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ColdFire: M5271EVB DRAM Bring up issue

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Fix proper portsize: The register for portsize is either 00b, 01b,
or 1xb. The value that previous assigned is 32d.
Fix DRAM bring up: insert asm("nop") for every DRAM register setup

Signed-off-by: TsiChung Liew <tsicliew@gmail.com>
This commit is contained in:
TsiChung Liew 2010-03-10 16:14:01 -06:00
parent ac265f7fca
commit 53e4290f20
1 changed files with 10 additions and 2 deletions
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12
board/freescale/m5271evb/m5271evb.c
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@ -47,6 +47,7 @@ phys_size_t initdram (int board_type) {
MCF_GPIO_SDRAM_SDWE | MCF_GPIO_SDRAM_SCAS |
MCF_GPIO_SDRAM_SRAS | MCF_GPIO_SDRAM_SCKE |
MCF_GPIO_SDRAM_SDCS_11);
asm(" nop");
/*
* Check to see if the SDRAM has already been initialized
@ -55,8 +56,9 @@ phys_size_t initdram (int board_type) {
if (!(mbar_readLong(MCF_SDRAMC_DACR0) & MCF_SDRAMC_DACRn_RE)) {
/* Initialize DRAM Control Register: DCR */
mbar_writeShort(MCF_SDRAMC_DCR,
MCF_SDRAMC_DCR_RTIM(0x01)
| MCF_SDRAMC_DCR_RC(0x30));
MCF_SDRAMC_DCR_RTIM(2)
| MCF_SDRAMC_DCR_RC(0x2E));
asm(" nop");
/*
* Initialize DACR0
@ -70,15 +72,18 @@ phys_size_t initdram (int board_type) {
| MCF_SDRAMC_DACRn_CASL(1)
| MCF_SDRAMC_DACRn_CBM(3)
| MCF_SDRAMC_DACRn_PS(0));
asm(" nop");
/* Initialize DMR0 */
mbar_writeLong(MCF_SDRAMC_DMR0,
MCF_SDRAMC_DMRn_BAM_16M
| MCF_SDRAMC_DMRn_V);
asm(" nop");
/* Set IP bit in DACR */
mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
| MCF_SDRAMC_DACRn_IP);
asm(" nop");
/* Wait at least 20ns to allow banks to precharge */
for (i = 0; i < 5; i++)
@ -86,6 +91,7 @@ phys_size_t initdram (int board_type) {
/* Write to this block to initiate precharge */
*(u32 *)(CONFIG_SYS_SDRAM_BASE) = 0xa5a5a5a5;
asm(" nop");
/* Set RE bit in DACR */
mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
@ -98,6 +104,7 @@ phys_size_t initdram (int board_type) {
/* Finish the configuration by issuing the MRS */
mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
| MCF_SDRAMC_DACRn_MRS);
asm(" nop");
/*
* Write to the SDRAM Mode Register A0-A11 = 0x400
@ -109,6 +116,7 @@ phys_size_t initdram (int board_type) {
* Burst Length = 1
*/
*(u32 *)(CONFIG_SYS_SDRAM_BASE + 0x400) = 0xa5a5a5a5;
asm(" nop");
}
return CONFIG_SYS_SDRAM_SIZE * 1024 * 1024;