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Interrupt Controller Modules
17-8
Freescale Semiconductor
17.2.5
Set Interrupt Mask Register (SIMR
n
)
The SIMR
n
register provides a simple mechanism to set a given bit in the IMR
n
registers to mask the
corresponding interrupt request. The value written to the SIMR field causes the corresponding bit in the
IMR
n
register to be set. The SIMR
n
[SALL] bit provides a global set function, forcing the entire contents
of IMR
n
to be set, thus masking all interrupts. Reads of this register return all zeroes. This register is
provided so interrupt service routines can easily mask the given interrupt request without the need to
perform a read-modify-write sequence on the IMR
n
register.
Table 17-9. ICONFIG Field Descriptions
Field
Description
15–9
ELVLPRI
Enable core’s priority elevation on priority levels. Each ELVLPRI[7:1] bit corresponds to the available priority
levels 1 – 7. If set, the assertion of the corresponding level-
n
request to the core causes the processor’s bus
master priority to be temporarily elevated in the device’s crossbar switch arbitration logic. The processor’s bus
master arbitration priority remains elevated until the level-
n
request is negated. If round-robin arbitration is
enabled, this bit has no effect.
If cleared, the assertion of a level-n request does not affect the processor’s bus master priority.
8–6
Reserved, must be cleared.
5
EMASK
If set, the interrupt controller automatically loads the level of an interrupt request into the CLMASK (current level
mask) when the acknowledge is performed. At the exact same cycle, the value of the current interrupt level mask is
saved in the SLMASK (saved level mask) register.
This feature can be used to support software-managed nested interrupts, and is intended to complement the
interrupt masking functions supported in the ColdFire processor. The value of SLMASK register should be read from
the interrupt controller and saved in the interrupt stack frame in memory, and restored near the service routine’s exit.
If cleared, the INTC does not perform any automatic masking of interrupt levels. The state of this bit does not affect
the ColdFire processor’s interrupt masking logic in any manner.
4–0
Reserved, must be cleared.
Address: 0xFC04_801C (SIMR0)
0xFC04_C01C (SIMR1)
Access: User write-only
7
6
5
4
3
2
1
0
R
0
0
0
0
0
0
0
0
W
SALL
SIMR
Reset:
0
0
0
0
0
0
0
0
Figure 17-8. Set Interrupt Mask Register (SIMR
n
)
Table 17-10. SIMR
n
Field Descriptions
Field
Description
7
Reserved, must be cleared.
6
SALL
Set all bits in the IMR
n
register, masking all interrupt requests.
0 Only set those bits specified in the SIMR field.
1 Set all bits in IMR
n
register. The SIMR field is ignored.
5–0
SIMR
Set the corresponding bit in the IMR
n
register, masking the interrupt request.
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...