Memory Protection Unit (MPU)
MPC5510 Microcontroller Family Reference Manual, Rev. 1
Freescale Semiconductor
17-7
Preliminary
17.3.2.3
MPU Error Detail Register, MPU Port 0 to 2 (MPU_EDRn)
When the MPU detects an access error on MPU port
n
, 32 bits of error detail are captured in this read-only
register and the corresponding bit in the MPU_CESR[MPERR] field set. Information on the faulting
address is captured in the corresponding MPU_EAR
n
register at the same time. A read of the MPU_EDR
n
register clears the corresponding bit in the MPU_CESR[MPERR] field.
17.3.2.4
MPU Region Descriptor n (MPU_RGDn)
Each 128-bit (16 byte) region descriptor specifies a given memory space and the access attributes
associated with that space. The descriptor definition is fundamental to the operation of the MPU.
Offset: MP 0x00014 (MPU_EDR0)
MP 0x001C (MPU_EDR1)
MP 0x0024 (MPU_EDR2)
Access: User read only
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
R
EACD
EPID
EMN
EATTR
E
R
W
W
Reset –
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
Figure 17-4. MPU Error Detail Register, Slave Port n (MPU_EDRn)
Table 17-4. MPU_EDRn Field Descriptions
Field
Description
EACD
Error Access Control Detail. This 16-bit read-only field implements one bit per region descriptor and is an indication
of the region descriptor hit logically-ANDed with the access error indication. The MPU performs a
reference-by-reference evaluation to determine the presence/absence of an access error. When an error is detected,
the hit-qualified access control vector is captured in this field.
If the MPU_EDRn register contains a captured error and the EACD field is all zeroes, this signals an access that did
not hit in any region descriptor. All non-zero EACD values signal references that hit in a region descriptor(s), but failed
due to a protection error as defined by the specific set bits.
EPID
Error Process Identification. This 8-bit read-only field records the process identifier of the faulting reference. The
process identifier is typically driven by processor cores only; for other bus masters, this field is cleared.
EMN
Error Master Number. This 4-bit read-only field records the logical master number of the faulting reference. This field
is used to determine the bus master that generated the access error.
EATTR
Error Attributes. This 3-bit read-only field records attribute information about the faulting reference. The supported
encodings are defined as:
000 User mode, instruction access
001 User mode, data access
010 Supervisor mode, instruction access
011 Supervisor mode, data access
All other encodings are reserved. For non-core bus masters, the access attribute information is typically wired to
supervisor, data (0b011).
ERW
Error Read/Write. This 1-bit read-only field signals the access type (read, write) of the faulting reference.
0 Read
1 Write