User Manual
BCM1250/BCM1125/BCM1125H
10/21/02
B r o a d c o m C o r p o r a t i o n
Document
1250_1125-UM100CB-R
Section 8: PCI Bus and HyperTransport Fabric Page
245
34
Reserved R/O 000000
Cap Ptr R/O
40
Points to HyperTransport capability registers.
38
ROM base address R/O 0
The HyperTransport bridge does not support an
expansion ROM.
3C
Bridge Ctrl (See
R/W 0000
Int Pin
R/O 0
Int line
R/O 0
RevId >= 3
R/W 0
The HyperTransport does not use the interrupt
registers, they always read as zero.
On interface revision 3 and later the Int Line register
is R/W but unused by the hardware as
recommended by the HT specification.
40
HTCmd (See
R/W 2001
Cap Ptr
R/O 00
Cap Id
R/O 08
This is the HyperTransport capability block, there
are no further blocks.
44
LinkConfig (See
R/O 0000
LinkCtrl (See
R/W 0000
As defined in the HyperTransport specification.
48
Reserved
R/O 0000
RevId >=3 LinkFreqCap
R/O 801F
LDT Freq
(
R/W 00
LDT Rev Id
R/O 11
RevId >=3
R/O 23
Interface revId 1 and 2 is based on HyperTransport
revision 0.17.
Interface revision 3 is based on HyperTransport
revision 1.03. The LinkFreqCap indicates operation
at 200-600MHz and vendor specific frequencies.
4C
Reserved
R/O Unpredictable
R/O 0000
Reserved
R/O Unpredictable
RevId >=3 Features
R/O 0004
Reserved on RevId 1 and 2.
On revision 3 and later, this is the feature register
indicating support for CRC test and not other
features.
50
SriCmd (See
R/W 0000
SriRxDen
R/W 10
SriTxDen
R/W 10
System Reset Initialization registers. These
registers must be configured by the CPU before the
HyperTransport fabric comes out of reset. The
interface will assert the LDT_RESET_L signal until
the SipReady bit in the SriCmd register is set to
indicate that these registers have been
programmed.
54
SriTxNumerator
R/W 0000FFFF
58
SriRxNumerator
R/W 0000FFFF
5C
Reserved R/O Unpredictable
RevId >=3 IsocBAR
R/W 00000000
Reserved on RevId 1 and 2.
On RevId 3 and later, the IsocBAR and
IsocIgnMask selects an address range that inbound
transactions will be allocated in the L2 cache.
See
Section: “Force Isochronous Mode Address
60
Reserved R/O Unpredictable
RevId >=3 IsocIgnMask
R/W 00000000
64
Reserved R/O Unpredictable
Reserved
68
ErrStatus
(
R/C 00
R/W 000000
Error control and status register. Provides
additional control over interface error reporting.
6C
Reserved
R/O 00
TxCtrl (See
R/W 04
DataBufAloc
(
R/W 1515
Control registers.
Table 140: HyperTransport Configuration Header (Type 1)
(Cont.)
Offset
Register Bits
Description
31
24
23
16
15
8
7
0