We are bringing up a new board with a DM3730 and do not see I2C transitions on any of the ports. Our design was based on the BeagleBoard C4 with regards to the processor and the TPS65950 PMIC. We populated our board with a DM3730CBP. We are using U-Boot for the beagle board ported to our platform. When built for the BeagleBoard, I2C operates fine but when built for our platform, we fail to see transitions on the SCL lines. We have verified mux settings, for example on I2C1(printout during i2c_write_byte):
GPIO 12c1 SCL Mux Setting (0x480021b8) =180108
GPIO 12c1 SDA Mux Setting (0x480021bC)v=180118
We have verified pin operations in two ways: we have seen I2C SCL transitions as ROM code executes and looks for the bootloader on MMC1 and we have changed SCL on I2C2 to a GPIO and manually toggled the pin by writing to registers. Other peripherals appear to work (we use UART for U-boot console, MMC1 to load the x-loader and u-boot, and have verified SPI clock transitions). Does anyone know of a special clock connection on the AM37 vs. the AM35 or of a special hardware requirement that would prevent just the I2C from driving the I/O lines?
