hi,
we are going to use the STPMIC1E in our design but bc the part is not available we are going to use the STPMIC1B for the initial boards we produce and then change to the desired part.
however, the buck4 regulator needs to be changed to 1.2 volts from 3.3 volts. we want to change the device tree's entry for the pmic so that the buck4 regulator is configured for 1.2 volts.
we are using the eval board 1 while we wait for the boards to be built. we changed the buck4's setting from 3.3 volts to 3.29 volts. but this caused problems when the board was booting up as can be seen from the uboot log below (the errors are in bold):
[ 3.180437] stm32_rtc 5c004000.rtc: registered as rtc0
[ 3.184181] stm32_rtc 5c004000.rtc: setting system clock to 2021-12-09T18:10:15 UTC (1639073415)
[ 3.193372] stm32_rtc 5c004000.rtc: registered rev:1.2
[ 3.224807] stm32f7-i2c 40013000.i2c: STM32F7 I2C-0 bus adapter
[ 3.246840] stm32f7-i2c 40015000.i2c: STM32F7 I2C-1 bus adapter
[ 3.273846] stpmic1 2-0033: PMIC Chip Version: 0x20
[ 3.285441] vddcore: supplied by vin
[ 3.290634] vdd_ddr: supplied by vin
[ 3.295698] vdd: supplied by vin
[ 3.297957] v3v3: Bringing 3300000uV into 3290000-3290000uV
[ 3.303041] v3v3: failed to apply 3290000-3290000uV constraint: -EINVAL
[ 3.309699] stpmic1-regulator 5c002000.i2c:stpmic@33:regulators: failed to register BUCK4 regulator
[ 3.319620] stpmic1-regulator: probe of 5c002000.i2c:stpmic@33:regulators failed with error -22
[ 3.330990] input: pmic_onkey as /devices/platform/soc/5c002000.i2c/i2c-2/2-0033/5c002000.i2c:stpm0
[ 3.341679] stm32f7-i2c 5c002000.i2c: STM32F7 I2C-2 bus adapter
[ 3.348681] mmci-pl18x 58005000.sdmmc: Got CD GPIO
[ 3.357446] stm32-ipcc 4c001000.mailbox: ipcc rev:1.0 enabled, 6 chans, proc 0
[ 3.364917] stm32-rproc 10000000.m4: wdg irq registered
[ 3.369504] remoteproc remoteproc0: m4 is available
[ 3.377995] nand: device found, Manufacturer ID: 0x2c, Chip ID: 0xd3
[ 3.382900] nand: Micron MT29F8G08ABACAH4
[ 3.386903] nand: 1024 MiB, SLC, erase size: 256 KiB, page size: 4096, OOB size: 224
[ 3.395295] Bad block table found at page 262080, version 0x01
[ 3.400897] Bad block table found at page 262016, version 0x01
[ 3.417956] mmci-pl18x 58005000.sdmmc: Got CD GPIO
[ 3.430569] Goodix-TS 0-005d: deferred probe timeout, ignoring dependency
[ 3.437838] mmci-pl18x 58005000.sdmmc: Got CD GPIO
[ 3.445061] gpio-keys joystick: deferred probe timeout, ignoring dependency
[ 3.454588] Freeing unused kernel memory: 1024K
[ 3.467960] Run /init as init process
Starting version 244.5+
root '/dev/disk/by-partuuid/e91c4e10-16e6-4c0e-bd0e-77becf4a3582' doesn't exist or does not contain a.
[ 33.767613] reg11: disabling
[ 33.769051] reg18: disabling
[ 33.771914] usb33: disabling
what we would like to know is how to change the settings for the pmic's voltage regulators so that the board is able to boot up w/ new voltages. it seems that there are other dependencies elsewhere in the linux kernel that require changes. we would like to know what those are so that we can make these changes for our custom board.
thanks,
vince
