307013-003 Datasheet, PDF (749/848 Pages) Intel Corporation – Intel I/O Controller Hub 7

Intel® High Definition Audio Controller Registers (D27:F0)
19.2.34 DPLBASE—DMA Position Lower Base Address Register
(Intel^® High Definition Audio Controller—D27:F0)
Memory Address:HDBAR + 70h
Default Value: 00000000h
Attribute:
Size:
R/W, RO
32 bits
Bit
Description
31:7
6:1
0
DMA Position Lower Base Address — R/W. Lower 32 bits of the DMA Position Buffer
Base Address. This register field must not be written when any DMA engine is running
or the DMA transfer may be corrupted. This same address is used by the Flush Control
and must be programmed with a valid value before the Flush Control bit
(HDBAR+08h:bit 1) is set.
DMA Position Lower Base Unimplemented bits — RO. Hardwired to 0 to force the 128-
byte buffer alignment for cache line write optimizations.
DMA Position Buffer Enable — R/W.
0 = Disable.
1 = Enable. The controller will write the DMA positions of each of the DMA engines to
the buffer in the main memory periodically (typically once per frame). Software can
use this value to dtermine what data in memory is valid data.
19.2.35 DPUBASE—DMA Position Upper Base Address Register
(Intel^® High Definition Audio Controller—D27:F0)
Memory Address:HDBAR + 74h
Default Value: 00000000h
Attribute:
Size:
R/W
32 bits
Bit
Description
31:0
DMA Position Upper Base Address — R/W. Upper 32 bits of the DMA Position Buffer
Base Address. This register field must not be written when any DMA engine is running
or the DMA transfer may be corrupted.
Intel ^® ICH7 Family Datasheet
749