MPC8540 datasheet(917/1302 Pages) FREESCALE

917 / 1302 page

Functional Description

MPC8540 PowerQUICC III Integrated Host Processor Reference Manual, Rev. 1

Freescale Semiconductor

16-95

For PCI-X type 0 configuration cycles, the MPC8540 translates the device number field of PCI

CFG_ADDR into a unique IDSEL signal for up to 15 different devices. Each device connects its

IDSEL input to one of the AD[31:17] signals. For PCI-X type 0 configuration cycles, the

MPC8540 translates the device number to ADn as shown in Table 16-63.

For PCI-X type 0 translations, the function number and register number fields are copied without

modification onto PCI_AD[15:2] during the address phase. PCI_AD[1:0] are driven to 0b00

during the address phase for PCI-X type 0 configuration cycles. The MPC8540 implements

address stepping on configuration cycles so that the target’s IDSEL, which is connected directly

to one of the PCI_AD lines, reaches a stable value. This means that a valid address and command

are driven on PCI_AD[31:0] and PCI_C/BE[3:0] four clocks before the assertion of PCI_FRAME.

PCI-X configuration transactions include an attribute phase one clock cycle after the address

phase. The the attribute for a configuration transaction is similar to the DWORD transaction

attribute. For the configuration attribute, PCI_C/BE[3:0] provide the byte enables and AD[31:0]

are driven as shown in Figure 16-80.

Figure 16-80. AD[31:0] During PCI-X Configuration Attribute Phase

Table 16-63. PCI-X Type 0 Configuration—Device Number to ADn Translation

Device Number

AD Signal Used for IDSEL

Device Number

AD Signal Used for IDSEL

Binary

Decimal

Binary

Decimal

0b0_0000

—

0b0_1001

AD25

0b0_0001

AD17

0b0_1010

AD26

0b0_0010

AD18

0b0_1011

AD27

0b0_0011

AD19

0b0_1100

AD28

0b0_0100

AD20

0b0_1101

AD29

0b0_0101

AD21

0b0_1110

AD30

0b0_0110

AD22

0b0_1111

AD31

0b0_0111

AD23

0b1_xxxx

—

0b0_1000

AD24

0b1_1111 1

1 A device number of all ones indicates a PCI-X special-cycle or interrupt-acknowledge transaction.

—

000

Tag

Requester Bus Number

Requester Device Number

Requester Function

Number

Secondary Bus Number

MPC8540 Datasheet(PDF) 917 Page - Freescale Semiconductor, Inc

MPC8540 Datasheet(HTML) 917 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL