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11 capability pointer, 12 interrupt line register – Intel GD82559ER User Manual

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Datasheet

53

Networking Silicon — GD82559ER

7.1.10

PCI Subsystem Vendor ID and Subsystem ID Registers

The Subsystem Vendor ID field identifies the vendor of an 82559ER-based solution. The
Subsystem Vendor ID values are based upon the vendor’s PCI Vendor ID and is controlled by the
PCI Special Interest Group (SIG).

The Subsystem ID field identifies the 82559ER-based specific solution implemented by the vendor
indicated in the Subsystem Vendor ID field.

The 82559ER provides support for configurable Subsystem Vendor ID and Subsystem ID fields.
After hardware reset is de-asserted, the 82559ER automatically reads addresses Ah through Ch of
the EEPROM. The first of these 16-bit values is used for controlling various 82559ER functions.
The second is the Subsystem ID value, and the third is the Subsystem Vendor ID value. Again, the
default values for the Subsystem ID and Subsystem Vendor ID are 0h and 0H, respectively.

The 82559ER checks bit numbers 15, 14, and 13 in the EEPROM, word Ah and functions
according to

Table 7

below.

Note:

The Revision ID is subject to change according to the silicon stepping.

The above table implies that if the 82559ER detects the presence of an EEPROM (as indicated by a
value of 01b in bits 15 and 14), then bit number 13 determines whether the values read from the
EEPROM, words Bh and CH, will be loaded into the Subsystem ID (word BH) and Subsystem
Vendor ID (word CH) fields. If bits 15 and 14 equal 01b and bit 13 equals 1b, the three least
significant bits of the Revision ID field are programmed by bits 8-10 of the first EEPROM word,
word AH.

Between the de-assertion of reset and the completion of the automatic EEPROM read, the
82559ER does not respond to any PCI configuration cycles. If the 82559ER happens to be accessed
during this time, it will Retry the access. More information on Retry is provided in

Section

4.2.1.1.3, “Retry Premature Accesses” on page 17

.

7.1.11

Capability Pointer

The Capability Pointer is a hard coded byte register with a value of DCH. It provides an offset
within the Configuration Space for the location of the Power Management registers.

7.1.12

Interrupt Line Register

The Interrupt Line register identifies which system interrupt request line on the interrupt contoller
the device’s PCI interrupt request pin (as defined in the Interrupt Pin register) is routed to.

Table 7. 82559ER ID Fields Programming

Bits 15, 14

Bit 13

Device ID

Vendor ID

Revision ID

Subsystem ID

Subsystem

Vendor ID

11b, 10b,
00b

X

1209H

8086H

09H

0000H

(Default)

0000H

(Default)

01b

0b

1209H

8086H

09H

Word BH

Word CH

01b

1b

1209H

8086H

Word AH,
bits 10:8

Word BH

Word CH