question: mx7ulp - LDO_ENABLED_MODE

Jorge Ramirez-Ortiz, Foundries jorge at foundries.io
Thu Jan 16 21:30:00 CET 2020


Hi Fabio,

I am trying to enable LDO in an imx7ulp based board but somehow the
board locks up as soon I  write to PMC1_RUN (using the init_ldo_mode
sequence).

I think it is interesting that bit PMC0_CTRL_PMC1ON is already set so
I am wondering if you think it is possible - in your experience- that
ROM might have already configured LDO? or was this also the case -
this bit already set- when you tested the feature?

I also noticed that if I dont execute the init_ldo_mode sequence and
just check for the LODEN bit [see snipet below], this is already set
which too seems strange.

any suggestions or thoughts?

thanks in advance!

Jorge


#define PMC0_BASE_ADDR		0x410a1000
#define PMC0_CTRL		0x28
#define PMC0_CTRL_LDOEN		BIT(31)

static bool ldo_mode_is_enabled(void)
{
	unsigned int reg;

	reg = readl(PMC0_BASE_ADDR + PMC0_CTRL);
	if (reg & PMC0_CTRL_LDOEN)
		return true;
	else
		return false;
}


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