AMD SB600 - Manual (Page 220)

©2008 Advanced Micro Devices, Inc. AC ’97 Controller Functional Descriptions
AMD SB600 Register Reference Manual Proprietary Page 220
Modem Command - RW - 32 bits - [MEM_Reg: 08h]
Field Name Bits Default Description
Modem send out through
DMA2 enable 3 0b Enables sending of modem data to slot 10 on AC link
using out DMA2
Modem send out through
DMA3 enable 4 0b Enables sending of modem data to slot 11 on AC link
using out DMA3
Status To Mem 5 0b When reg0x04[1] is enabled, after finishing an input or
output modem DT data block, the status will be
updated in either DT memory or in reg0x00.
0: Update status to register
1: Update status to memory
Modem_slots_alloc_1 6 0h Refer to Modem_slots_alloc_0 (bit 27 of this register)
for more detailed information.
Reserved 7 0h
In DMA enable 8 0b Enables input DMA
Out DMA #1 enable 9 0b Enables output DMA 1
Out DMA #2 enable 10 0b Enables output DMA 2
Out DMA #3 enable 11 0b Enables output DMA 3
Reserved 19:12 00h
Audio present 20 0b 1 - Audio is present;
0 - Audio is not present (for Modem driver), set by
BIOS [Read-only]
Reserved 21 0b
Gpio through DMA en 22 0b 1 - Gpio data (slot 12) comes from DMA 3 along with
data for slot 11.
0 - Gpio data (slot 12) comes from Gpio register 74h.
Loop back enable 23 0b Enables loop-back mode. The SDATA_OUT
connected directly to the SDATA_IN
Packed format disable 24 0b 1 - Disable packed format for sending data: data is
sent to memory including data from Slot1 and 2
(physical address and data are sent to memory along
with other data).
0 - Data sent to memory through DMA in packed
format, no slot 1 and 2 - default
Burst enable. 25 0b Enables Burst operation: Will send/request data only
based on threshold value & overflow condition.
Panic enable 26 0b Enables panic signal - to get more priority over internal
bus.
Modem_slots_alloc_0 27 0b Once this bit is set to 1, writing 0 to it has no effect.
{Modem_slots_alloc_1, Modem_slots_alloc_0} =
00: Only slot 5 is allocated to the modem.
01: Slots 5 and 12 are allocated to the modem.
10: Slots 5, 10, 11, and 12 are allocated to the
modem.
11: Slots 5, 10, 11, and 12 are allocated to the
modem.
AC Link active 28 0b 1 - AC Link is in the ACTIVE state.;
0 - AC Link is not in the ACTIVE state. [Read-only]
AC'97 software reset 29 0b 0 – De-assert ac97 software reset asynchronous to
BIT_CLK
1 – Assert ac97software reset asynchronous to
BIT_CLK. Registers in BIT_CLK domain will be reset.
AC97 Sync 30 0b 0 – De-assert AC link’s SYNC asynchronous to
BIT_CLK
1 – Assert AC link’s SYNC asynchronous to BIT_CLK
AC97 Reset# 31 0b 1 – De-assert AC link’s RESET# asynchronous to
BIT_CLK
0 – Assert AC link’s RESET# asynchronous to
BIT_CLK