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// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2000-2003
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* Copyright (C) 2004-2007, 2012 Freescale Semiconductor, Inc.
* TsiChung Liew (Tsi-Chung.Liew@freescale.com)
*/
#include <config.h>
#include <common.h>
#include <asm/immap.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
int checkboard(void)
{
puts("Board: ");
puts("Freescale M5235 EVB\n");
return 0;
};
int dram_init(void)
{
sdram_t *sdram = (sdram_t *)(MMAP_SDRAM);
gpio_t *gpio = (gpio_t *)(MMAP_GPIO);
u32 dramsize, i, dramclk;
/*
* When booting from external Flash, the port-size is less than
* the port-size of SDRAM. In this case it is necessary to enable
* Data[15:0] on Port Address/Data.
*/
out_8(&gpio->par_ad,
GPIO_PAR_AD_ADDR23 | GPIO_PAR_AD_ADDR22 | GPIO_PAR_AD_ADDR21 |
GPIO_PAR_AD_DATAL);
/* Initialize PAR to enable SDRAM signals */
out_8(&gpio->par_sdram,
GPIO_PAR_SDRAM_SDWE | GPIO_PAR_SDRAM_SCAS |
GPIO_PAR_SDRAM_SRAS | GPIO_PAR_SDRAM_SCKE |
GPIO_PAR_SDRAM_SDCS(3));
dramsize = CONFIG_SYS_SDRAM_SIZE * 0x100000;
for (i = 0x13; i < 0x20; i++) {
if (dramsize == (1 << i))
break;
}
i--;
if (!(in_be32(&sdram->dacr0) & SDRAMC_DARCn_RE)) {
dramclk = gd->bus_clk / (CONFIG_SYS_HZ * CONFIG_SYS_HZ);
/* Initialize DRAM Control Register: DCR */
out_be16(&sdram->dcr, SDRAMC_DCR_RTIM_9CLKS |
SDRAMC_DCR_RTIM_6CLKS |
SDRAMC_DCR_RC((15 * dramclk) >> 4));
/* Initialize DACR0 */
out_be32(&sdram->dacr0,
SDRAMC_DARCn_BA(CONFIG_SYS_SDRAM_BASE) |
SDRAMC_DARCn_CASL_C1 | SDRAMC_DARCn_CBM_CMD20 |
SDRAMC_DARCn_PS_32);
asm("nop");
/* Initialize DMR0 */
out_be32(&sdram->dmr0,
((dramsize - 1) & 0xFFFC0000) | SDRAMC_DMRn_V);
asm("nop");
/* Set IP (bit 3) in DACR */
setbits_be32(&sdram->dacr0, SDRAMC_DARCn_IP);
/* 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;
/* Set RE (bit 15) in DACR */
setbits_be32(&sdram->dacr0, SDRAMC_DARCn_RE);
/* Wait for at least 8 auto refresh cycles to occur */
for (i = 0; i < 0x2000; i++) {
asm("nop");
}
/* Finish the configuration by issuing the MRS. */
setbits_be32(&sdram->dacr0, SDRAMC_DARCn_IMRS);
asm("nop");
/* Write to the SDRAM Mode Register */
*(u32 *) (CONFIG_SYS_SDRAM_BASE + 0x400) = 0xA5A59696;
}
gd->ram_size = dramsize;
return 0;
};
int testdram(void)
{
/* TODO: XXX XXX XXX */
printf("DRAM test not implemented!\n");
return (0);
}
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