OOh @tworaz you know what?
“PMU Interrupt GPIO1_C5 is relocated here”
Coincidence or what? 
On the DevTerm schematics though, GPIO3_B2 is connected to DDR2 pin 5, marked “GPIO0”, then to PMU-SDA (AXP228 not rk808)
| Pin | RockPro64 sch | PineBookPro sch | DevTerm sch |
|---|---|---|---|
| GPIO1_C5 | NC | I2C8_SCL (PI-2 bus) | rk808 PMIC_INT_L(??) |
| GPIO3_B2 | rk808 PMIC_INT_L | rk808 PMIC_INT_L | axp228 PMU-SDA |
| GPIO3_B3 | NC | MAC_CLK | axp228 PMU-SCK |
| GPIO3_B0 | NC | MAC_MDC | axp228 PMU-IRQ |
So both PBP and RkP64 “moved” from GPIO1_C5 to GPIO3_B2, but that is occupied on DT by axp228
The devterm device tree also enables sdio0_bus4 that configures RK_PC5.
The devterm device tree configures RK_PC5 to be pull-up, so if it’s not connected it should at least stay high.