Texas Instruments OMAP5912 Reference Manual page 979

Layer 4 Interconnect
28 Peripheral Interconnects
To perform an MPU access, the MPU software must first set (write 1) the
MPU SWITCH bit in the SSW_MPU_CONF register. Then all the MPU TIPB
_
bus signals are connected either to the TIPB bus peripheral signals (for a TIPB
peripheral), or to the dedicated wrapper TIPB bus interface (for OCP
peripheral).
To perform a DSP access, the MPU software must first authorize this access
by resetting the MPU SWITCH bit in the SSW_MPU_CONF register (write 0);
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then the DSP software must set the DSP
register.
If the MPU wants to access the SSW
DSP_SWITCH bit is set, the access is completed but a write access has no
effect on the register.
Symmetrically, if the DSP wants to access the SSW_DSP_CONF register
when the MPU SWITCH bit is set, the access is completed but a write access
_
has no effect on the register.
The following programming sequence enables DSP access to the peripheral:
1) Check that the MPU
the same peripheral).
2) Set the DSP SWITCH bit in the SSW
_
write 1)
3) Check that the DSP
MPU software).
4) Perform the shared peripheral access through the DSP TIPB bus.
5) After the completion of this access, reset the DSP
SSW DSP CONF register (write 0).
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The following programming sequence enables MPU access to the peripheral:
6) Check that DSP_SWITCH bit is reset (no DSP access is on going on the
same peripheral).
7) Set the MPU SWITCH bit in the SSW
_
software: write 1).
8) Check that the MPU
DSP software).
9) Perform the shared peripheral access through the MPU TIPB bus.
10) After the completion of this access, reset the MPU
SSW MPU CONF register (write 0)
_ _
SWITCH in the SSW_DSP_CONF
_
MPU
_
SWITCH bit is reset (no MPU access is ongoing on
_
DSP
_ _
SWITCH is set (in case of priority conflict with the
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SWITCH is set (in case of priority conflict with the
_
CONF
register when the
_
CONF register (DSP software:
SWITCH bit in the
_
MPU CONF register (MPU
_ _
SWITCH bit in the
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SPRU758A