Vol. 3C 34-7

SYSTEM MANAGEMENT MODE

Table 34-3.  SMRAM State Save Map for Intel 64 Architecture

Offset 

(Added to SMBASE + 8000H)

Register

Writable?

7FF8H

CR0

No

7FF0H

CR3

No

7FE8H

RFLAGS

Yes

7FE0H

IA32_EFER

Yes

7FD8H

RIP

Yes

7FD0H

DR6

No

7FC8H

DR7

No

7FC4H

TR SEL

1

No

7FC0H

LDTR SEL

1

No

7FBCH

GS SEL

1

No

7FB8H

FS SEL

1

No

7FB4H

DS SEL

1

No

7FB0H

SS SEL

1

No

7FACH

CS SEL

1

No

7FA8H

ES SEL

1

No

7FA4H

IO_MISC

No

7F9CH

IO_MEM_ADDR

No

7F94H

RDI

Yes

7F8CH

RSI

Yes

7F84H

RBP

Yes

7F7CH

RSP

Yes

7F74H

RBX

Yes

7F6CH

RDX

Yes

7F64H

RCX

Yes

7F5CH

RAX

Yes

7F54H

R8

Yes

7F4CH

R9

Yes

7F44H

R10

Yes

7F3CH

R11

Yes

7F34H

R12

Yes

7F2CH

R13

Yes

7F24H

R14

Yes

7F1CH

R15

Yes

7F1BH-7F04H

Reserved

No

7F02H

Auto HALT Restart Field (Word) 

Yes

7F00H

I/O Instruction Restart Field (Word)

Yes

7EFCH

SMM Revision Identifier Field (Doubleword)

No

7EF8H

SMBASE Field (Doubleword)

Yes