am33xx: Update DDR3 EMIF configuration sequence

Based on
http://processors.wiki.ti.com/index.php/AM335x_EMIF_Configuration_tips
we need to re-work our sequence in config_sdram slightly to match what
the TRM describes as the correct sequence.  In our current (incorrect)
sequence some edge cases may fail to initalize correctly.

Signed-off-by: Tom Rini <trini@ti.com>
This commit is contained in:
Tom Rini 2013-02-26 16:35:33 -05:00
parent 98bc1228c8
commit 1c382ead7a

View File

@ -45,13 +45,19 @@ static struct ddr_cmdtctrl *ioctrl_reg = {
*/
void config_sdram(const struct emif_regs *regs)
{
writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl);
writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl_shdw);
if (regs->zq_config){
if (regs->zq_config) {
/*
* A value of 0x2800 for the REF CTRL will give us
* about 570us for a delay, which will be long enough
* to configure things.
*/
writel(0x2800, &emif_reg->emif_sdram_ref_ctrl);
writel(regs->zq_config, &emif_reg->emif_zq_config);
writel(regs->sdram_config, &cstat->secure_emif_sdram_config);
}
writel(regs->sdram_config, &emif_reg->emif_sdram_config);
writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl);
writel(regs->ref_ctrl, &emif_reg->emif_sdram_ref_ctrl_shdw);
}
/**