AC82G41SLGQ3 Datasheet, PDF (67/604 Pages) Intel Corporation – Intel® 4 Series Chipset Family

System Address Map
3.4.1
3.4.2
3.5
Memory Re-claim Background
The following are examples of Memory Mapped IO devices are typically located below
4 GB:
• High BIOS
• HSEG
• TSEG
• GFX stolen
• GTT stolen
• XAPIC
• Local APIC
• FSB Interrupts
• Mbase/Mlimit
• Memory Mapped I/O space that supports only 32-bit addressing
The (G)MCH provides the capability to re-claim the physical memory overlapped by the
Memory Mapped I/O logical address space. The (G)MCH re-maps physical memory
from the Top of Low Memory (TOLUD) boundary up to the 4 GB boundary to an
equivalent sized logical address range located just below the Intel ME's stolen memory.
Memory Reclaiming
An incoming address (referred to as a logical address) is checked to see if it falls in the
memory re-map window. The bottom of the re-map window is defined by the value in
the RECLAIMBASE register. The top of the re-map window is defined by the value in the
RECLAIMLIMIT register. An address that falls within this window is reclaimed to the
physical memory starting at the address defined by the TOLUD register. The TOLUD
register must be 64 MB aligned when RECLAIM is enabled, but can be 1 MB aligned
when reclaim is disabled.
PCI Express* Configuration Address Space
There is a device 0 register, PCIEXBAR, which defines the base address for the
configuration space associated with all devices and functions that are potentially a part
of the PCI Express root complex hierarchy. The size of this range will be programmable
for the (G)MCH. BIOS must assign this address range such that it will not conflict with
any other address ranges.
Datasheet
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