* H. Nikolaus Schaller hns@goldelico.com [190911 17:48]:
See DM3730,DM275 data sheet (SPRS685B) footnote (6) in Table 4-19 which says that ABB must be switched to FBB mode when using the OPP1G.
The LOD definition abb_mpu_iva already exists so that we need to add plumbing for vbb-supply = <&abb_mpu_iva> and define two voltage vectors for each OPP so that the abb LDO is also updated by the ti-cpufreq driver.
We also must switch the ti_cpufreq_soc_data to multi_regulator.
Note: reading out the abb reglator voltage to verify that it does do transitions can be done by
cat /sys/devices/platform/68000000.ocp/483072f0.regulator-abb-mpu/regulator/regulator.*/microvolts
Likewise, read the twl4030 provided VDD voltage by
cat /sys/devices/platform/68000000.ocp/48070000.i2c/i2c-0/0-0048/48070000.i2c:twl@48:regulator-vdd1/regulator/regulator.*/microvolts
Note: to check if the ABB FBB is enabled/disabled, check registers
PRM_LDO_ABB_CTRL 0x483072F4 bit 3:0 1=bypass 5=FBB PRM_LDO_ABB_SETUP 0x483072F0 0x00=bypass 0x11=FBB
e.g.
/dev/mem opened. Memory mapped at address 0xb6fe4000. Value at address 0x483072F4 (0xb6fe42f4): 0x3205 /dev/mem opened. Memory mapped at address 0xb6f89000. Value at address 0x483072F4 (0xb6f892f4): 0x3201
Note: omap34xx and am3517 have/need no comparable LDO or mechanism.
Acked-by: Tony Lindgren tony@atomide.com