Hi, > Am 06.09.2019 um 05:01 schrieb Viresh Kumar <viresh.kumar@xxxxxxxxxx>: > > On 05-09-19, 07:32, Tony Lindgren wrote: >> * H. Nikolaus Schaller <hns@xxxxxxxxxxxxx> [190904 08:54]: >>> This adds code and tables to read the silicon revision and >>> eFuse (speed binned / 720 MHz grade) bits for selecting >>> opp-v2 table entries. >>> >>> Since these bits are not always part of the syscon register >>> range (like for am33xx, am43, dra7), we add code to directly >>> read the register values using ioremap() if syscon access fails. >> >> This is nice :) Seems to work for me based on a quick test >> on at least omap36xx. >> >> Looks like n900 produces the following though: >> >> core: _opp_supported_by_regulators: OPP minuV: 1270000 maxuV: 1270000, not supported by regulator >> cpu cpu0: _opp_add: OPP not supported by regulators (550000000) > > That's a DT thing I believe where the voltage doesn't fit what the > regulator can support. I can confirm this on BeagleBoard C2: root@gta04:~# dmesg|fgrep -i opp [ 2.347442] core: _opp_supported_by_regulators: OPP minuV: 1270000 maxuV: 1270000, not supported by regulator [ 2.359222] cpu cpu0: _opp_add: OPP not supported by regulators (550000000) [ 2.580993] omap2_set_init_voltage: unable to find boot up OPP for vdd_core root@gta04:~# > >> But presumably that can be further patched. Well, the opp-v1 table also has this voltage point: /* OMAP343x/OMAP35xx variants OPP1-5 */ operating-points = < /* kHz uV */ 125000 975000 250000 1075000 500000 1200000 550000 1270000 600000 1350000 >; This is OPP4 which is recommended by OMAP3530 data sheet to be 1.27V +/- 5% Data sheet of tps65950 says • VDD1: 1.2-A, buck DC/DC converter (VOUT = 0.6 V to 1.45 V, in steps of 12.5 mV) This means 1270 mV is not a "step" and rejected by the twl4030 driver. Maybe nobody did notice yet because the opp-v1 drivers did not warn... The closest value to 1.27V is 0.6V + 54 * 12.5mV is 1.275V So let's also change the OPP4 to 1275000 uV in the opp-v2 table. BR and thanks, Nikolaus
