Configuring IRIX

Neither of these facilities is available in the same way under IRIX. Each EISA device is configured to IRIX using a VECTOR line in a file stored in the directory /var/sysgen/system (see "System Configuration Files").

The syntax of a VECTOR line is documented in two places:

• The /var/sysgen/system/irix.sm file itself contains descriptive comments on the syntax and meaning of the statement, as well as numerous examples.

• The system(4) reference page gives a more formal definition of the syntax.

The important elements in a VECTOR line for EISA are as follows:

bustype	Specified as EISA for EISA devices. The VECTOR statement can be used for other types of buses as well.
module	The base name of a kernel-level device driver for this device, as used in the /var/sysgen/master.d database (see "Master Configuration Database" and "How Names Are Used in Configuration").
adapter	The number of the EISA bus where the device is attached--always 0, or omitted, in current systems.
ctlr	The "controller" number is simply an integer parameter that is passed to the device driver at boot time. It can be used for example to specify a slot number.
iospace, iospace2, iospace3	Each iospace group specifies the address space, the starting address, and the size of a segment of address space used by this device.
probe or exprobe	Specifies a hardware test that can be applied at boot time to find out if the device exists.

The following is a typical VECTOR line for an EISA device (it must be a single physical line in the file):

VECTOR: bustype=EISA module=if_ec3 ctlr=1
iospace=(EISAIO,0x1000,0x1000)
exprobe_space=(r,EISAIO, 0x1c80,4,0x6010d425,0xffffffff)

Using the iospace Parameters

• A keyword for the address space, either EISAIO or EISAMEM.

• The starting address, which depends on the address space and the card itself, as follows:

  • For the I/O space of an EISA card, the starting address of I/O registers is 0x1000 multiplied by the slot number of the card (from 1 to 4), and extends for a length of 0x1000 (4096). For example, the manufacturer ID of the card in slot 2 is at address 0x1C80.

  • The I/O space of an ISA card is hard-wired or jumpered on the card, and falls in the range 0x0100 to 0x0400.

  • The EISAMEM space is card-dependent and falls in the range 0x000A 0000 through 0x06FF FFFF.

• The length of this bus address range.

Using the probe and exprobe Parameters

An example exprobe parameter is as follows:

exprobe_space=(r,EISAIO, 0x1c80,4,0x6010d425,0xffffffff)

Sequence	One or more of w for write, r for read, or rn for read-negate.
Space	EISAIO or EISAMEM.
Address	The address of the byte, halfword, or word to test.
Length	The number of bytes to test: 1, 2, or 4.
Value	The value to write, or the test value for a read.
Mask	A number to be ANDed with the Value operand before a write or after a read. Specify 0xffffffff to nullify the AND operation.

You can use the w operation to prime a device. You can use the r operation to test for a specific value, and the rn operation to test that a specific value (or a specific bit, after masking) is not returned.

Typically, a simple r operation is used on an EISA card to test for the manufacturer's product identifier.

To test the existence of an ISA card, use a wr sequence to write a value to a register and read it back unchanged. Or read a value and verify that it does not come back all-binary-1, the value returned by a nonexistent device.

Using the module Parameter

You use the iospace parameters to pass in the exact bus addresses that correspond to this device. Up to three address space ranges can be passed to the driver. This does not restrict the device--it can use other ranges of addresses, but the device driver has to deduce their addresses from other information. The device driver typically uses this data to set up PIO maps (see "Mapping PIO Addresses").