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 _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot