Miscellaneous Control Module (MCM)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
Freescale Semiconductor
16-17
Preliminary
16.3
Functional Description
16.3.1
High-Priority Enables
The MCM contains an output to each core which are used with the AXBS-lite to elevate the priority of
interrupt service routine accesses in the system bus controllers’ arbitration schemes.
The core processors are configured to support critical and/or external interrupts. Furthermore, each
processor can be configured to employ priority elevation on critical and/or external interrupt events.
Critical interrupts come from outside the device and are routed directly to the processor’s critical interrupt
input. External interrupts are routed through the interrupt controller. In addition to the interrupt notification
signals, various processor-specific configuration flags from the processor’s machine check register
(MCR[ee,ce]) and the hardware implementation register (HID1) are sent to the 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 throughout the duration of
interrupt servicing. 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 throughout the duration of interrupt servicing.
Be careful when using the priority elevation as it can enable a master to starve the rest of the masters in
the system. Reference
Chapter 15, “Crossbar Switch (XBAR)
,” for information on priority elevation and
the Z1 and Z0 Core Reference Manual for information on the use of the interrupts.
Offset:
MCM_BAS 0x006C
Access: User read only
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
R
REDR
W
Reset
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R
REDR
W
Reset
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
Figure 16-15. RAM ECC Data (REDR) Register
Table 16-16. REDR Field Descriptions
Field
Description
REDR
RAM ECC Data Register. Contains the data associated with the faulting access of the last, properly-enabled RAM
ECC event. The register contains the data value taken directly from the data bus.