82NM10 Datasheet, PDF (608/671 Pages) Intel Corporation – Intel® NM10 Family Express Chipset

Intel HD Audio Controller Registers (D27:F0)
18.2.23 RIRBLBASE—RIRB Lower Base Address Register
(Intel HD Audio Controller—D27:F0)
Memory Address:HDBAR + 50h
Attribute:
R/W, RO
Default Value:
00000000hSize:32 bits
Bit
Description
31:7
6:0
RIRB Lower Base Address — R/W. This field is the lower address of the Response
Input Ring Buffer, allowing the RIRB base address to be assigned on any 128-B
boundary. This register field must not be written when the DMA engine is running or the
DMA transfer may be corrupted.
RIRB Lower Base Unimplemented Bits — RO. Hardwired to 0. This required the RIRB to
be allocated with 128-B granularity to allow for cache line fetch optimizations.
18.2.24 RIRBUBASE—RIRB Upper Base Address Register
(Intel HD Audio Controller—D27:F0)
Memory Address:HDBAR + 54h
Attribute:
R/W
Default Value:
00000000hSize:32 bits
Bit
Description
31:0
RIRB Upper Base Address — R/W. This field is the upper 32 bits of the address of the
Response Input Ring Buffer. This register field must not be written when the DMA
engine is running or the DMA transfer may be corrupted.
18.2.25 RIRBWP—RIRB Write Pointer Register
(Intel HD Audio Controller—D27:F0)
Memory Address:HDBAR + 58h
Attribute:
R/W, RO
Default Value:
0000hSize:16 bits
Bit
Description
15
14:8
7:0
RIRB Write Pointer Reset — R/W. Software writes a 1 to this bit to reset the RIRB
Write Pointer to 0. The RIRB DMA engine must be stopped prior to resetting the Write
Pointer or else DMA transfer may be corrupted.
This bit is always read as 0.
Reserved.
RIRB Write Pointer (RIRBWP) — RO. This field is the indicates the last valid RIRB
entry written by the DMA controller. Software reads this field to determine how many
responses it can read from the RIRB. The value read indicates the RIRB Write Pointer
offset in 2 DWord RIRB entry units (since each RIRB entry is 2 DWords long). Supports
up to 256 RIRB entries (256 x 8 B = 2 KB). This register field may be written when the
DMA engine is running.
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Datasheet