Fujitsu Fujitsu SPARC64 V manual Reset, REDstate, and errorstate, Reset Types, Power-on Reset POR

Models: Fujitsu SPARC64 V

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F. APPENDIX O

Reset, RED_state, and error_state

The appendix contains these sections:

Reset Types on page 137

RED_state and error_state on page 139

Processor State after Reset and in RED_state on page 141

O.1 Reset Types

This section describes the four reset types: power-on reset, watchdog reset, externally initiated reset, and software-initiated reset.

O.1.1 Power-on Reset (POR)

For execution of the power-on reset on SPARC64 V, an external facility must issue the required sequence of JTAG commands to the processor.

While the UPA_RESET_L pin is asserted (low) or the Power ready signal is deasserted, the processor stops and executes only the specified JTAG command. The processor does not change any software-visible resources in the processor except the change by JTAG command execution and does not change any memory system state.

The sequence for the two types of power-on reset in SPARC64 V—hard power-on reset and soft power-on reset—is described below.

1.The UPA_RESET_L pin is asserted (low). The processor stops.

2.The external facility issues the required sequence of the JTAG commands. A different command sequence is required for hard power-on reset and soft power- on reset. The external facility decides the POR reset type to be executed.

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Page 148
Image 148
Fujitsu Fujitsu SPARC64 V manual Reset, REDstate, and errorstate, Reset Types, Power-on Reset POR