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  •  * Copyright 2008-2010 Freescale Semiconductor, Inc.
    
     * 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.
    
     */
    
    /*
     * Generic driver for Freescale DDR/DDR2/DDR3 memory controller.
     * Based on code from spd_sdram.c
     * Author: James Yang [at freescale.com]
     */
    
    #include <common.h>
    #include <asm/fsl_ddr_sdram.h>
    
    #include "ddr.h"
    
    extern unsigned int picos_to_mclk(unsigned int picos);
    /*
     * Determine Rtt value.
     *
     * This should likely be either board or controller specific.
     *
    
     * Rtt(nominal) - DDR2:
    
     *	0 = Rtt disabled
     *	1 = 75 ohm
     *	2 = 150 ohm
     *	3 = 50 ohm
    
     * Rtt(nominal) - DDR3:
     *	0 = Rtt disabled
     *	1 = 60 ohm
     *	2 = 120 ohm
     *	3 = 40 ohm
     *	4 = 20 ohm
     *	5 = 30 ohm
    
     *
     * FIXME: Apparently 8641 needs a value of 2
     * FIXME: Old code seys if 667 MHz or higher, use 3 on 8572
     *
     * FIXME: There was some effort down this line earlier:
     *
     *	unsigned int i;
     *	for (i = 0; i < CONFIG_CHIP_SELECTS_PER_CTRL/2; i++) {
     *		if (popts->dimmslot[i].num_valid_cs
     *		    && (popts->cs_local_opts[2*i].odt_rd_cfg
     *			|| popts->cs_local_opts[2*i].odt_wr_cfg)) {
     *			rtt = 2;
     *			break;
     *		}
     *	}
     */
    static inline int fsl_ddr_get_rtt(void)
    {
    	int rtt;
    
    #if defined(CONFIG_FSL_DDR1)
    	rtt = 0;
    #elif defined(CONFIG_FSL_DDR2)
    	rtt = 3;
    #else
    
    /*
     * compute the CAS write latency according to DDR3 spec
     * CWL = 5 if tCK >= 2.5ns
     *       6 if 2.5ns > tCK >= 1.875ns
     *       7 if 1.875ns > tCK >= 1.5ns
     *       8 if 1.5ns > tCK >= 1.25ns
     */
    static inline unsigned int compute_cas_write_latency(void)
    {
    	unsigned int cwl;
    	const unsigned int mclk_ps = get_memory_clk_period_ps();
    
    	if (mclk_ps >= 2500)
    		cwl = 5;
    	else if (mclk_ps >= 1875)
    		cwl = 6;
    	else if (mclk_ps >= 1500)
    		cwl = 7;
    	else if (mclk_ps >= 1250)
    		cwl = 8;
    	else
    		cwl = 8;
    	return cwl;
    }
    
    
    /* Chip Select Configuration (CSn_CONFIG) */
    
    static void set_csn_config(int dimm_number, int i, fsl_ddr_cfg_regs_t *ddr,
    
    			       const memctl_options_t *popts,
    			       const dimm_params_t *dimm_params)
    {
    	unsigned int cs_n_en = 0; /* Chip Select enable */
    	unsigned int intlv_en = 0; /* Memory controller interleave enable */
    	unsigned int intlv_ctl = 0; /* Interleaving control */
    	unsigned int ap_n_en = 0; /* Chip select n auto-precharge enable */
    	unsigned int odt_rd_cfg = 0; /* ODT for reads configuration */
    	unsigned int odt_wr_cfg = 0; /* ODT for writes configuration */
    	unsigned int ba_bits_cs_n = 0; /* Num of bank bits for SDRAM on CSn */
    	unsigned int row_bits_cs_n = 0; /* Num of row bits for SDRAM on CSn */
    	unsigned int col_bits_cs_n = 0; /* Num of ocl bits for SDRAM on CSn */
    
    	int go_config = 0;
    
    
    	/* Compute CS_CONFIG only for existing ranks of each DIMM.  */
    
    	switch (i) {
    	case 0:
    		if (dimm_params[dimm_number].n_ranks > 0) {
    			go_config = 1;
    
    			/* These fields only available in CS0_CONFIG */
    			intlv_en = popts->memctl_interleaving;
    			intlv_ctl = popts->memctl_interleaving_mode;
    		}
    
    		break;
    	case 1:
    		if ((dimm_number == 0 && dimm_params[0].n_ranks > 1) || \
    		    (dimm_number == 1 && dimm_params[1].n_ranks > 0))
    			go_config = 1;
    		break;
    	case 2:
    		if ((dimm_number == 0 && dimm_params[0].n_ranks > 2) || \
    		   (dimm_number > 1 && dimm_params[dimm_number].n_ranks > 0))
    			go_config = 1;
    		break;
    	case 3:
    		if ((dimm_number == 0 && dimm_params[0].n_ranks > 3) || \
    		    (dimm_number == 1 && dimm_params[1].n_ranks > 1) || \
    		    (dimm_number == 3 && dimm_params[3].n_ranks > 0))
    			go_config = 1;
    		break;
    	default:
    		break;
    	}
    	if (go_config) {
    		unsigned int n_banks_per_sdram_device;
    		cs_n_en = 1;
    
    		ap_n_en = popts->cs_local_opts[i].auto_precharge;
    		odt_rd_cfg = popts->cs_local_opts[i].odt_rd_cfg;
    		odt_wr_cfg = popts->cs_local_opts[i].odt_wr_cfg;
    		n_banks_per_sdram_device
    
    			= dimm_params[dimm_number].n_banks_per_sdram_device;
    
    		ba_bits_cs_n = __ilog2(n_banks_per_sdram_device) - 2;
    
    		row_bits_cs_n = dimm_params[dimm_number].n_row_addr - 12;
    		col_bits_cs_n = dimm_params[dimm_number].n_col_addr - 8;
    
    	}
    	ddr->cs[i].config = (0
    		| ((cs_n_en & 0x1) << 31)
    		| ((intlv_en & 0x3) << 29)
    
    		| ((intlv_ctl & 0xf) << 24)
    
    		| ((ap_n_en & 0x1) << 23)
    
    		/* XXX: some implementation only have 1 bit starting at left */
    		| ((odt_rd_cfg & 0x7) << 20)
    
    		/* XXX: Some implementation only have 1 bit starting at left */
    		| ((odt_wr_cfg & 0x7) << 16)
    
    		| ((ba_bits_cs_n & 0x3) << 14)
    		| ((row_bits_cs_n & 0x7) << 8)
    		| ((col_bits_cs_n & 0x7) << 0)
    		);
    
    	debug("FSLDDR: cs[%d]_config = 0x%08x\n", i,ddr->cs[i].config);
    
    }
    
    /* Chip Select Configuration 2 (CSn_CONFIG_2) */
    /* FIXME: 8572 */
    static void set_csn_config_2(int i, fsl_ddr_cfg_regs_t *ddr)
    {
    	unsigned int pasr_cfg = 0;	/* Partial array self refresh config */
    
    	ddr->cs[i].config_2 = ((pasr_cfg & 7) << 24);
    
    	debug("FSLDDR: cs[%d]_config_2 = 0x%08x\n", i, ddr->cs[i].config_2);
    
    }
    
    /* -3E = 667 CL5, -25 = CL6 800, -25E = CL5 800 */
    
    
    #if !defined(CONFIG_FSL_DDR1)
    
    /*
     * DDR SDRAM Timing Configuration 0 (TIMING_CFG_0)
     *
     * Avoid writing for DDR I.  The new PQ38 DDR controller
     * dreams up non-zero default values to be backwards compatible.
     */
    static void set_timing_cfg_0(fsl_ddr_cfg_regs_t *ddr)
    {
    	unsigned char trwt_mclk = 0;   /* Read-to-write turnaround */
    	unsigned char twrt_mclk = 0;   /* Write-to-read turnaround */
    	/* 7.5 ns on -3E; 0 means WL - CL + BL/2 + 1 */
    	unsigned char trrt_mclk = 0;   /* Read-to-read turnaround */
    	unsigned char twwt_mclk = 0;   /* Write-to-write turnaround */
    
    	/* Active powerdown exit timing (tXARD and tXARDS). */
    	unsigned char act_pd_exit_mclk;
    	/* Precharge powerdown exit timing (tXP). */
    	unsigned char pre_pd_exit_mclk;
    	/* Precharge powerdown exit timing (tAXPD). */
    	unsigned char taxpd_mclk;
    	/* Mode register set cycle time (tMRD). */
    	unsigned char tmrd_mclk;
    
    
    #if defined(CONFIG_FSL_DDR3)
    	/*
    	 * (tXARD and tXARDS). Empirical?
    	 * The DDR3 spec has not tXARD,
    	 * we use the tXP instead of it.
    	 * tXP=max(3nCK, 7.5ns) for DDR3.
    	 * spec has not the tAXPD, we use
    	 * tAXPD=8, need design to confirm.
    	 */
    
    	int tXP = max((get_memory_clk_period_ps() * 3), 7500); /* unit=ps */
    	act_pd_exit_mclk = picos_to_mclk(tXP);
    	/* Mode register MR0[A12] is '1' - fast exit */
    	pre_pd_exit_mclk = act_pd_exit_mclk;
    
    	tmrd_mclk = 4;
    
    	/* set the turnaround time */
    	trwt_mclk = 1;
    
    #else /* CONFIG_FSL_DDR2 */
    	/*
    	 * (tXARD and tXARDS). Empirical?
    	 * tXARD = 2 for DDR2
    	 * tXP=2
    	 * tAXPD=8
    	 */
    	act_pd_exit_mclk = 2;
    	pre_pd_exit_mclk = 2;
    	taxpd_mclk = 8;
    
    
    	ddr->timing_cfg_0 = (0
    		| ((trwt_mclk & 0x3) << 30)	/* RWT */
    		| ((twrt_mclk & 0x3) << 28)	/* WRT */
    		| ((trrt_mclk & 0x3) << 26)	/* RRT */
    		| ((twwt_mclk & 0x3) << 24)	/* WWT */
    		| ((act_pd_exit_mclk & 0x7) << 20)  /* ACT_PD_EXIT */
    
    		| ((pre_pd_exit_mclk & 0xF) << 16)  /* PRE_PD_EXIT */
    
    		| ((taxpd_mclk & 0xf) << 8)	/* ODT_PD_EXIT */
    		| ((tmrd_mclk & 0xf) << 0)	/* MRS_CYC */
    		);
    	debug("FSLDDR: timing_cfg_0 = 0x%08x\n", ddr->timing_cfg_0);
    }
    #endif	/* defined(CONFIG_FSL_DDR2) */
    
    /* DDR SDRAM Timing Configuration 3 (TIMING_CFG_3) */
    static void set_timing_cfg_3(fsl_ddr_cfg_regs_t *ddr,
    
    			       const common_timing_params_t *common_dimm,
    			       unsigned int cas_latency)
    
    {
    	/* Extended Activate to precharge interval (tRAS) */
    	unsigned int ext_acttopre = 0;
    	unsigned int ext_refrec; /* Extended refresh recovery time (tRFC) */
    	unsigned int ext_caslat = 0; /* Extended MCAS latency from READ cmd */
    	unsigned int cntl_adj = 0; /* Control Adjust */
    
    
    	/* If the tRAS > 19 MCLK, we use the ext mode */
    	if (picos_to_mclk(common_dimm->tRAS_ps) > 0x13)
    		ext_acttopre = 1;
    
    
    	ext_refrec = (picos_to_mclk(common_dimm->tRFC_ps) - 8) >> 4;
    
    
    	/* If the CAS latency more than 8, use the ext mode */
    	if (cas_latency > 8)
    		ext_caslat = 1;
    
    
    	ddr->timing_cfg_3 = (0
    		| ((ext_acttopre & 0x1) << 24)
    
    		| ((ext_refrec & 0xF) << 16)
    
    		| ((ext_caslat & 0x1) << 12)
    		| ((cntl_adj & 0x7) << 0)
    		);
    
    	debug("FSLDDR: timing_cfg_3 = 0x%08x\n", ddr->timing_cfg_3);
    
    }
    
    /* DDR SDRAM Timing Configuration 1 (TIMING_CFG_1) */
    static void set_timing_cfg_1(fsl_ddr_cfg_regs_t *ddr,
    
    			       const memctl_options_t *popts,
    
    			       const common_timing_params_t *common_dimm,
    			       unsigned int cas_latency)
    {
    	/* Precharge-to-activate interval (tRP) */
    	unsigned char pretoact_mclk;
    	/* Activate to precharge interval (tRAS) */
    	unsigned char acttopre_mclk;
    	/*  Activate to read/write interval (tRCD) */
    	unsigned char acttorw_mclk;
    	/* CASLAT */
    	unsigned char caslat_ctrl;
    	/*  Refresh recovery time (tRFC) ; trfc_low */
    	unsigned char refrec_ctrl;
    	/* Last data to precharge minimum interval (tWR) */
    	unsigned char wrrec_mclk;
    	/* Activate-to-activate interval (tRRD) */
    	unsigned char acttoact_mclk;
    	/* Last write data pair to read command issue interval (tWTR) */
    	unsigned char wrtord_mclk;
    
    	pretoact_mclk = picos_to_mclk(common_dimm->tRP_ps);
    	acttopre_mclk = picos_to_mclk(common_dimm->tRAS_ps);
    	acttorw_mclk = picos_to_mclk(common_dimm->tRCD_ps);
    
    	/*
    	 * Translate CAS Latency 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             4       0111
    	 *      4.5                     1000
    	 *      5.0             5       1001
    	 */
    #if defined(CONFIG_FSL_DDR1)
    	caslat_ctrl = (cas_latency + 1) & 0x07;
    #elif defined(CONFIG_FSL_DDR2)
    	caslat_ctrl = 2 * cas_latency - 1;
    #else
    
    	/*
    	 * if the CAS latency more than 8 cycle,
    	 * we need set extend bit for it at
    	 * TIMING_CFG_3[EXT_CASLAT]
    	 */
    	if (cas_latency > 8)
    		cas_latency -= 8;
    	caslat_ctrl = 2 * cas_latency - 1;
    
    #endif
    
    	refrec_ctrl = picos_to_mclk(common_dimm->tRFC_ps) - 8;
    	wrrec_mclk = picos_to_mclk(common_dimm->tWR_ps);
    
    	if (popts->OTF_burst_chop_en)
    		wrrec_mclk += 2;
    
    
    	acttoact_mclk = picos_to_mclk(common_dimm->tRRD_ps);
    
    	/*
    	 * JEDEC has min requirement for tRRD
    	 */
    #if defined(CONFIG_FSL_DDR3)
    	if (acttoact_mclk < 4)
    		acttoact_mclk = 4;
    #endif
    
    	wrtord_mclk = picos_to_mclk(common_dimm->tWTR_ps);
    
    	/*
    	 * JEDEC has some min requirements for tWTR
    	 */
    #if defined(CONFIG_FSL_DDR2)
    	if (wrtord_mclk < 2)
    		wrtord_mclk = 2;
    #elif defined(CONFIG_FSL_DDR3)
    	if (wrtord_mclk < 4)
    		wrtord_mclk = 4;
    #endif
    	if (popts->OTF_burst_chop_en)
    		wrtord_mclk += 2;
    
    		| ((pretoact_mclk & 0x0F) << 28)
    
    		| ((acttopre_mclk & 0x0F) << 24)
    
    		| ((acttorw_mclk & 0xF) << 20)
    
    		| ((caslat_ctrl & 0xF) << 16)
    		| ((refrec_ctrl & 0xF) << 12)
    
    		| ((wrrec_mclk & 0x0F) << 8)
    
    		| ((acttoact_mclk & 0x07) << 4)
    		| ((wrtord_mclk & 0x07) << 0)
    		);
    
    	debug("FSLDDR: timing_cfg_1 = 0x%08x\n", ddr->timing_cfg_1);
    
    }
    
    /* DDR SDRAM Timing Configuration 2 (TIMING_CFG_2) */
    static void set_timing_cfg_2(fsl_ddr_cfg_regs_t *ddr,
    			       const memctl_options_t *popts,
    			       const common_timing_params_t *common_dimm,
    			       unsigned int cas_latency,
    			       unsigned int additive_latency)
    {
    	/* Additive latency */
    	unsigned char add_lat_mclk;
    	/* CAS-to-preamble override */
    	unsigned short cpo;
    	/* Write latency */
    	unsigned char wr_lat;
    	/*  Read to precharge (tRTP) */
    	unsigned char rd_to_pre;
    	/* Write command to write data strobe timing adjustment */
    	unsigned char wr_data_delay;
    	/* Minimum CKE pulse width (tCKE) */
    	unsigned char cke_pls;
    	/* Window for four activates (tFAW) */
    	unsigned short four_act;
    
    	/* FIXME add check that this must be less than acttorw_mclk */
    	add_lat_mclk = additive_latency;
    	cpo = popts->cpo_override;
    
    #if defined(CONFIG_FSL_DDR1)
    	/*
    	 * 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;
    #elif defined(CONFIG_FSL_DDR2)
    
    	wr_lat = cas_latency - 1;
    
    	wr_lat = compute_cas_write_latency();
    
    #endif
    
    	rd_to_pre = picos_to_mclk(common_dimm->tRTP_ps);
    
    	/*
    	 * JEDEC has some min requirements for tRTP
    	 */
    
    #if defined(CONFIG_FSL_DDR2)
    
    	if (rd_to_pre  < 2)
    		rd_to_pre  = 2;
    #elif defined(CONFIG_FSL_DDR3)
    	if (rd_to_pre < 4)
    		rd_to_pre = 4;
    
    	if (additive_latency)
    		rd_to_pre += additive_latency;
    	if (popts->OTF_burst_chop_en)
    		rd_to_pre += 2; /* according to UM */
    
    
    	wr_data_delay = popts->write_data_delay;
    	cke_pls = picos_to_mclk(popts->tCKE_clock_pulse_width_ps);
    	four_act = picos_to_mclk(popts->tFAW_window_four_activates_ps);
    
    	ddr->timing_cfg_2 = (0
    
    		| ((add_lat_mclk & 0xf) << 28)
    
    		| ((wr_lat & 0xf) << 19)
    
    		| ((rd_to_pre & RD_TO_PRE_MASK) << RD_TO_PRE_SHIFT)
    		| ((wr_data_delay & WR_DATA_DELAY_MASK) << WR_DATA_DELAY_SHIFT)
    
    		| ((cke_pls & 0x7) << 6)
    
    		| ((four_act & 0x3f) << 0)
    
    	debug("FSLDDR: timing_cfg_2 = 0x%08x\n", ddr->timing_cfg_2);
    
    }
    
    /* DDR SDRAM control configuration (DDR_SDRAM_CFG) */
    static void set_ddr_sdram_cfg(fsl_ddr_cfg_regs_t *ddr,
    			       const memctl_options_t *popts,
    			       const common_timing_params_t *common_dimm)
    {
    	unsigned int mem_en;		/* DDR SDRAM interface logic enable */
    	unsigned int sren;		/* Self refresh enable (during sleep) */
    	unsigned int ecc_en;		/* ECC enable. */
    	unsigned int rd_en;		/* Registered DIMM enable */
    	unsigned int sdram_type;	/* Type of SDRAM */
    	unsigned int dyn_pwr;		/* Dynamic power management mode */
    	unsigned int dbw;		/* DRAM dta bus width */
    
    	unsigned int eight_be = 0;	/* 8-beat burst enable, DDR2 is zero */
    
    	unsigned int ncap = 0;		/* Non-concurrent auto-precharge */
    	unsigned int threeT_en;		/* Enable 3T timing */
    	unsigned int twoT_en;		/* Enable 2T timing */
    	unsigned int ba_intlv_ctl;	/* Bank (CS) interleaving control */
    	unsigned int x32_en = 0;	/* x32 enable */
    	unsigned int pchb8 = 0;		/* precharge bit 8 enable */
    	unsigned int hse;		/* Global half strength override */
    	unsigned int mem_halt = 0;	/* memory controller halt */
    	unsigned int bi = 0;		/* Bypass initialization */
    
    	mem_en = 1;
    	sren = popts->self_refresh_in_sleep;
    	if (common_dimm->all_DIMMs_ECC_capable) {
    		/* Allow setting of ECC only if all DIMMs are ECC. */
    		ecc_en = popts->ECC_mode;
    	} else {
    		ecc_en = 0;
    	}
    
    	rd_en = (common_dimm->all_DIMMs_registered
    		 && !common_dimm->all_DIMMs_unbuffered);
    
    	sdram_type = CONFIG_FSL_SDRAM_TYPE;
    
    	dyn_pwr = popts->dynamic_power;
    	dbw = popts->data_bus_width;
    
    	/* 8-beat burst enable DDR-III case
    	 * we must clear it when use the on-the-fly mode,
    	 * must set it when use the 32-bits bus mode.
    	 */
    	if (sdram_type == SDRAM_TYPE_DDR3) {
    		if (popts->burst_length == DDR_BL8)
    			eight_be = 1;
    		if (popts->burst_length == DDR_OTF)
    			eight_be = 0;
    		if (dbw == 0x1)
    			eight_be = 1;
    	}
    
    
    	threeT_en = popts->threeT_en;
    	twoT_en = popts->twoT_en;
    	ba_intlv_ctl = popts->ba_intlv_ctl;
    	hse = popts->half_strength_driver_enable;
    
    	ddr->ddr_sdram_cfg = (0
    			| ((mem_en & 0x1) << 31)
    			| ((sren & 0x1) << 30)
    			| ((ecc_en & 0x1) << 29)
    			| ((rd_en & 0x1) << 28)
    			| ((sdram_type & 0x7) << 24)
    			| ((dyn_pwr & 0x1) << 21)
    			| ((dbw & 0x3) << 19)
    			| ((eight_be & 0x1) << 18)
    			| ((ncap & 0x1) << 17)
    			| ((threeT_en & 0x1) << 16)
    			| ((twoT_en & 0x1) << 15)
    			| ((ba_intlv_ctl & 0x7F) << 8)
    			| ((x32_en & 0x1) << 5)
    			| ((pchb8 & 0x1) << 4)
    			| ((hse & 0x1) << 3)
    			| ((mem_halt & 0x1) << 1)
    			| ((bi & 0x1) << 0)
    			);
    
    	debug("FSLDDR: ddr_sdram_cfg = 0x%08x\n", ddr->ddr_sdram_cfg);
    
    }
    
    /* DDR SDRAM control configuration 2 (DDR_SDRAM_CFG_2) */
    static void set_ddr_sdram_cfg_2(fsl_ddr_cfg_regs_t *ddr,
    			       const memctl_options_t *popts)
    {
    	unsigned int frc_sr = 0;	/* Force self refresh */
    	unsigned int sr_ie = 0;		/* Self-refresh interrupt enable */
    	unsigned int dll_rst_dis;	/* DLL reset disable */
    	unsigned int dqs_cfg;		/* DQS configuration */
    	unsigned int odt_cfg;		/* ODT configuration */
    	unsigned int num_pr;		/* Number of posted refreshes */
    	unsigned int obc_cfg;		/* On-The-Fly Burst Chop Cfg */
    	unsigned int ap_en;		/* Address Parity Enable */
    	unsigned int d_init;		/* DRAM data initialization */
    	unsigned int rcw_en = 0;	/* Register Control Word Enable */
    	unsigned int md_en = 0;		/* Mirrored DIMM Enable */
    
    	unsigned int qd_en = 0;		/* quad-rank DIMM Enable */
    
    
    	dll_rst_dis = 1;	/* Make this configurable */
    	dqs_cfg = popts->DQS_config;
    	if (popts->cs_local_opts[0].odt_rd_cfg
    	    || popts->cs_local_opts[0].odt_wr_cfg) {
    		/* FIXME */
    		odt_cfg = 2;
    	} else {
    		odt_cfg = 0;
    	}
    
    	num_pr = 1;	/* Make this configurable */
    
    	/*
    	 * 8572 manual says
    	 *     {TIMING_CFG_1[PRETOACT]
    	 *      + [DDR_SDRAM_CFG_2[NUM_PR]
    	 *        * ({EXT_REFREC || REFREC} + 8 + 2)]}
    	 *      << DDR_SDRAM_INTERVAL[REFINT]
    	 */
    
    #if defined(CONFIG_FSL_DDR3)
    	obc_cfg = popts->OTF_burst_chop_en;
    #else
    	obc_cfg = 0;
    #endif
    
    
    	ap_en = 0;	/* Make this configurable? */
    
    #if defined(CONFIG_ECC_INIT_VIA_DDRCONTROLLER)
    	/* Use the DDR controller to auto initialize memory. */
    	d_init = 1;
    	ddr->ddr_data_init = CONFIG_MEM_INIT_VALUE;
    	debug("DDR: ddr_data_init = 0x%08x\n", ddr->ddr_data_init);
    #else
    	/* Memory will be initialized via DMA, or not at all. */
    	d_init = 0;
    #endif
    
    
    #if defined(CONFIG_FSL_DDR3)
    	md_en = popts->mirrored_dimm;
    #endif
    
    	qd_en = popts->quad_rank_present ? 1 : 0;
    
    	ddr->ddr_sdram_cfg_2 = (0
    		| ((frc_sr & 0x1) << 31)
    		| ((sr_ie & 0x1) << 30)
    		| ((dll_rst_dis & 0x1) << 29)
    		| ((dqs_cfg & 0x3) << 26)
    		| ((odt_cfg & 0x3) << 21)
    		| ((num_pr & 0xf) << 12)
    
    		| (qd_en << 9)
    
    		| ((obc_cfg & 0x1) << 6)
    		| ((ap_en & 0x1) << 5)
    		| ((d_init & 0x1) << 4)
    		| ((rcw_en & 0x1) << 2)
    		| ((md_en & 0x1) << 0)
    		);
    
    	debug("FSLDDR: ddr_sdram_cfg_2 = 0x%08x\n", ddr->ddr_sdram_cfg_2);
    
    }
    
    /* DDR SDRAM Mode configuration 2 (DDR_SDRAM_MODE_2) */
    
    static void set_ddr_sdram_mode_2(fsl_ddr_cfg_regs_t *ddr,
    				const memctl_options_t *popts)
    
    {
    	unsigned short esdmode2 = 0;	/* Extended SDRAM mode 2 */
    	unsigned short esdmode3 = 0;	/* Extended SDRAM mode 3 */
    
    
    #if defined(CONFIG_FSL_DDR3)
    
    	unsigned int rtt_wr = 0;	/* Rtt_WR - dynamic ODT off */
    
    	unsigned int srt = 0;	/* self-refresh temerature, normal range */
    	unsigned int asr = 0;	/* auto self-refresh disable */
    	unsigned int cwl = compute_cas_write_latency() - 5;
    	unsigned int pasr = 0;	/* partial array self refresh disable */
    
    
    	if (popts->rtt_override)
    		rtt_wr = popts->rtt_wr_override_value;
    
    
    	esdmode2 = (0
    		| ((rtt_wr & 0x3) << 9)
    		| ((srt & 0x1) << 7)
    		| ((asr & 0x1) << 6)
    		| ((cwl & 0x7) << 3)
    		| ((pasr & 0x7) << 0));
    #endif
    
    	ddr->ddr_sdram_mode_2 = (0
    				 | ((esdmode2 & 0xFFFF) << 16)
    				 | ((esdmode3 & 0xFFFF) << 0)
    				 );
    
    	debug("FSLDDR: ddr_sdram_mode_2 = 0x%08x\n", ddr->ddr_sdram_mode_2);
    
    }
    
    /* DDR SDRAM Interval Configuration (DDR_SDRAM_INTERVAL) */
    static void set_ddr_sdram_interval(fsl_ddr_cfg_regs_t *ddr,
    			       const memctl_options_t *popts,
    			       const common_timing_params_t *common_dimm)
    {
    	unsigned int refint;	/* Refresh interval */
    	unsigned int bstopre;	/* Precharge interval */
    
    	refint = picos_to_mclk(common_dimm->refresh_rate_ps);
    
    	bstopre = popts->bstopre;
    
    	/* refint field used 0x3FFF in earlier controllers */
    	ddr->ddr_sdram_interval = (0
    				   | ((refint & 0xFFFF) << 16)
    				   | ((bstopre & 0x3FFF) << 0)
    				   );
    
    	debug("FSLDDR: ddr_sdram_interval = 0x%08x\n", ddr->ddr_sdram_interval);
    
    #if defined(CONFIG_FSL_DDR3)
    /* DDR SDRAM Mode configuration set (DDR_SDRAM_MODE) */
    static void set_ddr_sdram_mode(fsl_ddr_cfg_regs_t *ddr,
    			       const memctl_options_t *popts,
    			       const common_timing_params_t *common_dimm,
    			       unsigned int cas_latency,
    			       unsigned int additive_latency)
    {
    	unsigned short esdmode;		/* Extended SDRAM mode */
    	unsigned short sdmode;		/* SDRAM mode */
    
    	/* Mode Register - MR1 */
    	unsigned int qoff = 0;		/* Output buffer enable 0=yes, 1=no */
    	unsigned int tdqs_en = 0;	/* TDQS Enable: 0=no, 1=yes */
    	unsigned int rtt;
    	unsigned int wrlvl_en = 0;	/* Write level enable: 0=no, 1=yes */
    	unsigned int al = 0;		/* Posted CAS# additive latency (AL) */
    	unsigned int dic = 1;		/* Output driver impedance, 34ohm */
    	unsigned int dll_en = 0;	/* DLL Enable  0=Enable (Normal),
    						       1=Disable (Test/Debug) */
    
    	/* Mode Register - MR0 */
    	unsigned int dll_on;	/* DLL control for precharge PD, 0=off, 1=on */
    	unsigned int wr;	/* Write Recovery */
    	unsigned int dll_rst;	/* DLL Reset */
    	unsigned int mode;	/* Normal=0 or Test=1 */
    	unsigned int caslat = 4;/* CAS# latency, default set as 6 cycles */
    	/* BT: Burst Type (0=Nibble Sequential, 1=Interleaved) */
    	unsigned int bt;
    	unsigned int bl;	/* BL: Burst Length */
    
    	unsigned int wr_mclk;
    
    	const unsigned int mclk_ps = get_memory_clk_period_ps();
    
    	rtt = fsl_ddr_get_rtt();
    	if (popts->rtt_override)
    		rtt = popts->rtt_override_value;
    
    	if (additive_latency == (cas_latency - 1))
    		al = 1;
    	if (additive_latency == (cas_latency - 2))
    		al = 2;
    
    	/*
    	 * The esdmode value will also be used for writing
    	 * MR1 during write leveling for DDR3, although the
    	 * bits specifically related to the write leveling
    	 * scheme will be handled automatically by the DDR
    	 * controller. so we set the wrlvl_en = 0 here.
    	 */
    	esdmode = (0
    		| ((qoff & 0x1) << 12)
    		| ((tdqs_en & 0x1) << 11)
    
    		| ((rtt & 0x4) << 7)   /* rtt field is split */
    
    		| ((wrlvl_en & 0x1) << 7)
    
    		| ((rtt & 0x2) << 5)   /* rtt field is split */
    		| ((dic & 0x2) << 4)   /* DIC field is split */
    
    		| ((al & 0x3) << 3)
    
    		| ((rtt & 0x1) << 2)  /* rtt field is split */
    
    		| ((dic & 0x1) << 1)   /* DIC field is split */
    		| ((dll_en & 0x1) << 0)
    		);
    
    	/*
    	 * DLL control for precharge PD
    	 * 0=slow exit DLL off (tXPDLL)
    	 * 1=fast exit DLL on (tXP)
    	 */
    	dll_on = 1;
    	wr_mclk = (common_dimm->tWR_ps + mclk_ps - 1) / mclk_ps;
    	if (wr_mclk >= 12)
    		wr = 6;
    	else if (wr_mclk >= 9)
    		wr = 5;
    	else
    		wr = wr_mclk - 4;
    	dll_rst = 0;	/* dll no reset */
    	mode = 0;	/* normal mode */
    
    	/* look up table to get the cas latency bits */
    	if (cas_latency >= 5 && cas_latency <= 11) {
    		unsigned char cas_latency_table[7] = {
    			0x2,	/* 5 clocks */
    			0x4,	/* 6 clocks */
    			0x6,	/* 7 clocks */
    			0x8,	/* 8 clocks */
    			0xa,	/* 9 clocks */
    			0xc,	/* 10 clocks */
    			0xe	/* 11 clocks */
    		};
    		caslat = cas_latency_table[cas_latency - 5];
    	}
    	bt = 0;	/* Nibble sequential */
    
    	switch (popts->burst_length) {
    	case DDR_BL8:
    		bl = 0;
    		break;
    	case DDR_OTF:
    		bl = 1;
    		break;
    	case DDR_BC4:
    		bl = 2;
    		break;
    	default:
    		printf("Error: invalid burst length of %u specified. "
    			" Defaulting to on-the-fly BC4 or BL8 beats.\n",
    			popts->burst_length);
    		bl = 1;
    		break;
    	}
    
    	sdmode = (0
    		  | ((dll_on & 0x1) << 12)
    		  | ((wr & 0x7) << 9)
    		  | ((dll_rst & 0x1) << 8)
    		  | ((mode & 0x1) << 7)
    		  | (((caslat >> 1) & 0x7) << 4)
    		  | ((bt & 0x1) << 3)
    		  | ((bl & 0x3) << 0)
    		  );
    
    	ddr->ddr_sdram_mode = (0
    			       | ((esdmode & 0xFFFF) << 16)
    			       | ((sdmode & 0xFFFF) << 0)
    			       );
    
    	debug("FSLDDR: ddr_sdram_mode = 0x%08x\n", ddr->ddr_sdram_mode);
    }
    
    #else /* !CONFIG_FSL_DDR3 */
    
    
    /* DDR SDRAM Mode configuration set (DDR_SDRAM_MODE) */
    static void set_ddr_sdram_mode(fsl_ddr_cfg_regs_t *ddr,
    			       const memctl_options_t *popts,
    			       const common_timing_params_t *common_dimm,
    			       unsigned int cas_latency,
    			       unsigned int additive_latency)
    {
    	unsigned short esdmode;		/* Extended SDRAM mode */
    	unsigned short sdmode;		/* SDRAM mode */
    
    	/*
    	 * FIXME: This ought to be pre-calculated in a
    	 * technology-specific routine,
    	 * e.g. compute_DDR2_mode_register(), and then the
    	 * sdmode and esdmode passed in as part of common_dimm.
    	 */
    
    	/* Extended Mode Register */
    	unsigned int mrs = 0;		/* Mode Register Set */
    	unsigned int outputs = 0;	/* 0=Enabled, 1=Disabled */
    	unsigned int rdqs_en = 0;	/* RDQS Enable: 0=no, 1=yes */
    	unsigned int dqs_en = 0;	/* DQS# Enable: 0=enable, 1=disable */
    	unsigned int ocd = 0;		/* 0x0=OCD not supported,
    					   0x7=OCD default state */
    	unsigned int rtt;
    	unsigned int al;		/* Posted CAS# additive latency (AL) */
    	unsigned int ods = 0;		/* Output Drive Strength:
    						0 = Full strength (18ohm)
    						1 = Reduced strength (4ohm) */
    	unsigned int dll_en = 0;	/* DLL Enable  0=Enable (Normal),
    						       1=Disable (Test/Debug) */
    
    	/* Mode Register (MR) */
    	unsigned int mr;	/* Mode Register Definition */
    	unsigned int pd;	/* Power-Down Mode */
    	unsigned int wr;	/* Write Recovery */
    	unsigned int dll_res;	/* DLL Reset */
    	unsigned int mode;	/* Normal=0 or Test=1 */
    
    	unsigned int caslat = 0;/* CAS# latency */
    
    	/* BT: Burst Type (0=Sequential, 1=Interleaved) */
    	unsigned int bt;
    	unsigned int bl;	/* BL: Burst Length */
    
    #if defined(CONFIG_FSL_DDR2)
    	const unsigned int mclk_ps = get_memory_clk_period_ps();
    #endif
    
    	rtt = fsl_ddr_get_rtt();
    
    	al = additive_latency;
    
    	esdmode = (0
    		| ((mrs & 0x3) << 14)
    		| ((outputs & 0x1) << 12)
    		| ((rdqs_en & 0x1) << 11)
    		| ((dqs_en & 0x1) << 10)
    		| ((ocd & 0x7) << 7)
    		| ((rtt & 0x2) << 5)   /* rtt field is split */
    		| ((al & 0x7) << 3)
    		| ((rtt & 0x1) << 2)   /* rtt field is split */
    		| ((ods & 0x1) << 1)
    		| ((dll_en & 0x1) << 0)
    		);
    
    	mr = 0;		 /* FIXME: CHECKME */
    
    	/*
    	 * 0 = Fast Exit (Normal)
    	 * 1 = Slow Exit (Low Power)
    	 */
    	pd = 0;
    
    #if defined(CONFIG_FSL_DDR1)
    	wr = 0;       /* Historical */
    #elif defined(CONFIG_FSL_DDR2)
    	wr = (common_dimm->tWR_ps + mclk_ps - 1) / mclk_ps - 1;
    #endif
    	dll_res = 0;
    	mode = 0;
    
    #if defined(CONFIG_FSL_DDR1)
    	if (1 <= cas_latency && cas_latency <= 4) {
    		unsigned char mode_caslat_table[4] = {
    			0x5,	/* 1.5 clocks */
    			0x2,	/* 2.0 clocks */
    			0x6,	/* 2.5 clocks */
    			0x3	/* 3.0 clocks */
    		};
    
    		caslat = mode_caslat_table[cas_latency - 1];
    	} else {
    		printf("Warning: unknown cas_latency %d\n", cas_latency);
    
    	}
    #elif defined(CONFIG_FSL_DDR2)
    	caslat = cas_latency;
    #endif
    	bt = 0;
    
    	switch (popts->burst_length) {
    
    	case DDR_BL4:
    
    	case DDR_BL8:
    
    		bl = 3;
    		break;
    	default:
    		printf("Error: invalid burst length of %u specified. "
    			" Defaulting to 4 beats.\n",
    			popts->burst_length);
    		bl = 2;
    		break;
    	}
    
    	sdmode = (0
    		  | ((mr & 0x3) << 14)
    		  | ((pd & 0x1) << 12)
    		  | ((wr & 0x7) << 9)
    		  | ((dll_res & 0x1) << 8)
    		  | ((mode & 0x1) << 7)
    		  | ((caslat & 0x7) << 4)
    		  | ((bt & 0x1) << 3)
    		  | ((bl & 0x7) << 0)
    		  );
    
    	ddr->ddr_sdram_mode = (0
    			       | ((esdmode & 0xFFFF) << 16)
    			       | ((sdmode & 0xFFFF) << 0)
    			       );
    
    	debug("FSLDDR: ddr_sdram_mode = 0x%08x\n", ddr->ddr_sdram_mode);
    
    
    /* DDR SDRAM Data Initialization (DDR_DATA_INIT) */
    static void set_ddr_data_init(fsl_ddr_cfg_regs_t *ddr)
    {
    	unsigned int init_value;	/* Initialization value */
    
    	init_value = 0xDEADBEEF;
    	ddr->ddr_data_init = init_value;
    }
    
    /*
     * DDR SDRAM Clock Control (DDR_SDRAM_CLK_CNTL)
     * The old controller on the 8540/60 doesn't have this register.
     * Hope it's OK to set it (to 0) anyway.
     */
    static void set_ddr_sdram_clk_cntl(fsl_ddr_cfg_regs_t *ddr,
    					 const memctl_options_t *popts)
    {
    	unsigned int clk_adjust;	/* Clock adjust */
    
    	clk_adjust = popts->clk_adjust;
    	ddr->ddr_sdram_clk_cntl = (clk_adjust & 0xF) << 23;
    }
    
    /* DDR Initialization Address (DDR_INIT_ADDR) */
    static void set_ddr_init_addr(fsl_ddr_cfg_regs_t *ddr)
    {
    	unsigned int init_addr = 0;	/* Initialization address */
    
    	ddr->ddr_init_addr = init_addr;
    }
    
    /* DDR Initialization Address (DDR_INIT_EXT_ADDR) */
    static void set_ddr_init_ext_addr(fsl_ddr_cfg_regs_t *ddr)
    {
    	unsigned int uia = 0;	/* Use initialization address */
    	unsigned int init_ext_addr = 0;	/* Initialization address */
    
    	ddr->ddr_init_ext_addr = (0
    				  | ((uia & 0x1) << 31)
    				  | (init_ext_addr & 0xF)
    				  );
    }
    
    /* DDR SDRAM Timing Configuration 4 (TIMING_CFG_4) */
    
    static void set_timing_cfg_4(fsl_ddr_cfg_regs_t *ddr,
    				const memctl_options_t *popts)
    
    {
    	unsigned int rwt = 0; /* Read-to-write turnaround for same CS */
    	unsigned int wrt = 0; /* Write-to-read turnaround for same CS */
    	unsigned int rrt = 0; /* Read-to-read turnaround for same CS */
    	unsigned int wwt = 0; /* Write-to-write turnaround for same CS */
    	unsigned int dll_lock = 0; /* DDR SDRAM DLL Lock Time */
    
    
    #if defined(CONFIG_FSL_DDR3)
    
    	if (popts->burst_length == DDR_BL8) {
    		/* We set BL/2 for fixed BL8 */
    		rrt = 0;	/* BL/2 clocks */
    		wwt = 0;	/* BL/2 clocks */
    	} else {
    		/* We need to set BL/2 + 2 to BC4 and OTF */
    		rrt = 2;	/* BL/2 + 2 clocks */
    		wwt = 2;	/* BL/2 + 2 clocks */
    	}
    
    	dll_lock = 1;	/* tDLLK = 512 clocks from spec */
    #endif
    
    	ddr->timing_cfg_4 = (0
    			     | ((rwt & 0xf) << 28)
    			     | ((wrt & 0xf) << 24)
    			     | ((rrt & 0xf) << 20)
    			     | ((wwt & 0xf) << 16)
    			     | (dll_lock & 0x3)
    			     );
    
    	debug("FSLDDR: timing_cfg_4 = 0x%08x\n", ddr->timing_cfg_4);
    
    }
    
    /* DDR SDRAM Timing Configuration 5 (TIMING_CFG_5) */
    static void set_timing_cfg_5(fsl_ddr_cfg_regs_t *ddr)
    {
    	unsigned int rodt_on = 0;	/* Read to ODT on */
    	unsigned int rodt_off = 0;	/* Read to ODT off */
    	unsigned int wodt_on = 0;	/* Write to ODT on */