E-16
MPC8240 Integrated Processor User’s Manual
PowerPC Register Set
Figure E-12. Upper BAT Register
Figure E-13. Lower BAT Register
Table E-10 describes the bits in the BAT registers.
Table E-10. BAT Registers—Field and Bit Descriptions
Upper/Lower
BAT
Bits
Name
Description
Upper BAT
Register
0–14
BEPI
Block effective page index. This field is compared with high-order bits of the
logical address to determine if there is a hit in that BAT array entry.
15–18
—
Reserved
19–29
BL
Block length. BL is a mask that encodes the size of the block. Values for
this field are listed in Table E-11.
30
Vs
Supervisor mode valid bit. This bit interacts with MSR[PR] to determine if
there is a match with the logical address.
31
Vp
User mode valid bit. This bit also interacts with MSR[PR] to determine if
there is a match with the logical address.
Lower BAT
Register
0–14
BRPN
This field is used in conjunction with the BL field to generate high-order bits
of the physical address of the block.
15–24
—
Reserved
25–28
WIMG
Memory/cache access mode bits
W Write-through
I
Caching-inhibited
M Memory coherence
G Guarded
Attempting to write to the W and G bits in IBAT registers causes
boundedly-undefined results.
29
—
Reserved
30–31
PP
Protection bits for block. This field determines the protection for the block.
BEPI
0 000
BL
Vs Vp
0
14 15
18 19
29 30 31
Reserved
Reserved
0
14 15
24 25
28 29 30
31
BRPN
0 0000 0000 0
WIMG*
0
PP
*W and G bits are not defined for IBAT registers. Attempting to write to these bits causes boundedly-undefined results.
Содержание MPC8240
Страница 1: ...MPC8240UM D Rev 1 1 2001 MPC8240 Integrated Processor User s Manual ...
Страница 38: ...xviii MPC8240 Integrated Processor User s Manual TABLES Table Number Title Page Number ...
Страница 48: ...xlviii MPC8240 Integrated Processor User s Manual Acronyms and Abbreviations ...
Страница 312: ...6 94 MPC8240 Integrated Processor User s Manual ROM Flash Interface Operation ...
Страница 348: ...7 36 MPC8240 Integrated Processor User s Manual PCI Host and Agent Modes ...
Страница 372: ...8 24 MPC8240 Integrated Processor User s Manual DMA Register Descriptions ...
Страница 394: ...9 22 MPC8240 Integrated Processor User s Manual I2O Interface ...
Страница 412: ...10 18 MPC8240 Integrated Processor User s Manual Programming Guidelines ...
Страница 454: ...12 14 MPC8240 Integrated Processor User s Manual Internal Arbitration ...
Страница 466: ...13 12 MPC8240 Integrated Processor User s Manual Exception Latencies ...
Страница 516: ...16 14 Watchpoint Trigger Applications ...
Страница 538: ...B 16 MPC8240 Integrated Processor User s Manual Setting the Endian Mode of Operation ...
Страница 546: ...C 8 MPC8240 Integrated Processor User s Manual ...
Страница 640: ...INDEX Index 16 MPC8240 Integrated Processor User s Manual ...