Interrupts
MPC5510 Microcontroller Family Reference Manual, Rev. 1
8-20
Freescale Semiconductor
Preliminary
Figure 8-5. NMI Connections
8.4.4
Dynamic Priority Elevation
Zen Core processors support critical and external interrupts. Each processor can be configured to employ
priority elevation on critical and/or external interrupt events. Critical interrupts come from external pins
PD10 or PD11 or the SoftMLB interface logic, and are routed to the processor’s critical interrupt input.
External interrupts come from the peripherals and are routed through the interrupt controller. In addition
to the interrupt notification signals, various processor specific configuration flags from the Zen processor’s
Machine Check Register (MCR[ee,ce]) and the Hardware Implementation register (HID1) are sent to the
Miscellaneous Control Module (MCM) to determine when interrupt servicing is enabled and when
high-priority elevation should be enabled. If the corresponding processor is configured to allow
high-priority elevation on critical interrupt events, the MCM generates the high-priority signal upon
critical interrupt detection and holds it active for the duration of interrupt servicing until a return from
critical interrupt (rfci) is detected. If the corresponding processor is configured to allow high-priority
elevation on external interrupt events, the MCM generates the high-priority signal upon external interrupt
detection and holds it active for the duration of interrupt servicing, until a return from interrupt (rfi) is
detected.
Great care must be taken when using the priority elevation as it can enable a master to starve the rest of
the masters in the system.
8.4.4.1
Hardware Implementation Dependent Register 1
The HID1 register is used for bus configuration and system control. HID1 is shown in
.
•
•
•
•
Interrupt
controller
DMA/Interrupt S
e
lect
EIF0
EIF1
EIF2
EIF3
EIF4
EIF15
IMUX
Interrupt
request
DMA
request
eDMA
OVF0
OVF1
OVF15
SIU_OSR
SIU_EISR
External
IRQ pins or
internal
sources
•
•
•
•
•
SIU_DIRSR
SIU
NMI1
NMI0
PD11
PD10
•
•
•
Secondary
CPU
Primary
CPU
•
•
Overrun
request
Critical
interrupt
EIF5–EIF15
DIRS1
DIRS2
DIRS3
DIRS4
DIRS1
DIRS2
DIRS3
DIRS4
DIRS1
DIRS2
DIRS3
DIRS4