nand_spl/nand_boot_fsl_elbc.c

   1 /*
   2  * NAND boot for Freescale Enhanced Local Bus Controller, Flash Control Machine
   3  *
   4  * (C) Copyright 2006-2008
   5  * Stefan Roese, DENX Software Engineering, sr@denx.de.
   6  *
   7  * Copyright (c) 2008 Freescale Semiconductor, Inc.
   8  * Author: Scott Wood <scottwood@freescale.com>
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License as
  12  * published by the Free Software Foundation; either version 2 of
  13  * the License, or (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  23  * MA 02111-1307 USA
  24  */
  25
  26 #include <common.h>
  27 #include <asm/io.h>
  28 #include <asm/fsl_lbc.h>
  29 #include <linux/mtd/nand.h>
  30
  31 #define WINDOW_SIZE 8192
  32
  33 static void nand_wait(void)
  34 {
  35         fsl_lbc_t *regs = LBC_BASE_ADDR;
  36
  37         for (;;) {
  38                 uint32_t status = in_be32(&regs->ltesr);
  39
  40                 if (status == 1)
  41                         return;
  42
  43                 if (status & 1) {
  44                         puts("read failed (ltesr)\n");
  45                         for (;;);
  46                 }
  47         }
  48 }
  49
  50 static void nand_load(unsigned int offs, int uboot_size, uchar *dst)
  51 {
  52         fsl_lbc_t *regs = LBC_BASE_ADDR;
  53         uchar *buf = (uchar *)CONFIG_SYS_NAND_BASE;
  54         int large = in_be32(&regs->bank[0].or) & OR_FCM_PGS;
  55         int block_shift = large ? 17 : 14;
  56         int block_size = 1 << block_shift;
  57         int page_size = large ? 2048 : 512;
  58         int bad_marker = large ? page_size + 0 : page_size + 5;
  59         int fmr = (15 << FMR_CWTO_SHIFT) | (2 << FMR_AL_SHIFT) | 2;
  60         int pos = 0;
  61
  62         if (offs & (block_size - 1)) {
  63                 puts("bad offset\n");
  64                 for (;;);
  65         }
  66
  67         if (large) {
  68                 fmr |= FMR_ECCM;
  69                 out_be32(&regs->fcr, (NAND_CMD_READ0 << FCR_CMD0_SHIFT) |
  70                                      (NAND_CMD_READSTART << FCR_CMD1_SHIFT));
  71                 out_be32(&regs->fir,
  72                          (FIR_OP_CW0 << FIR_OP0_SHIFT) |
  73                          (FIR_OP_CA  << FIR_OP1_SHIFT) |
  74                          (FIR_OP_PA  << FIR_OP2_SHIFT) |
  75                          (FIR_OP_CW1 << FIR_OP3_SHIFT) |
  76                          (FIR_OP_RBW << FIR_OP4_SHIFT));
  77         } else {
  78                 out_be32(&regs->fcr, NAND_CMD_READ0 << FCR_CMD0_SHIFT);
  79                 out_be32(&regs->fir,
  80                          (FIR_OP_CW0 << FIR_OP0_SHIFT) |
  81                          (FIR_OP_CA  << FIR_OP1_SHIFT) |
  82                          (FIR_OP_PA  << FIR_OP2_SHIFT) |
  83                          (FIR_OP_RBW << FIR_OP3_SHIFT));
  84         }
  85
  86         out_be32(&regs->fbcr, 0);
  87         clrsetbits_be32(&regs->bank[0].br, BR_DECC, BR_DECC_CHK_GEN);
  88
  89         while (pos < uboot_size) {
  90                 int i = 0;
  91                 out_be32(&regs->fbar, offs >> block_shift);
  92
  93                 do {
  94                         int j;
  95                         unsigned int page_offs = (offs & (block_size - 1)) << 1;
  96
  97                         out_be32(&regs->ltesr, ~0);
  98                         out_be32(&regs->lteatr, 0);
  99                         out_be32(&regs->fpar, page_offs);
 100                         out_be32(&regs->fmr, fmr);
 101                         out_be32(&regs->lsor, 0);
 102                         nand_wait();
 103
 104                         page_offs %= WINDOW_SIZE;
 105
 106                         /*
 107                          * If either of the first two pages are marked bad,
 108                          * continue to the next block.
 109                          */
 110                         if (i++ < 2 && buf[page_offs + bad_marker] != 0xff) {
 111                                 puts("skipping\n");
 112                                 offs = (offs + block_size) & ~(block_size - 1);
 113                                 pos &= ~(block_size - 1);
 114                                 break;
 115                         }
 116
 117                         for (j = 0; j < page_size; j++)
 118                                 dst[pos + j] = buf[page_offs + j];
 119
 120                         pos += page_size;
 121                         offs += page_size;
 122                 } while ((offs & (block_size - 1)) && (pos < uboot_size));
 123         }
 124 }
 125
 126 /*
 127  * The main entry for NAND booting. It's necessary that SDRAM is already
 128  * configured and available since this code loads the main U-Boot image
 129  * from NAND into SDRAM and starts it from there.
 130  */
 131 void nand_boot(void)
 132 {
 133         __attribute__((noreturn)) void (*uboot)(void);
 134
 135         /*
 136          * Load U-Boot image from NAND into RAM
 137          */
 138         nand_load(CONFIG_SYS_NAND_U_BOOT_OFFS, CONFIG_SYS_NAND_U_BOOT_SIZE,
 139                   (uchar *)CONFIG_SYS_NAND_U_BOOT_DST);
 140
 141         /*
 142          * Jump to U-Boot image
 143          */
 144         puts("transfering control\n");
 145         /*
 146          * Clean d-cache and invalidate i-cache, to
 147          * make sure that no stale data is executed.
 148          */
 149         flush_cache(CONFIG_SYS_NAND_U_BOOT_DST, CONFIG_SYS_NAND_U_BOOT_SIZE);
 150         uboot = (void *)CONFIG_SYS_NAND_U_BOOT_START;
 151         uboot();
 152 }