Product specifications

CN333 Data Sheet
Revision 1.0, January 5, 2005 -60- Device 0 Function 7 Register Descriptions – V-Link
Device 0 Function 7 Device-Specific Registers
These registers are normally programmed once at system
initialization time.
V-Link Control
Offset 40 – V-Link Specification ID (40h)........................RO
7-0 Specification Revision...................... always reads 40
Offset 41 – NB V-Link Capability (39h)...........................RO
7-6 Reserved ........................................ always reads 0
5 16-bit Bus Width Supported by NB ...................RO
0 Not Supported
1 Supported..............................................default
4 8-Bit Bus Width Supported by NB.....................RO
0 Not Supported
1 Supported..............................................default
3 4x Rate Supported by NB....................................RO
0 Not Supported
1 Supported..............................................default
2 2x Rate Supported by NB....................................RO
0 Not Supported ........................................default
1 Supported
1 Reserved ........................................ always reads 0
0 8x Rate Supported by NB....................................RO
0 Not Supported
1 Supported..............................................default
Offset 42 – NB Downlink Command (88h) .....................RW
7-4 DnCmd Max Request Depth (0=1 DnCmd).. def = 8
3-0 DnCmd Write Buffer Size (doublewords)..... def = 8
Offset 43 – NB Uplink Max Req Depth (80h) ..................RO
7-4 UpCmd Max Request Depth (0=1 UpCmd).. def = 8
Indicates the maximum allowable number of
outstanding UPCMD requests
3-0 Reserved ........................................ always reads 0
Offset 44 – NB Uplink Buffer Size (82h) ..........................RO
7-4 UpCmd P2C Write Buffer Size (max lines).. def = 8
3-0 UpCmd P2P Write Buffer Size (max lines) .. def = 2
Offset 45 –NB V-Link Bus Timer (44h).......................... RW
7-4 Timer for Normal Priority Requests from SB
0000 Immediate
0001 1*4 VCLKs
0010 2*4 VCLKs
0011 3*4 VCLKs
0100 4*4 VCLKs............................................ default
0101 5*4 VCLKs
0110 6*4 VCLKs
0111 7*4 VCLKs
1000 8*4 VCLKs
1001 16*4 VCLKs
1010 32*4 VCLKs
1011 64*4 VCLKs
11xx Own the bus for as long as there is a request
3-0 Timer for High Priority Requests from SB
0000 Immediate
0001 1*2 VCLKs
0010 2*2 VCLKs
0011 3*2 VCLKs
0100 4*2 VCLKs............................................ default
0101 5*2 VCLKs
0110 6*2 VCLKs
0111 7*2 VCLKs
1000 8*2 VCLKs
1001 16*2 VCLKs
1010 32*2 VCLKs
1011 64*2 VCLKs
11xx Own the bus for as long as there is a request