IBM SA14-2339-04 Personal Computer User Manual


 
9-184 PPC405 Core User’s Manual
tlbre
TLB Read Entry
tlbre
TLB Read Entry
if WS
4
= 1
(RT)
TLBLO[(RA
26:31
)]
else
(RT)
TLBHI[(RA
26:31
)]
(PID)
TID from TLB[(RA
26:31
)]
The contents of the selected TLB entry is placed into register RT (and possibly into PID).
Bits 26:31 of the contents of RA is used as an index into the TLB. If this index specifies a TLB entry
that does not exist, the results are undefined.
The WS field specifies which portion (TLBHI or TLBLO) of the entry is loaded into RT. If TLBHI is
being accessed, the PID SPR is set to the value of the TID field in the TLB entry.
If the WS field is not 0 or 1, the instruction form is invalid and the result is undefined.
If instruction bit 31 contains 1, the contents of CR[CR0] are undefined.
Registers Altered
•RT
PID (if
WS = 0)
Invalid Instruction Forms
Reserved fields
Invalid WS value
Programming Notes
This instruction is privileged. Translation is not required to be active during the execution of this
instruction.
The contents of RT after the execution of this instruction are interpreted as follows:
If WS = 0 (TLBHI):
RT[0:21] EPN[0:21]
RT[22:24] SIZE[0:2]
RT[25] V
RT[26] E
RT[27] U0
RT[28:31] 0
PID[24:31] TID[0:7]; (note that the TID is copied to the PID, not to RT)
If WS = 1 (TLBLO):
RT[0:21] RPN[0:21]
RT[22:23] EX,WR
RT[24:27] ZSEL[0:3]
RT[28:31] WIMG
tlbre RT, RA, WS
31 RT RA WS 946
0 6 11 16 21 31