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DSP Reset
10.4 DSP Reset
Note: The effects of DSP local reset and DSP module reset have not been fully validated; therefore, these resets are not supported and should not be used. Instead, the POR or RESET pins should be used to reset the entire DSP.
With access to the power and sleep controller (PSC) registers, the external host (for example, PCI or HPI) can assert and
10.4.1 DSP Local Reset
The following steps describe how an external host can
1.Clear the LRST bit in MDCTL39 to 0 to assert DSP reset.
2.Set the LRST bit in MDCTL39 to 1 to
10.4.2DSP Module Reset
The external host may program the PSC to assert DSP module reset by placing the DSP in either Software Reset Disable (SwRstDisable) state or Synchronous Reset (SyncReset) state. See Chapter 6 for descriptions of these PSC states.
10.4.2.1 Software Reset Disable (SwRstDisable)
In the software reset disable (SwRstDisable) state, the DSP’s module reset is asserted and its module clock is turned off. You can use this state to reset the DSP. The following steps describe how to put the DSP in the software reset disable state:
∙Host: Notify the DSP to prepare for
∙DSP: Put the DSP in the IDLE state.
–Set PDCCMD to 0001 5555h. PDCMD is a control register in the DSP
Note: This register can only be written while the DSP is in its supervisor mode.
–Execute the IDLE instruction if the DSP is in the enable state. IDLE is a program instruction in the C64x+ CPU instruction set. When the CPU executes IDLE, the PDC is notified and will initiate the DSP
∙Host: Software reset disable DSP.
–Wait for the GOSTAT[0] bit in PTSTAT to clear to 0. You must wait for the power domain to finish any previously initiated transitions before initiating a new transition.
–Clear the NEXT bit in MDCTL39 to 0 to prepare the DSP module for a SwRstDisable transition.
–Set the GO[0] bit in PTCMD to 1 to initiate the state transition.
–Wait for GOSTAT[0] bit in PTSTAT to clear to 0. The module is safely in the new state only after the GOSTAT[0] bit is cleared to 0.
Reset | 93 |