[#4313] System with EMAC driver enabled - Core not idling
Submitted By: Michael Hennerich
2008-08-06 04:29:44 Close Date
Closed Fixed In Release:
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BF537 Silicon Revision:
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Summary: System with EMAC driver enabled - Core not idling
BF537/6 using EMAC consumes approx. twice the internal power during idle.
This is caused by the system never really going into idle.
By default we enabled all bits in the SIC_IWR register, thus every activated Peripheral signaling an Interrupt to the SIC may wake up the core while in idle state.
Usually its part of the peripherals control/initialization whether they should signal an IRQ to the SIC or not.
This applies for all peripherals except for the EMAC.
None of the Bits in EMAC_TX_IRQE are set, and also DMA2 (TX) is set up without interrupts.
And still we see MAC TX constantly latched in SIC_ISR – thus causing a constant assertion of Awake from idle.
--- Michael Hennerich 2008-08-06 05:59:12
Fixed on 2008R1 and svn trunk.
Disable all bits in SIC_IWR unless we are going into a real (DPMC) power saving
mode. Any Interrupt can wake the core form it’s idle; state.
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