1. An integrated circuit (IC), comprising: configuration memory; programmable logic resources coupled to the configuration memory; programmable interconnection resources coupled to the configuration memory and programmable logic resources; and a configuration controller circuit coupled to the configuration memory, the configuration controller circuit configured to: read values from a configuration memory address of a portion of the configuration memory in response to a configuration memory address contained in input configuration data; decrypt the input configuration data using the values as a decryption key; and program the configuration memory with the decrypted input configuration data, wherein the input configuration data is decrypted by performing a bitwise Exclusive-OR operation on the input configuration data using the values from the portion of the configuration memory.