On Wednesday, June 18, 2014 at 08:17:05 PM, Peter Schumann wrote:
Am 17.06.2014 18:00, schrieb Stefano Babic:
Hi peter, ... On 17/06/2014 00:19, Marek Vasut wrote: Agree. Reason is that this change is for all boards, and without a proper testing I will avoid to merge it in the release.
Best regards, Stefano Babic
Hi Stefano,
I've only the imx233 olimex board for testing. The DOUBLE_FETS switch in HW_POWER_MINPWR is some thing were maybe problems emerge.
I have very little load on the powerrails (imx233 + DRAM), so maybe with more current demand DOUBLE_FETS is working OK and even more may require it to be set.
If that was the case, the problem would manifest even when _not_ booting from battery-only supply, correct?
The DOUBLE_FETS and HALF_FETS switches control the switching MOSFET size in the DCDC Converter. My assumption is that if we have a to big FET setting and to low current demand we trigger some failsafe mechanism. Because the required "on time" of the FET is smaller than the minimum possible "on time" of then DCDC FET control logic.
I don't have an easy way to test this assumption without an adjustable load.
The other change regarding mxs_power_enable_4p2() should be relatively safe to apply.
This breaks booting from battery on MX28 for some reason. The DC converter is not enabled at that point.
Best regards, Marek Vasut