Texas Instruments OMAP5912 Reference Manual page 335

DSP Memory Management Unit
Figure 22. DSP Memory Request Results Example
Page Fault
Table walker
enabled
Stall DSP Stall DSP, generate MPU
HW table walker interrupt
MPU handles fault
fetches descriptor
TLB updated updating TLB
DSP released MPU acknowledges fault
MMU releases DSP
OR MPU resets DSP
7.3.2 Lock Mechanism and the Current_Victim Counter
72 DSP Subsystem
DSP External access (or 1
TLB miss
Table walker
disabled
Stall DSP, generate MPU interrupt
MPU handles fault, updating TLB
MPU acknowledges fault
MMU releases DSP
OR MPU resets DSP
Any TLB entry can be locked, but 31 entries is the maximum number that can
be locked. The lock mechanism prevents an entry of the TLB from being
replaced by another entry when a TLB miss occurs. If the Base_Value field of
LOCK_REG is > 0, TLB entries from Base_value − 1 down to 0 are locked.
Frequently used memory areas or memory areas used by applications with
critical real-time constraints must be loaded in these locations and the
base_value counter must be set accordingly.
The current_victim counter of the LOCK_REG register specifies the location
of the entry, which is loaded or replaced.
A TLB miss fault does not occur if the hardware table is enabled. All TLB
entries can not be locked (a maximum of 31 entries can be locked).
st
access of a burst)
TLB hit
Check permission
Invalid
Permission fault
Valid
Memory access
DSP continue
execution
SPRU750A