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/*
* (C) Copyright 2000-2003
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/immap.h>
DECLARE_GLOBAL_DATA_PTR;
int checkboard (void)
{
puts ("Board: Freescale M5282EVB Evaluation Board\n");
return 0;
}
int dram_init(void)
{
u32 dramsize, i, dramclk;
dramsize = CONFIG_SYS_SDRAM_SIZE * 0x100000;
for (i = 0x13; i < 0x20; i++) {
if (dramsize == (1 << i))
break;
}
i--;
if (!(MCFSDRAMC_DACR0 & MCFSDRAMC_DACR_RE))
{
dramclk = gd->bus_clk / (CONFIG_SYS_HZ * CONFIG_SYS_HZ);
/* Initialize DRAM Control Register: DCR */
MCFSDRAMC_DCR = (0
| MCFSDRAMC_DCR_RTIM_6
| MCFSDRAMC_DCR_RC((15 * dramclk)>>4));
asm("nop");
/* Initialize DACR0 */
MCFSDRAMC_DACR0 = (0
| MCFSDRAMC_DACR_BASE(CONFIG_SYS_SDRAM_BASE)
| MCFSDRAMC_DACR_CASL(1)
| MCFSDRAMC_DACR_CBM(3)
| MCFSDRAMC_DACR_PS_32);
asm("nop");
/* Initialize DMR0 */
MCFSDRAMC_DMR0 = (0
| ((dramsize - 1) & 0xFFFC0000)
| MCFSDRAMC_DMR_V);
asm("nop");
/* Set IP (bit 3) in DACR */
MCFSDRAMC_DACR0 |= MCFSDRAMC_DACR_IP;
asm("nop");
/* Wait 30ns to allow banks to precharge */
for (i = 0; i < 5; i++) {
asm ("nop");
}
/* Write to this block to initiate precharge */
*(u32 *)(CONFIG_SYS_SDRAM_BASE) = 0xA5A59696;
asm("nop");
/* Set RE (bit 15) in DACR */
MCFSDRAMC_DACR0 |= MCFSDRAMC_DACR_RE;
asm("nop");
/* Wait for at least 8 auto refresh cycles to occur */
for (i = 0; i < 2000; i++) {
asm(" nop");
}
/* Finish the configuration by issuing the IMRS. */
MCFSDRAMC_DACR0 |= MCFSDRAMC_DACR_IMRS;
asm("nop");
/* Write to the SDRAM Mode Register */
*(u32 *)(CONFIG_SYS_SDRAM_BASE + 0x400) = 0xA5A59696;
}
gd->ram_size = dramsize;
return 0;
}
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