On Sunday, November 15, 2015 at 10:47:12 PM, Michael Heimpold wrote: > At the moment, the desired brownout is at 1.0V. However, > this setting cannot be realized by hardware since we have > only 3 bits to represent the voltage difference from the > target value. > > Target value is 1500 mV, brownout target is 1000 mV, > voltage steps are 25 mV. > > Register content calculation: > (1500 [mV] - 1000 [mV]) / 25 [mV] = 20 (decimal) = 0x14 > > Register takes only 3 bits, that is 0x4. > > But 0x4 * 25 [mV] = 100 [mV], that means that actual > brownout level is 1500 [mV] - 100 [mV] = 1.4 V. > > Minimum possible BO level is > 1500 [mV] - 0x7 * 25 [mV] = 1315 [mV]. > > So lets use this value as desired BO value (which is > also the same as FSL bootlets use). > > Signed-off-by: Michael Heimpold <[email protected]> > Cc: Marek Vasut <[email protected]> > Cc: Otavio Salvador <[email protected]> > Cc: Fabio Estevam <[email protected]>
Uh, nice find. How did you find it? Acked-by: Marek Vasut <[email protected]> Best regards, Marek Vasut _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
