mpc83xx: implement board_add_ram_info

[people/ms/u-boot.git] / cpu / mpc83xx / spd_sdram.c

/*
 * (C) Copyright 2006 Freescale Semiconductor, Inc.
 *
 * (C) Copyright 2006
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * Copyright (C) 2004-2006 Freescale Semiconductor, Inc.
 * (C) Copyright 2003 Motorola Inc.
 * Xianghua Xiao (X.Xiao@motorola.com)
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * 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 <asm/processor.h>
#include <i2c.h>
#include <spd.h>
#include <asm/mmu.h>
#include <spd_sdram.h>

void board_add_ram_info(int use_default)
{
        volatile immap_t *immap = (immap_t *) CFG_IMMR;
        volatile ddr83xx_t *ddr = &immap->ddr;

        printf(" (DDR%d", ((ddr->sdram_cfg & SDRAM_CFG_SDRAM_TYPE_MASK)
                           >> SDRAM_CFG_SDRAM_TYPE_SHIFT) - 1);

        if (ddr->sdram_cfg & SDRAM_CFG_32_BE)
                puts(", 32-bit");
        else
                puts(", 64-bit");

        if (ddr->sdram_cfg & SDRAM_CFG_ECC_EN)
                puts(", ECC on)");
        else
                puts(", ECC off)");

#if defined(CFG_LB_SDRAM) && defined(CFG_LBC_SDRAM_SIZE)
        puts("\nSDRAM: ");
        print_size (CFG_LBC_SDRAM_SIZE * 1024 * 1024, " (local bus)");
#endif
}

#ifdef CONFIG_SPD_EEPROM

DECLARE_GLOBAL_DATA_PTR;

#if defined(CONFIG_DDR_ECC) && !defined(CONFIG_ECC_INIT_VIA_DDRC)
extern void dma_init(void);
extern uint dma_check(void);
extern int dma_xfer(void *dest, uint count, void *src);
#endif

#ifndef CFG_READ_SPD
#define CFG_READ_SPD    i2c_read
#endif

/*
 * Convert picoseconds into clock cycles (rounding up if needed).
 */
int
picos_to_clk(int picos)
{
        unsigned int ddr_bus_clk;
        int clks;

        ddr_bus_clk = gd->ddr_clk >> 1;
        clks = picos / (1000000000 / (ddr_bus_clk / 1000));
        if (picos % (1000000000 / (ddr_bus_clk / 1000)) != 0)
                clks++;

        return clks;
}

unsigned int banksize(unsigned char row_dens)
{
        return ((row_dens >> 2) | ((row_dens & 3) << 6)) << 24;
}

int read_spd(uint addr)
{
        return ((int) addr);
}

#undef SPD_DEBUG
#ifdef SPD_DEBUG
static void spd_debug(spd_eeprom_t *spd)
{
        printf ("\nDIMM type:       %-18.18s\n", spd->mpart);
        printf ("SPD size:        %d\n", spd->info_size);
        printf ("EEPROM size:     %d\n", 1 << spd->chip_size);
        printf ("Memory type:     %d\n", spd->mem_type);
        printf ("Row addr:        %d\n", spd->nrow_addr);
        printf ("Column addr:     %d\n", spd->ncol_addr);
        printf ("# of rows:       %d\n", spd->nrows);
        printf ("Row density:     %d\n", spd->row_dens);
        printf ("# of banks:      %d\n", spd->nbanks);
        printf ("Data width:      %d\n",
                        256 * spd->dataw_msb + spd->dataw_lsb);
        printf ("Chip width:      %d\n", spd->primw);
        printf ("Refresh rate:    %02X\n", spd->refresh);
        printf ("CAS latencies:   %02X\n", spd->cas_lat);
        printf ("Write latencies: %02X\n", spd->write_lat);
        printf ("tRP:             %d\n", spd->trp);
        printf ("tRCD:            %d\n", spd->trcd);
        printf ("\n");
}
#endif /* SPD_DEBUG */

long int spd_sdram()
{
        volatile immap_t *immap = (immap_t *)CFG_IMMR;
        volatile ddr83xx_t *ddr = &immap->ddr;
        volatile law83xx_t *ecm = &immap->sysconf.ddrlaw[0];
        spd_eeprom_t spd;
        unsigned int n_ranks;
        unsigned int odt_rd_cfg, odt_wr_cfg;
        unsigned char twr_clk, twtr_clk;
        unsigned int sdram_type;
        unsigned int memsize;
        unsigned int law_size;
        unsigned char caslat, caslat_ctrl;
        unsigned int trfc, trfc_clk, trfc_low, trfc_high;
        unsigned int trcd_clk, trtp_clk;
        unsigned char cke_min_clk;
        unsigned char add_lat, wr_lat;
        unsigned char wr_data_delay;
        unsigned char four_act;
        unsigned char cpo;
        unsigned char burstlen;
        unsigned char odt_cfg, mode_odt_enable;
        unsigned int max_bus_clk;
        unsigned int max_data_rate, effective_data_rate;
        unsigned int ddrc_clk;
        unsigned int refresh_clk;
        unsigned int sdram_cfg;
        unsigned int ddrc_ecc_enable;
        unsigned int pvr = get_pvr();

        /* Read SPD parameters with I2C */
        CFG_READ_SPD(SPD_EEPROM_ADDRESS, 0, 1, (uchar *) & spd, sizeof (spd));
#ifdef SPD_DEBUG
        spd_debug(&spd);
#endif
        /* Check the memory type */
        if (spd.mem_type != SPD_MEMTYPE_DDR && spd.mem_type != SPD_MEMTYPE_DDR2) {
                debug("DDR: Module mem type is %02X\n", spd.mem_type);
                return 0;
        }

        /* Check the number of physical bank */
        if (spd.mem_type == SPD_MEMTYPE_DDR) {
                n_ranks = spd.nrows;
        } else {
                n_ranks = (spd.nrows & 0x7) + 1;
        }

        if (n_ranks > 2) {
                printf("DDR: The number of physical bank is %02X\n", n_ranks);
                return 0;
        }

        /* Check if the number of row of the module is in the range of DDRC */
        if (spd.nrow_addr < 12 || spd.nrow_addr > 15) {
                printf("DDR: Row number is out of range of DDRC, row=%02X\n",
                                                         spd.nrow_addr);
                return 0;
        }

        /* Check if the number of col of the module is in the range of DDRC */
        if (spd.ncol_addr < 8 || spd.ncol_addr > 11) {
                printf("DDR: Col number is out of range of DDRC, col=%02X\n",
                                                         spd.ncol_addr);
                return 0;
        }

#ifdef CFG_DDRCDR_VALUE
        /*
         * Adjust DDR II IO voltage biasing.  It just makes it work.
         */
        if(spd.mem_type == SPD_MEMTYPE_DDR2) {
                immap->sysconf.ddrcdr = CFG_DDRCDR_VALUE;
        }
#endif

        /*
         * ODT configuration recommendation from DDR Controller Chapter.
         */
        odt_rd_cfg = 0;                 /* Never assert ODT */
        odt_wr_cfg = 0;                 /* Never assert ODT */
        if (spd.mem_type == SPD_MEMTYPE_DDR2) {
                odt_wr_cfg = 1;         /* Assert ODT on writes to CSn */
        }

        /* Setup DDR chip select register */
#ifdef CFG_83XX_DDR_USES_CS0
        ddr->csbnds[0].csbnds = (banksize(spd.row_dens) >> 24) - 1;
        ddr->cs_config[0] = ( 1 << 31
                            | (odt_rd_cfg << 20)
                            | (odt_wr_cfg << 16)
                            | (spd.nrow_addr - 12) << 8
                            | (spd.ncol_addr - 8) );
        debug("\n");
        debug("cs0_bnds = 0x%08x\n",ddr->csbnds[0].csbnds);
        debug("cs0_config = 0x%08x\n",ddr->cs_config[0]);

        if (n_ranks == 2) {
                ddr->csbnds[1].csbnds = ( (banksize(spd.row_dens) >> 8)
                                  | ((banksize(spd.row_dens) >> 23) - 1) );
                ddr->cs_config[1] = ( 1<<31
                                    | (odt_rd_cfg << 20)
                                    | (odt_wr_cfg << 16)
                                    | (spd.nrow_addr-12) << 8
                                    | (spd.ncol_addr-8) );
                debug("cs1_bnds = 0x%08x\n",ddr->csbnds[1].csbnds);
                debug("cs1_config = 0x%08x\n",ddr->cs_config[1]);
        }

#else
        ddr->csbnds[2].csbnds = (banksize(spd.row_dens) >> 24) - 1;
        ddr->cs_config[2] = ( 1 << 31
                            | (odt_rd_cfg << 20)
                            | (odt_wr_cfg << 16)
                            | (spd.nrow_addr - 12) << 8
                            | (spd.ncol_addr - 8) );
        debug("\n");
        debug("cs2_bnds = 0x%08x\n",ddr->csbnds[2].csbnds);
        debug("cs2_config = 0x%08x\n",ddr->cs_config[2]);

        if (n_ranks == 2) {
                ddr->csbnds[3].csbnds = ( (banksize(spd.row_dens) >> 8)
                                  | ((banksize(spd.row_dens) >> 23) - 1) );
                ddr->cs_config[3] = ( 1<<31
                                    | (odt_rd_cfg << 20)
                                    | (odt_wr_cfg << 16)
                                    | (spd.nrow_addr-12) << 8
                                    | (spd.ncol_addr-8) );
                debug("cs3_bnds = 0x%08x\n",ddr->csbnds[3].csbnds);
                debug("cs3_config = 0x%08x\n",ddr->cs_config[3]);
        }
#endif

        /*
         * Figure out memory size in Megabytes.
         */
        memsize = n_ranks * banksize(spd.row_dens) / 0x100000;

        /*
         * First supported LAW size is 16M, at LAWAR_SIZE_16M == 23.
         */
        law_size = 19 + __ilog2(memsize);

        /*
         * Set up LAWBAR for all of DDR.
         */
        ecm->bar = ((CFG_DDR_SDRAM_BASE>>12) & 0xfffff);
        ecm->ar  = (LAWAR_EN | LAWAR_TRGT_IF_DDR | (LAWAR_SIZE & law_size));
        debug("DDR:bar=0x%08x\n", ecm->bar);
        debug("DDR:ar=0x%08x\n", ecm->ar);

        /*
         * Find the largest CAS by locating the highest 1 bit
         * in the spd.cas_lat field.  Translate it to a DDR
         * controller field value:
         *
         *      CAS Lat DDR I   DDR II  Ctrl
         *      Clocks  SPD Bit SPD Bit Value
         *      ------- ------- ------- -----
         *      1.0     0               0001
         *      1.5     1               0010
         *      2.0     2       2       0011
         *      2.5     3               0100
         *      3.0     4       3       0101
         *      3.5     5               0110
         *      4.0     6       4       0111
         *      4.5                     1000
         *      5.0             5       1001
         */
        caslat = __ilog2(spd.cas_lat);
        if ((spd.mem_type == SPD_MEMTYPE_DDR)
            && (caslat > 6)) {
                printf("DDR I: Invalid SPD CAS Latency: 0x%x.\n", spd.cas_lat);
                return 0;
        } else if (spd.mem_type == SPD_MEMTYPE_DDR2
                   && (caslat < 2 || caslat > 5)) {
                printf("DDR II: Invalid SPD CAS Latency: 0x%x.\n",
                       spd.cas_lat);
                return 0;
        }
        debug("DDR: caslat SPD bit is %d\n", caslat);

        max_bus_clk = 1000 *10 / (((spd.clk_cycle & 0xF0) >> 4) * 10
                        + (spd.clk_cycle & 0x0f));
        max_data_rate = max_bus_clk * 2;

        debug("DDR:Module maximum data rate is: %dMhz\n", max_data_rate);

        ddrc_clk = gd->ddr_clk / 1000000;
        effective_data_rate = 0;

        if (max_data_rate >= 390 && max_data_rate < 460) { /* it is DDR 400 */
                if (ddrc_clk <= 460 && ddrc_clk > 350) {
                        /* DDR controller clk at 350~460 */
                        effective_data_rate = 400; /* 5ns */
                        caslat = caslat;
                } else if (ddrc_clk <= 350 && ddrc_clk > 280) {
                        /* DDR controller clk at 280~350 */
                        effective_data_rate = 333; /* 6ns */
                        if (spd.clk_cycle2 == 0x60)
                                caslat = caslat - 1;
                        else
                                caslat = caslat;
                } else if (ddrc_clk <= 280 && ddrc_clk > 230) {
                        /* DDR controller clk at 230~280 */
                        effective_data_rate = 266; /* 7.5ns */
                        if (spd.clk_cycle3 == 0x75)
                                caslat = caslat - 2;
                        else if (spd.clk_cycle2 == 0x75)
                                caslat = caslat - 1;
                        else
                                caslat = caslat;
                } else if (ddrc_clk <= 230 && ddrc_clk > 90) {
                        /* DDR controller clk at 90~230 */
                        effective_data_rate = 200; /* 10ns */
                        if (spd.clk_cycle3 == 0xa0)
                                caslat = caslat - 2;
                        else if (spd.clk_cycle2 == 0xa0)
                                caslat = caslat - 1;
                        else
                                caslat = caslat;
                }
        } else if (max_data_rate >= 323) { /* it is DDR 333 */
                if (ddrc_clk <= 350 && ddrc_clk > 280) {
                        /* DDR controller clk at 280~350 */
                        effective_data_rate = 333; /* 6ns */
                        caslat = caslat;
                } else if (ddrc_clk <= 280 && ddrc_clk > 230) {
                        /* DDR controller clk at 230~280 */
                        effective_data_rate = 266; /* 7.5ns */
                        if (spd.clk_cycle2 == 0x75)
                                caslat = caslat - 1;
                        else
                                caslat = caslat;
                } else if (ddrc_clk <= 230 && ddrc_clk > 90) {
                        /* DDR controller clk at 90~230 */
                        effective_data_rate = 200; /* 10ns */
                        if (spd.clk_cycle3 == 0xa0)
                                caslat = caslat - 2;
                        else if (spd.clk_cycle2 == 0xa0)
                                caslat = caslat - 1;
                        else
                                caslat = caslat;
                }
        } else if (max_data_rate >= 256) { /* it is DDR 266 */
                if (ddrc_clk <= 350 && ddrc_clk > 280) {
                        /* DDR controller clk at 280~350 */
                        printf("DDR: DDR controller freq is more than "
                                "max data rate of the module\n");
                        return 0;
                } else if (ddrc_clk <= 280 && ddrc_clk > 230) {
                        /* DDR controller clk at 230~280 */
                        effective_data_rate = 266; /* 7.5ns */
                        caslat = caslat;
                } else if (ddrc_clk <= 230 && ddrc_clk > 90) {
                        /* DDR controller clk at 90~230 */
                        effective_data_rate = 200; /* 10ns */
                        if (spd.clk_cycle2 == 0xa0)
                                caslat = caslat - 1;
                }
        } else if (max_data_rate >= 190) { /* it is DDR 200 */
                if (ddrc_clk <= 350 && ddrc_clk > 230) {
                        /* DDR controller clk at 230~350 */
                        printf("DDR: DDR controller freq is more than "
                                "max data rate of the module\n");
                        return 0;
                } else if (ddrc_clk <= 230 && ddrc_clk > 90) {
                        /* DDR controller clk at 90~230 */
                        effective_data_rate = 200; /* 10ns */
                        caslat = caslat;
                }
        }

        debug("DDR:Effective data rate is: %dMhz\n", effective_data_rate);
        debug("DDR:The MSB 1 of CAS Latency is: %d\n", caslat);

        /*
         * Errata DDR6 work around: input enable 2 cycles earlier.
         * including MPC834x Rev1.0/1.1 and MPC8360 Rev1.1/1.2.
         */
        if(PVR_MAJ(pvr) <= 1 && spd.mem_type == SPD_MEMTYPE_DDR){
                if (caslat == 2)
                        ddr->debug_reg = 0x201c0000; /* CL=2 */
                else if (caslat == 3)
                        ddr->debug_reg = 0x202c0000; /* CL=2.5 */
                else if (caslat == 4)
                        ddr->debug_reg = 0x202c0000; /* CL=3.0 */

                __asm__ __volatile__ ("sync");

                debug("Errata DDR6 (debug_reg=0x%08x)\n", ddr->debug_reg);
        }

        /*
         * Convert caslat clocks to DDR controller value.
         * Force caslat_ctrl to be DDR Controller field-sized.
         */
        if (spd.mem_type == SPD_MEMTYPE_DDR) {
                caslat_ctrl = (caslat + 1) & 0x07;
        } else {
                caslat_ctrl =  (2 * caslat - 1) & 0x0f;
        }

        debug("DDR: effective data rate is %d MHz\n", effective_data_rate);
        debug("DDR: caslat SPD bit is %d, controller field is 0x%x\n",
              caslat, caslat_ctrl);

        /*
         * Timing Config 0.
         * Avoid writing for DDR I.
         */
        if (spd.mem_type == SPD_MEMTYPE_DDR2) {
                unsigned char taxpd_clk = 8;            /* By the book. */
                unsigned char tmrd_clk = 2;             /* By the book. */
                unsigned char act_pd_exit = 2;          /* Empirical? */
                unsigned char pre_pd_exit = 6;          /* Empirical? */

                ddr->timing_cfg_0 = (0
                        | ((act_pd_exit & 0x7) << 20)   /* ACT_PD_EXIT */
                        | ((pre_pd_exit & 0x7) << 16)   /* PRE_PD_EXIT */
                        | ((taxpd_clk & 0xf) << 8)      /* ODT_PD_EXIT */
                        | ((tmrd_clk & 0xf) << 0)       /* MRS_CYC */
                        );
                debug("DDR: timing_cfg_0 = 0x%08x\n", ddr->timing_cfg_0);
        }

        /*
         * For DDR I, WRREC(Twr) and WRTORD(Twtr) are not in SPD,
         * use conservative value.
         * For DDR II, they are bytes 36 and 37, in quarter nanos.
         */

        if (spd.mem_type == SPD_MEMTYPE_DDR) {
                twr_clk = 3;    /* Clocks */
                twtr_clk = 1;   /* Clocks */
        } else {
                twr_clk = picos_to_clk(spd.twr * 250);
                twtr_clk = picos_to_clk(spd.twtr * 250);
        }

        /*
         * Calculate Trfc, in picos.
         * DDR I:  Byte 42 straight up in ns.
         * DDR II: Byte 40 and 42 swizzled some, in ns.
         */
        if (spd.mem_type == SPD_MEMTYPE_DDR) {
                trfc = spd.trfc * 1000;         /* up to ps */
        } else {
                unsigned int byte40_table_ps[8] = {
                        0,
                        250,
                        330,
                        500,
                        660,
                        750,
                        0,
                        0
                };

                trfc = (((spd.trctrfc_ext & 0x1) * 256) + spd.trfc) * 1000
                        + byte40_table_ps[(spd.trctrfc_ext >> 1) & 0x7];
        }
        trfc_clk = picos_to_clk(trfc);

        /*
         * Trcd, Byte 29, from quarter nanos to ps and clocks.
         */
        trcd_clk = picos_to_clk(spd.trcd * 250) & 0x7;

        /*
         * Convert trfc_clk to DDR controller fields.  DDR I should
         * fit in the REFREC field (16-19) of TIMING_CFG_1, but the
         * 83xx controller has an extended REFREC field of three bits.
         * The controller automatically adds 8 clocks to this value,
         * so preadjust it down 8 first before splitting it up.
         */
        trfc_low = (trfc_clk - 8) & 0xf;
        trfc_high = ((trfc_clk - 8) >> 4) & 0x3;

        ddr->timing_cfg_1 =
            (((picos_to_clk(spd.trp * 250) & 0x07) << 28 ) |    /* PRETOACT */
             ((picos_to_clk(spd.tras * 1000) & 0x0f ) << 24 ) | /* ACTTOPRE */
             (trcd_clk << 20 ) |                                /* ACTTORW */
             (caslat_ctrl << 16 ) |                             /* CASLAT */
             (trfc_low << 12 ) |                                /* REFEC */
             ((twr_clk & 0x07) << 8) |                          /* WRRREC */
             ((picos_to_clk(spd.trrd * 250) & 0x07) << 4) |     /* ACTTOACT */
             ((twtr_clk & 0x07) << 0)                           /* WRTORD */
            );

        /*
         * Additive Latency
         * For DDR I, 0.
         * For DDR II, with ODT enabled, use "a value" less than ACTTORW,
         * which comes from Trcd, and also note that:
         *      add_lat + caslat must be >= 4
         */
        add_lat = 0;
        if (spd.mem_type == SPD_MEMTYPE_DDR2
            && (odt_wr_cfg || odt_rd_cfg)
            && (caslat < 4)) {
                add_lat = trcd_clk - 1;
                if ((add_lat + caslat) < 4) {
                        add_lat = 0;
                }
        }

        /*
         * Write Data Delay
         * Historically 0x2 == 4/8 clock delay.
         * Empirically, 0x3 == 6/8 clock delay is suggested for DDR I 266.
         */
        wr_data_delay = 2;

        /*
         * Write Latency
         * Read to Precharge
         * Minimum CKE Pulse Width.
         * Four Activate Window
         */
        if (spd.mem_type == SPD_MEMTYPE_DDR) {
                /*
                 * This is a lie.  It should really be 1, but if it is
                 * set to 1, bits overlap into the old controller's
                 * otherwise unused ACSM field.  If we leave it 0, then
                 * the HW will magically treat it as 1 for DDR 1.  Oh Yea.
                 */
                wr_lat = 0;

                trtp_clk = 2;           /* By the book. */
                cke_min_clk = 1;        /* By the book. */
                four_act = 1;           /* By the book. */

        } else {
                wr_lat = caslat - 1;

                /* Convert SPD value from quarter nanos to picos. */
                trtp_clk = picos_to_clk(spd.trtp * 250);

                cke_min_clk = 3;        /* By the book. */
                four_act = picos_to_clk(37500); /* By the book. 1k pages? */
        }

        /*
         * Empirically set ~MCAS-to-preamble override for DDR 2.
         * Your milage will vary.
         */
        cpo = 0;
        if (spd.mem_type == SPD_MEMTYPE_DDR2) {
                if (effective_data_rate == 266 || effective_data_rate == 333) {
                        cpo = 0x7;              /* READ_LAT + 5/4 */
                } else if (effective_data_rate == 400) {
                        cpo = 0x9;              /* READ_LAT + 7/4 */
                } else {
                        /* Automatic calibration */
                        cpo = 0x1f;
                }
        }

        ddr->timing_cfg_2 = (0
                | ((add_lat & 0x7) << 28)               /* ADD_LAT */
                | ((cpo & 0x1f) << 23)                  /* CPO */
                | ((wr_lat & 0x7) << 19)                /* WR_LAT */
                | ((trtp_clk & 0x7) << 13)              /* RD_TO_PRE */
                | ((wr_data_delay & 0x7) << 10)         /* WR_DATA_DELAY */
                | ((cke_min_clk & 0x7) << 6)            /* CKE_PLS */
                | ((four_act & 0x1f) << 0)              /* FOUR_ACT */
                );

        debug("DDR:timing_cfg_1=0x%08x\n", ddr->timing_cfg_1);
        debug("DDR:timing_cfg_2=0x%08x\n", ddr->timing_cfg_2);

        /* Check DIMM data bus width */
        if (spd.dataw_lsb == 0x20) {
                if (spd.mem_type == SPD_MEMTYPE_DDR)
                        burstlen = 0x03; /* 32 bit data bus, burst len is 8 */
                else
                        burstlen = 0x02; /* 32 bit data bus, burst len is 4 */
                debug("\n   DDR DIMM: data bus width is 32 bit");
        } else {
                burstlen = 0x02; /* Others act as 64 bit bus, burst len is 4 */
                debug("\n   DDR DIMM: data bus width is 64 bit");
        }

        /* Is this an ECC DDR chip? */
        if (spd.config == 0x02)
                debug(" with ECC\n");
        else
                debug(" without ECC\n");

        /* Burst length is always 4 for 64 bit data bus, 8 for 32 bit data bus,
           Burst type is sequential
         */
        if (spd.mem_type == SPD_MEMTYPE_DDR) {
                switch (caslat) {
                case 1:
                        ddr->sdram_mode = 0x50 | burstlen; /* CL=1.5 */
                        break;
                case 2:
                        ddr->sdram_mode = 0x20 | burstlen; /* CL=2.0 */
                        break;
                case 3:
                        ddr->sdram_mode = 0x60 | burstlen; /* CL=2.5 */
                        break;
                case 4:
                        ddr->sdram_mode = 0x30 | burstlen; /* CL=3.0 */
                        break;
                default:
                        printf("DDR:only CL 1.5, 2.0, 2.5, 3.0 is supported\n");
                        return 0;
                }
        } else {
                mode_odt_enable = 0x0;                  /* Default disabled */
                if (odt_wr_cfg || odt_rd_cfg) {
                        /*
                         * Bits 6 and 2 in Extended MRS(1)
                         * Bit 2 == 0x04 == 75 Ohm, with 2 DIMM modules.
                         * Bit 6 == 0x40 == 150 Ohm, with 1 DIMM module.
                         */
                        mode_odt_enable = 0x40;         /* 150 Ohm */
                }

                ddr->sdram_mode =
                        (0
                         | (1 << (16 + 10))             /* DQS Differential disable */
                         | (add_lat << (16 + 3))        /* Additive Latency in EMRS1 */
                         | (mode_odt_enable << 16)      /* ODT Enable in EMRS1 */
                         | ((twr_clk - 1) << 9)         /* Write Recovery Autopre */
                         | (caslat << 4)                /* caslat */
                         | (burstlen << 0)              /* Burst length */
                        );
        }
        debug("DDR:sdram_mode=0x%08x\n", ddr->sdram_mode);

        /*
         * Clear EMRS2 and EMRS3.
         */
        ddr->sdram_mode2 = 0;
        debug("DDR: sdram_mode2 = 0x%08x\n", ddr->sdram_mode2);

        switch (spd.refresh) {
                case 0x00:
                case 0x80:
                        refresh_clk = picos_to_clk(15625000);
                        break;
                case 0x01:
                case 0x81:
                        refresh_clk = picos_to_clk(3900000);
                        break;
                case 0x02:
                case 0x82:
                        refresh_clk = picos_to_clk(7800000);
                        break;
                case 0x03:
                case 0x83:
                        refresh_clk = picos_to_clk(31300000);
                        break;
                case 0x04:
                case 0x84:
                        refresh_clk = picos_to_clk(62500000);
                        break;
                case 0x05:
                case 0x85:
                        refresh_clk = picos_to_clk(125000000);
                        break;
                default:
                        refresh_clk = 0x512;
                        break;
        }

        /*
         * Set BSTOPRE to 0x100 for page mode
         * If auto-charge is used, set BSTOPRE = 0
         */
        ddr->sdram_interval = ((refresh_clk & 0x3fff) << 16) | 0x100;
        debug("DDR:sdram_interval=0x%08x\n", ddr->sdram_interval);

        /*
         * SDRAM Cfg 2
         */
        odt_cfg = 0;
        if (odt_rd_cfg | odt_wr_cfg) {
                odt_cfg = 0x2;          /* ODT to IOs during reads */
        }
        if (spd.mem_type == SPD_MEMTYPE_DDR2) {
                ddr->sdram_cfg2 = (0
                            | (0 << 26) /* True DQS */
                            | (odt_cfg << 21)   /* ODT only read */
                            | (1 << 12) /* 1 refresh at a time */
                            );

                debug("DDR: sdram_cfg2  = 0x%08x\n", ddr->sdram_cfg2);
        }

#ifdef CFG_DDR_SDRAM_CLK_CNTL   /* Optional platform specific value */
        ddr->sdram_clk_cntl = CFG_DDR_SDRAM_CLK_CNTL;
#endif
        debug("DDR:sdram_clk_cntl=0x%08x\n", ddr->sdram_clk_cntl);

        asm("sync;isync");

        udelay(600);

        /*
         * Figure out the settings for the sdram_cfg register. Build up
         * the value in 'sdram_cfg' before writing since the write into
         * the register will actually enable the memory controller, and all
         * settings must be done before enabling.
         *
         * sdram_cfg[0]   = 1 (ddr sdram logic enable)
         * sdram_cfg[1]   = 1 (self-refresh-enable)
         * sdram_cfg[5:7] = (SDRAM type = DDR SDRAM)
         *                      010 DDR 1 SDRAM
         *                      011 DDR 2 SDRAM
         * sdram_cfg[12] = 0 (32_BE =0 , 64 bit bus mode)
         * sdram_cfg[13] = 0 (8_BE =0, 4-beat bursts)
         */
        if (spd.mem_type == SPD_MEMTYPE_DDR)
                sdram_type = SDRAM_CFG_SDRAM_TYPE_DDR1;
        else
                sdram_type = SDRAM_CFG_SDRAM_TYPE_DDR1;

        sdram_cfg = (0
                     | SDRAM_CFG_MEM_EN         /* DDR enable */
                     | SDRAM_CFG_SREN           /* Self refresh */
                     | sdram_type               /* SDRAM type */
                     );

        /* sdram_cfg[3] = RD_EN - registered DIMM enable */
        if (spd.mod_attr & 0x02)
                sdram_cfg |= SDRAM_CFG_RD_EN;

        /* The DIMM is 32bit width */
        if (spd.dataw_lsb == 0x20) {
                if (spd.mem_type == SPD_MEMTYPE_DDR)
                        sdram_cfg |= SDRAM_CFG_32_BE | SDRAM_CFG_8_BE;
                if (spd.mem_type == SPD_MEMTYPE_DDR2)
                        sdram_cfg |= SDRAM_CFG_32_BE;
        }

        ddrc_ecc_enable = 0;

#if defined(CONFIG_DDR_ECC)
        /* Enable ECC with sdram_cfg[2] */
        if (spd.config == 0x02) {
                sdram_cfg |= 0x20000000;
                ddrc_ecc_enable = 1;
                /* disable error detection */
                ddr->err_disable = ~ECC_ERROR_ENABLE;
                /* set single bit error threshold to maximum value,
                 * reset counter to zero */
                ddr->err_sbe = (255 << ECC_ERROR_MAN_SBET_SHIFT) |
                                (0 << ECC_ERROR_MAN_SBEC_SHIFT);
        }

        debug("DDR:err_disable=0x%08x\n", ddr->err_disable);
        debug("DDR:err_sbe=0x%08x\n", ddr->err_sbe);
#endif
        debug("   DDRC ECC mode: %s\n", ddrc_ecc_enable ? "ON":"OFF");

#if defined(CONFIG_DDR_2T_TIMING)
        /*
         * Enable 2T timing by setting sdram_cfg[16].
         */
        sdram_cfg |= SDRAM_CFG_2T_EN;
#endif
        /* Enable controller, and GO! */
        ddr->sdram_cfg = sdram_cfg;
        asm("sync;isync");
        udelay(500);

        debug("DDR:sdram_cfg=0x%08x\n", ddr->sdram_cfg);
        return memsize; /*in MBytes*/
}
#endif /* CONFIG_SPD_EEPROM */

#if defined(CONFIG_DDR_ECC) && !defined(CONFIG_ECC_INIT_VIA_DDRC)
/*
 * Use timebase counter, get_timer() is not availabe
 * at this point of initialization yet.
 */
static __inline__ unsigned long get_tbms (void)
{
        unsigned long tbl;
        unsigned long tbu1, tbu2;
        unsigned long ms;
        unsigned long long tmp;

        ulong tbclk = get_tbclk();

        /* get the timebase ticks */
        do {
                asm volatile ("mftbu %0":"=r" (tbu1):);
                asm volatile ("mftb %0":"=r" (tbl):);
                asm volatile ("mftbu %0":"=r" (tbu2):);
        } while (tbu1 != tbu2);

        /* convert ticks to ms */
        tmp = (unsigned long long)(tbu1);
        tmp = (tmp << 32);
        tmp += (unsigned long long)(tbl);
        ms = tmp/(tbclk/1000);

        return ms;
}

/*
 * Initialize all of memory for ECC, then enable errors.
 */
/* #define CONFIG_DDR_ECC_INIT_VIA_DMA */
void ddr_enable_ecc(unsigned int dram_size)
{
        volatile immap_t *immap = (immap_t *)CFG_IMMR;
        volatile ddr83xx_t *ddr= &immap->ddr;
        unsigned long t_start, t_end;
        register u64 *p;
        register uint size;
        unsigned int pattern[2];
#if defined(CONFIG_DDR_ECC_INIT_VIA_DMA)
        uint i;
#endif
        icache_enable();
        t_start = get_tbms();
        pattern[0] = 0xdeadbeef;
        pattern[1] = 0xdeadbeef;

#if !defined(CONFIG_DDR_ECC_INIT_VIA_DMA)
        debug("ddr init: CPU FP write method\n");
        size = dram_size;
        for (p = 0; p < (u64*)(size); p++) {
                ppcDWstore((u32*)p, pattern);
        }
        __asm__ __volatile__ ("sync");
#else
        debug("ddr init: DMA method\n");
        size = 0x2000;
        for (p = 0; p < (u64*)(size); p++) {
                ppcDWstore((u32*)p, pattern);
        }
        __asm__ __volatile__ ("sync");

        /* Initialise DMA for direct transfer */
        dma_init();
        /* Start DMA to transfer */
        dma_xfer((uint *)0x2000, 0x2000, (uint *)0); /* 8K */
        dma_xfer((uint *)0x4000, 0x4000, (uint *)0); /* 16K */
        dma_xfer((uint *)0x8000, 0x8000, (uint *)0); /* 32K */
        dma_xfer((uint *)0x10000, 0x10000, (uint *)0); /* 64K */
        dma_xfer((uint *)0x20000, 0x20000, (uint *)0); /* 128K */
        dma_xfer((uint *)0x40000, 0x40000, (uint *)0); /* 256K */
        dma_xfer((uint *)0x80000, 0x80000, (uint *)0); /* 512K */
        dma_xfer((uint *)0x100000, 0x100000, (uint *)0); /* 1M */
        dma_xfer((uint *)0x200000, 0x200000, (uint *)0); /* 2M */
        dma_xfer((uint *)0x400000, 0x400000, (uint *)0); /* 4M */

        for (i = 1; i < dram_size / 0x800000; i++) {
                dma_xfer((uint *)(0x800000*i), 0x800000, (uint *)0);
        }
#endif

        t_end = get_tbms();
        icache_disable();

        debug("\nREADY!!\n");
        debug("ddr init duration: %ld ms\n", t_end - t_start);

        /* Clear All ECC Errors */
        if ((ddr->err_detect & ECC_ERROR_DETECT_MME) == ECC_ERROR_DETECT_MME)
                ddr->err_detect |= ECC_ERROR_DETECT_MME;
        if ((ddr->err_detect & ECC_ERROR_DETECT_MBE) == ECC_ERROR_DETECT_MBE)
                ddr->err_detect |= ECC_ERROR_DETECT_MBE;
        if ((ddr->err_detect & ECC_ERROR_DETECT_SBE) == ECC_ERROR_DETECT_SBE)
                ddr->err_detect |= ECC_ERROR_DETECT_SBE;
        if ((ddr->err_detect & ECC_ERROR_DETECT_MSE) == ECC_ERROR_DETECT_MSE)
                ddr->err_detect |= ECC_ERROR_DETECT_MSE;

        /* Disable ECC-Interrupts */
        ddr->err_int_en &= ECC_ERR_INT_DISABLE;

        /* Enable errors for ECC */
        ddr->err_disable &= ECC_ERROR_ENABLE;

        __asm__ __volatile__ ("sync");
        __asm__ __volatile__ ("isync");
}
#endif  /* CONFIG_DDR_ECC */