Chapter 8: PCI/G-Bus Bridge
TX7901 User’s Manual (Rev. 6.30T – Nov, 2001)
8-24
8.3.2.2.3 g2pBase Address Registers (g2pBase0, g2pBase1, g2pBase2, g2pBase3)
The functionality of these registers is described in Section 8.3.2.2 above. The fields of these
registers are further detailed in the following figure and Table 8-10.
63
32
g2pBase [63:32]
32
31
3
2
0
g2pBase [31:3]
0
29
3
Table 8-10 g2pBase Address Register Field Descriptions
Bit(s)
Field
R/W
Description
63:3
g2pBase
R/W
Address used for base of PCI transaction. Cleared during reset. (0)
2:0
–
R/O
Reserved (0)
8.3.2.2.4 g2pCycleType
Register
(g2pCycleType)
When a PCI cycle is initiated, g2pCycleType is used to define which of the 15 possible PCI
cycle types are performed. G-Bus access to this register is allowed using the G-Bus single
cycle mode.
31
29
28
27
26
24 23
21
20
19
18
16
0
e[3]
0
type[3]
0
e[2]
0
type[2]
3
1
1
3
3
1
1
3
15
13
12
11
10
8
7
5
4
3
2
0
0
e[1]
0
type[1]
0
e[0]
0
type[0]
3
1
1
3
3
1
1
3
Table 8-11 g2pCycleType Register Field Definitions
Bit(s)
Field
R/W
Description
31:29
–
R/O
Reserved. Read back as “0”. (0)
28
e[3]
R/W
Enable for g2pWindow[3]. Cleared during reset. (0)
27
–
R/O
Reserved (0)
26:24
type[3]
R/W
Assigned to PCI C/BE[3:1]* during PCI address phase through
g2pWindow[3]. Cleared during reset. (0)
23:21
–
R/O
Reserved. Read back as ”0”. (0)
20
e[2]
R/W
Enable for g2pWindow[2]. Cleared during reset. (0)
19
0
R/O
Reserved (0)
18:16
type[2]
R/W
Assigned to PCI C/BE[3:1]* during PCI address through g2pWindow[2].
Cleared during reset. (0)
15:13
–
R/O
Reserved. Read back as “0”. (0)
Summary of Contents for TMPR7901
Page 1: ...TX System RISC TX79 Family TMPR7901 Symmetric 2 way superscalar 64 bit CPU ...
Page 14: ...Handling Precautions ...
Page 15: ......
Page 17: ...1 Using Toshiba Semiconductors Safely 1 2 ...
Page 41: ...4 Precautions and Usage Considerations 4 2 ...
Page 42: ...TX7901 User s Manual Rev 6 30T November 2001 DOCUMENT NUMBER M 99 00004 07 ...
Page 43: ......
Page 259: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 1 13 Removed ...
Page 260: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 2 ...