Raven Interrupt Controller Implementation
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2
Operation
Interprocessor Interrupts
Four interprocessor interrupt (IPI) channels are provided for use by all
processors. During system initialization the IPI vector/priority registers for
each channel should be programmed to set the priority and vector returned
for each IPI event. During system operation a processor may generate an
IPI by writing a destination mask to one of the IPI dispatch registers.
Note that each IPI dispatch register is shared by both processors. Each IPI
dispatch register has two addresses but they are shared by both processors.
That is, there is a total of four IPI dispatch registers in the RavenMPIC.
The IPI mechanism may be used for self interrupts by programming the
dispatch register with the bit mask for the originating processor.
Dynamically Changing I/O Interrupt Configuration
The interrupt controller provides a mechanism for safely changing the
vector, priority, or destination of I/O interrupt sources. This is provided to
support systems which allow dynamic configuration of I/O devices. In
order to change the vector, priority, or destination of an active interrupt
source, the following sequence should be performed:
1. Mask the source using the MASK bit in the vector/priority register.
2. Wait for the activity bit (ACT) for that source to be cleared.
3. Make the desired changes.
4. Unmask the source.
This sequence ensures that the vector, priority, destination, and mask
information remain valid until all processing of pending interrupts is
complete.
EOI Register
Each processor has a private EOI register which is used to signal the end
of processing for a particular interrupt event. If multiple nested interrupts
are in service, the EOI command terminates the interrupt service of the
Summary of Contents for MVME2700 Series
Page 1: ...MVME2600 2700 Series Single Board Computer Programmer s Reference Guide V2600A PG2 ...
Page 13: ...xiv ...
Page 15: ...xvi ...
Page 67: ...1 50 Board Description and Memory Maps 1 ...
Page 151: ...2 84 Raven PCI Host Bridge Multi Processor Interrupt Controller Chip 2 ...
Page 215: ...3 64 Falcon ECC Memory Controller Chip Set 3 ...
Page 277: ...Glossary GL 14 G L O S S A R Y ...