                 gpmc_nand_data->gpmc_t->adv_rd_off);
  50         t.oe_on  = t.adv_on;
  51         t.access = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->access);
  52         t.oe_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->oe_off);
  53         t.cs_rd_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_rd_off);
  54         t.rd_cycle  = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->rd_cycle);
  55
  56         /* Write */
  57         t.adv_wr_off = gpmc_round_ns_to_ticks(
  58                                 gpmc_nand_data->gpmc_t->adv_wr_off);
  59         t.we_on  = t.oe_on;
  60         if (cpu_is_omap34xx()) {
  61             t.wr_data_mux_bus = gpmc_round_ns_to_ticks(
  62                                 gpmc_nand_data->gpmc_t->wr_data_mux_bus);
  63             t.wr_access = gpmc_round_ns_to_ticks(
  64                                 gpmc_nand_data->gpmc_t->wr_access);
  65         }
  66         t.we_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->we_off);
  67         t.cs_wr_off = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->cs_wr_off);
  68         t.wr_cycle  = gpmc_round_ns_to_ticks(gpmc_nand_data->gpmc_t->wr_cycle);
  69
  70         /* Configure GPMC */
  71         if (gpmc_nand_data->devsize == NAND_BUSWIDTH_16)
  72                 gpmc_cs_configure(gpmc_nand_data->cs, GPMC_CONFIG_DEV_SIZE, 1);
  73         else
  74                 gpmc_cs_configure(gpmc_nand_data->cs, GPMC_CONFIG_DEV_SIZE, 0);
  75         gpmc_cs_configure(gpmc_nand_data->cs,
  76                         GPMC_CONFIG_DEV_TYPE, GPMC_DEVICETYPE_NAND);
  77         err = gpmc_cs_set_timings(gpmc_nand_data->cs, &t);
  78         if (err)
  79                 return err;
  80
  81         return 0;
  82 }
  83
  84 int __devinit gpmc_nand_init(struct omap_nand_platform_data *gpmc_nand_data)
  85 {
  86         int err = 0;
  87         u8 cs = 0;
  88         struct device *dev = &gpmc_nand_device.dev;
  89
  90         /* if cs not provided, find out the chip-select on which NAND exist */
  91         if (gpmc_nand_data->cs > GPMC_CS_NUM)
  92                 while (cs < GPMC_CS_NUM) {
  93                         u32 ret = 0;
  94                         ret = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
  95
  96                         if ((ret & 0xC00) == 0x800) {
  97                                 printk(KERN_INFO "Found NAND on CS%d\n", cs);
  98                                 gpmc_nand_data->cs = cs;
  99                                 break;
 100                         }
 101                         cs++;
 102                 }
 103
 104         if (gpmc_nand_data->cs > GPMC_CS_NUM) {
 105                 printk(KERN_INFO "NAND: Unable to find configuration "
 106                                  "in GPMC\n ");
 107                 return -ENODEV;
 108         }
 109
 110         gpmc_nand_device.dev.platform_data = gpmc_nand_data;
 111
 112         printk(KERN_INFO "Registering NAND on CS%d\n", gpmc_nand_data->cs);
 113
 114         err = gpmc_cs_request(gpmc_nand_data->cs, NAND_IO_SIZE,
 115                                 &gpmc_nand_data->phys_base);
 116         if (err < 0) {
 117                 dev_err(dev, "Cannot request GPMC CS\n");
 118                 return err;
 119         }
 120
 121          /* Set timings in GPMC */
 122         err = omap2_nand_gpmc_retime(gpmc_nand_data);
 123         if (err < 0) {
 124                 dev_err(dev, "Unable to set gpmc timings: %d\n", err);
 125                 return err;
 126         }
 127
 128         /* Enable RD PIN Monitoring Reg */
 129         if (gpmc_nand_data->dev_ready) {
 130                 gpmc_cs_configure(gpmc_nand_data->cs, GPMC_CONFIG_RDY_BSY, 1);
 131         }
 132
 133         err = platform_device_register(&gpmc_nand_device);
 134         if (err < 0) {
 135                 dev_err(dev, "Unable to register NAND device\n");
 136                 goto out_free_cs;
 137         }
 138
 139         return 0;
 140
 141 out_free_cs:
 142         gpmc_cs_free(gpmc_nand_data->cs);
 143
 144         return err;
 145 }