arch/powerpc/cpu/ppc4xx/ecc.c

   1 /*
   2  *    Copyright (c) 2008 Nuovation System Designs, LLC
   3  *      Grant Erickson <gerickson@nuovations.com>
   4  *
   5  *    (C) Copyright 2005-2009
   6  *    Stefan Roese, DENX Software Engineering, sr@denx.de.
   7  *
   8  *    (C) Copyright 2002
   9  *    Jun Gu, Artesyn Technology, jung@artesyncp.com
  10  *
  11  *    (C) Copyright 2001
  12  *    Bill Hunter, Wave 7 Optics, williamhunter@attbi.com
  13  *
  14  *    See file CREDITS for list of people who contributed to this
  15  *    project.
  16  *
  17  *    This program is free software; you can redistribute it and/or
  18  *    modify it under the terms of the GNU General Public License as
  19  *    published by the Free Software Foundation; either version 2 of
  20  *    the License, or (at your option) any later version.
  21  *
  22  *    This program is distributed in the hope that it will abe useful,
  23  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  25  *    GNU General Public License for more details.
  26  *
  27  *    You should have received a copy of the GNU General Public License
  28  *    along with this program; if not, write to the Free Software
  29  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  30  *    MA 02111-1307 USA
  31  *
  32  *    Description:
  33  *      This file implements generic DRAM ECC initialization for
  34  *      PowerPC processors using a SDRAM DDR/DDR2 controller,
  35  *      including the 405EX(r), 440GP/GX/EP/GR, 440SP(E), and
  36  *      460EX/GT.
  37  */
  38
  39 #include <common.h>
  40 #include <ppc4xx.h>
  41 #include <ppc_asm.tmpl>
  42 #include <ppc_defs.h>
  43 #include <asm/processor.h>
  44 #include <asm/io.h>
  45 #include <asm/mmu.h>
  46 #include <asm/cache.h>
  47
  48 #include "ecc.h"
  49
  50 #if defined(CONFIG_SDRAM_PPC4xx_IBM_DDR) || \
  51     defined(CONFIG_SDRAM_PPC4xx_IBM_DDR2)
  52 #if defined(CONFIG_DDR_ECC) || defined(CONFIG_SDRAM_ECC)
  53
  54 #if defined(CONFIG_405EX)
  55 /*
  56  * Currently only 405EX uses 16bit data bus width as an alternative
  57  * option to 32bit data width (SDRAM0_MCOPT1_WDTH)
  58  */
  59 #define SDRAM_DATA_ALT_WIDTH    2
  60 #else
  61 #define SDRAM_DATA_ALT_WIDTH    8
  62 #endif
  63
  64 static void wait_ddr_idle(void)
  65 {
  66         u32 val;
  67
  68         do {
  69                 mfsdram(SDRAM_MCSTAT, val);
  70         } while ((val & SDRAM_MCSTAT_IDLE_MASK) == SDRAM_MCSTAT_IDLE_NOT);
  71 }
  72
  73 static void program_ecc_addr(unsigned long start_address,
  74                              unsigned long num_bytes,
  75                              unsigned long tlb_word2_i_value)
  76 {
  77         unsigned long current_address;
  78         unsigned long end_address;
  79         unsigned long address_increment;
  80         unsigned long mcopt1;
  81         char str[] = "ECC generation -";
  82         char slash[] = "\\|/-\\|/-";
  83         int loop = 0;
  84         int loopi = 0;
  85
  86         current_address = start_address;
  87         mfsdram(SDRAM_MCOPT1, mcopt1);
  88         if ((mcopt1 & SDRAM_MCOPT1_MCHK_MASK) != SDRAM_MCOPT1_MCHK_NON) {
  89                 mtsdram(SDRAM_MCOPT1,
  90                         (mcopt1 & ~SDRAM_MCOPT1_MCHK_MASK) | SDRAM_MCOPT1_MCHK_GEN);
  91                 sync();
  92                 eieio();
  93                 wait_ddr_idle();
  94
  95                 puts(str);
  96
  97 #ifdef CONFIG_440
  98                 if (tlb_word2_i_value == TLB_WORD2_I_ENABLE) {
  99 #endif
 100                         /* ECC bit set method for non-cached memory */
 101                         if ((mcopt1 & SDRAM_MCOPT1_DMWD_MASK) == SDRAM_MCOPT1_DMWD_32)
 102                                 address_increment = 4;
 103                         else
 104                                 address_increment = SDRAM_DATA_ALT_WIDTH;
 105                         end_address = current_address + num_bytes;
 106
 107                         while (current_address < end_address) {
 108                                 *((unsigned long *)current_address) = 0;
 109                                 current_address += address_increment;
 110
 111                                 if ((loop++ % (2 << 20)) == 0) {
 112                                         putc('\b');
 113                                         putc(slash[loopi++ % 8]);
 114                                 }
 115                         }
 116 #ifdef CONFIG_440
 117                 } else {
 118                         /* ECC bit set method for cached memory */
 119                         dcbz_area(start_address, num_bytes);
 120                         /* Write modified dcache lines back to memory */
 121                         clean_dcache_range(start_address, start_address + num_bytes);
 122                 }
 123 #endif /* CONFIG_440 */
 124
 125                 blank_string(strlen(str));
 126
 127                 sync();
 128                 eieio();
 129                 wait_ddr_idle();
 130
 131                 /* clear ECC error repoting registers */
 132                 mtsdram(SDRAM_ECCES, 0xffffffff);
 133                 mtdcr(0x4c, 0xffffffff);
 134
 135                 mtsdram(SDRAM_MCOPT1,
 136                         (mcopt1 & ~SDRAM_MCOPT1_MCHK_MASK) | SDRAM_MCOPT1_MCHK_CHK_REP);
 137                 sync();
 138                 eieio();
 139                 wait_ddr_idle();
 140         }
 141 }
 142
 143 #if defined(CONFIG_SDRAM_PPC4xx_IBM_DDR)
 144 void ecc_init(unsigned long * const start, unsigned long size)
 145 {
 146         /*
 147          * Init ECC with cache disabled (on PPC's with IBM DDR
 148          * controller (non DDR2), not tested with cache enabled yet
 149          */
 150         program_ecc_addr((u32)start, size, TLB_WORD2_I_ENABLE);
 151 }
 152 #endif
 153
 154 #if defined(CONFIG_SDRAM_PPC4xx_IBM_DDR2)
 155 void do_program_ecc(unsigned long tlb_word2_i_value)
 156 {
 157         unsigned long mcopt1;
 158         unsigned long mcopt2;
 159         unsigned long mcstat;
 160         phys_size_t memsize = sdram_memsize();
 161
 162         if (memsize > CONFIG_MAX_MEM_MAPPED) {
 163                 printf("\nWarning: Can't enable ECC on systems with more than 2GB of SDRAM!\n");
 164                 return;
 165         }
 166
 167         mfsdram(SDRAM_MCOPT1, mcopt1);
 168         mfsdram(SDRAM_MCOPT2, mcopt2);
 169
 170         if ((mcopt1 & SDRAM_MCOPT1_MCHK_MASK) != SDRAM_MCOPT1_MCHK_NON) {
 171                 /* DDR controller must be enabled and not in self-refresh. */
 172                 mfsdram(SDRAM_MCSTAT, mcstat);
 173                 if (((mcopt2 & SDRAM_MCOPT2_DCEN_MASK) == SDRAM_MCOPT2_DCEN_ENABLE)
 174                     && ((mcopt2 & SDRAM_MCOPT2_SREN_MASK) == SDRAM_MCOPT2_SREN_EXIT)
 175                     && ((mcstat & (SDRAM_MCSTAT_MIC_MASK | SDRAM_MCSTAT_SRMS_MASK))
 176                         == (SDRAM_MCSTAT_MIC_COMP | SDRAM_MCSTAT_SRMS_NOT_SF))) {
 177
 178                         program_ecc_addr(0, memsize, tlb_word2_i_value);
 179                 }
 180         }
 181 }
 182 #endif
 183
 184 #endif /* defined(CONFIG_DDR_ECC) || defined(CONFIG_SDRAM_ECC) */
 185 #endif /* defined(CONFIG_SDRAM_PPC4xx_IBM_DDR)... */