board/freescale/mpc8308rdb/sdram.c

/*
 * Copyright (C) 2007 Freescale Semiconductor, Inc.
 * Copyright (C) 2010 Ilya Yanok, Emcraft Systems, yanok@emcraft.com
 *
 * Authors: Nick.Spence@freescale.com
 *          Wilson.Lo@freescale.com
 *          scottwood@freescale.com
 *
 * This files is  mostly identical to the original from
 * board\freescale\mpc8315erdb\sdram.c
 *
 * 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 <mpc83xx.h>

#include <asm/bitops.h>
#include <asm/io.h>

#include <asm/processor.h>

DECLARE_GLOBAL_DATA_PTR;

static void resume_from_sleep(void)
{
	u32 magic = *(u32 *)0;

	typedef void (*func_t)(void);
	func_t resume = *(func_t *)4;

	if (magic == 0xf5153ae5)
		resume();

	gd->flags &= ~GD_FLG_SILENT;
	puts("\nResume from sleep failed: bad magic word\n");
}

/* Fixed sdram init -- doesn't use serial presence detect.
 *
 * This is useful for faster booting in configs where the RAM is unlikely
 * to be changed, or for things like NAND booting where space is tight.
 */
static long fixed_sdram(void)
{
	immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
	u32 msize = CONFIG_SYS_DDR_SIZE * 1024 * 1024;
	u32 msize_log2 = __ilog2(msize);

	out_be32(&im->sysconf.ddrlaw[0].bar,
			CONFIG_SYS_DDR_SDRAM_BASE  & 0xfffff000);
	out_be32(&im->sysconf.ddrlaw[0].ar, LBLAWAR_EN | (msize_log2 - 1));
	out_be32(&im->sysconf.ddrcdr, CONFIG_SYS_DDRCDR_VALUE);

	/*
	 * Erratum DDR3 requires a 50ms delay after clearing DDRCDR[DDR_cfg],
	 * or the DDR2 controller may fail to initialize correctly.
	 */
	udelay(50000);

	out_be32(&im->ddr.csbnds[0].csbnds, (msize - 1) >> 24);
	out_be32(&im->ddr.cs_config[0], CONFIG_SYS_DDR_CS0_CONFIG);

	/* Currently we use only one CS, so disable the other bank. */
	out_be32(&im->ddr.cs_config[1], 0);

	out_be32(&im->ddr.sdram_clk_cntl, CONFIG_SYS_DDR_SDRAM_CLK_CNTL);
	out_be32(&im->ddr.timing_cfg_3, CONFIG_SYS_DDR_TIMING_3);
	out_be32(&im->ddr.timing_cfg_1, CONFIG_SYS_DDR_TIMING_1);
	out_be32(&im->ddr.timing_cfg_2, CONFIG_SYS_DDR_TIMING_2);
	out_be32(&im->ddr.timing_cfg_0, CONFIG_SYS_DDR_TIMING_0);

	if (in_be32(&im->pmc.pmccr1) & PMCCR1_POWER_OFF) {
		out_be32(&im->ddr.sdram_cfg,
			CONFIG_SYS_DDR_SDRAM_CFG | SDRAM_CFG_BI);
	} else {
		out_be32(&im->ddr.sdram_cfg, CONFIG_SYS_DDR_SDRAM_CFG);
	}

	out_be32(&im->ddr.sdram_cfg2, CONFIG_SYS_DDR_SDRAM_CFG2);
	out_be32(&im->ddr.sdram_mode, CONFIG_SYS_DDR_MODE);
	out_be32(&im->ddr.sdram_mode2, CONFIG_SYS_DDR_MODE2);

	out_be32(&im->ddr.sdram_interval, CONFIG_SYS_DDR_INTERVAL);
	sync();

	/* enable DDR controller */
	setbits_be32(&im->ddr.sdram_cfg, SDRAM_CFG_MEM_EN);
	sync();

	return get_ram_size(CONFIG_SYS_DDR_SDRAM_BASE, msize);
}

phys_size_t initdram(int board_type)
{
	immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
	u32 msize;

	if ((in_be32(&im->sysconf.immrbar) & IMMRBAR_BASE_ADDR) != (u32)im)
		return -1;

	/* DDR SDRAM */
	msize = fixed_sdram();

	if (in_be32(&im->pmc.pmccr1) & PMCCR1_POWER_OFF)
		resume_from_sleep();

	/* return total bus SDRAM size(bytes)  -- DDR */
	return msize;
}