Semiconductor integrated circuit and power supply control method therefor

A power supply control method for a semiconductor integrated circuit, the semiconductor integrated circuit comprising:

• a plurality of processing circuits each including a notification unit which outputs a notification signal according to processing state of the own processing circuit;
• a plurality of power supply switch units which switch connection states, which each are either a connected or a disconnected state, between respective ones of the plurality of processing circuits and a power supply source;
• a power supply switch control circuit which is connected with the notification unit included in respective ones of the plurality of processing circuits, stores power supply control information including the connection states of respective ones of the power supply switch units and controls the connection states on the basis of the notification signals and the power supply control information;
• and
• data and address buses which connect each of the plurality of processing circuits with the power supply switch control circuit,
• wherein:
• the plurality of processing circuits include at least a memory circuit storing instruction code and data, and a process execution circuit for executing a process on the basis of the instruction code and data stored in the memory circuit;
• at least two or more of the plurality of processing circuits
• update the power supply control information via the data and address buses before the power supply switch connecting the updating processing circuit with the power supply source is turned off;
• and
• the power supply switch control circuit
• accepts a notification signal outputted from any one of the plurality of processing circuits after the update, and controls the connection states of respective ones of the plurality of power supply switch units on the basis of the updated power supply control information.