MPU Memory Management Unit
2-44
Figure 2–20. Sequence for Checking Faults
Virtual address
Page
domain
fault
No access (D0)
Reserved (10)
Section
domain
fault
Alignment
fault
Misaligned
Page
translation
fault
Invalid
Section
transistor
fault
Section
Get level 1 descriptor
Page
Check address alignment
Invalid
Manager (0.1)
Client (0.1)
Check domain status
Check access
permissions
Violation
Section
permission
fault
Physical address
No access (D0)
Reserved (10)
Section
Page
Client (0.1)
Violation
Subpage
permission
fault
Check access
permissions
Get page
table entry
2.7.11.1
Alignment Fault
If an alignment fault is enabled (bit 1 in CP15 control register 1), the MMU gen-
erates an alignment fault upon 16-bit and 32-bit data accesses that are
improperly aligned (not on an address multiple of 2 and 4, respectively). The
TI925T checks the alignment even if the MMU is disabled.
Instruction fetches do not generate alignment faults; they always access
memory on 32-bit word boundaries.