CRITICALITY

Low

DESCRIPTION

Issue is seen to come when there is need to place the DSP subsystem to a low power state.

The DSP requires the internal emulation clock to be actively toggling in order to successfully enter a low power mode via execution of the IDLE instruction and PRCM MStandby/Idle handshake. This assumes that other prerequisites and software sequence are followed.

WORKAROUND

The CD_EMU domain can be set in SW_WKUP mode via the CM_EMU_CLKSTCTRL[1:0] CLKTRCTRL field.

The emulation clock to the DSP is free-running anytime CCS is connected via JTAG debugger to the DSP subsystem or when the CD_EMU clock domain is set in SW_WKUP mode.

Note: If it is sure that the DSP would never enter any low power state (in other words the DSP would never execute IDLE instruction), the workaround can be ignored.

REVISIONS IMPACTED

SR 2.0, 1.1, 1.0

TDA2x: 2.0, 1.1, 1.0

DRA75x, DRA74x: 2.0, 1.1, 1.0

AM572x: 2.0, 1.1