Processor Configuration Registers
58
Datasheet, Volume 2
7:3
RW-L
05h
Uncore
Graphics Mode Select (GMS)
This field is used to select the amount of main memory that is pre-
allocated to support the Internal Graphics device in VGA (non-
linear) and Native (linear) modes. BIOS ensures that memory is
pre-allocated only when internal graphics is enabled.
This register is also Intel TXT lockable.
Hardware does not clear or set any of these bits automatically
based on IGD being disabled/enabled.
BIOS Requirement:
BIOS must not set this field to 0h if IVD (bit
1 of this register) is 0.
0h = 0 MB
1h = 32 MB
2h = 64 MB
3h = 96 MB
4h = 128 MB
5h = 160 MB
6h = 192 MB
7h = 224 MB
8h = 256 MB
9h = 288 MB
Ah = 320 MB
Bh = 352 MB
Ch = 384 MB
Dh = 416 MB
Eh = 448MB
Fh = 480 MB
10h = 512 MB
Other = Reserved
2
RO
0h
Reserved
1
RW-L
0b
Uncore
IGD VGA Disable (IVD)
0 = Enable. Device 2 (IGD) claims VGA memory and I/O cycles,
the Sub-Class Code within Device 2 Class Code register is 00.
1 = Disable. Device 2 (IGD) does not claim VGA cycles (Memory
and I/O), and the Sub- Class Code field within Device 2
function 0 Class Code register is 80h.
BIOS Requirement:
BIOS must not set this bit to 0 if the GMS
field (bits 7:3 of this register) pre-allocates no memory.
This bit MUST be set to 1 if Device 2 is disabled using a register
(DEVEN[3] = 0).
This register is locked by Intel TXT lock.
0
RW-KL
0b
Uncore
GGC Lock (GGCLCK)
When set to 1b, this bit will lock all bits in this register.
B/D/F/Type:
0/0/0/PCI
Address Offset:
50–51h
Reset Value:
0028h
Access:
RW-KL, RW-L
Size:
16 bits
BIOS Optimal Default
00h
Bit
Attr
Reset
Value
RST/
PWR
Description
Содержание 2ND GENERATION CORE PROCESSOR FAMILY DESKTOP - VOLUME 2 01-2011
Страница 12: ...Introduction 12 Datasheet Volume 2...