The next stage of INTC is to enable interrupts based on programmed settings. The following sequence has to be followed to enable interrupts:
- Enable required interrupts: System interrupts
that are required to get propagated to host are to
be enabled individually by writing to [9-0]
ENABLE_SET_INDEX bit field in the interrupt enable
indexed set register
(ICSS_INTC_ENABLE_SET_INDEX_REG). The interrupt to
enable is the index value written. This sets the
Enable Register bit of the given index.
- Enable required host interrupts: By writing 1h to
the appropriate bit of the [9-0]
HINT_ENABLE_SET_INDEX bit field in the host
interrupt enable indexed set register
(ICSS_INTC_HINT_ENABLE_SET_INDEX_REG), enable the
required host interrupts. The host interrupt to
enable is the index value written. This enables
the host interrupt output or triggers the output
again if that host interrupt is already
enabled.
- Enable all host interrupts: By setting the [0]
ENABLE_HINT_ANY bit in the global enable register
(ICSS_INTC_GLOBAL_ENABLE_HINT_REG) to 1h, all host
interrupts will be enabled. Individual host
interrupts are still enabled or disabled from
their individual enables and are not overridden by
the global enable.