isa(4)

NAME

isa − configuration files for ISA and EISA bus device drivers

DESCRIPTION

Solaris for x86 platforms support the ISA or EISA bus as the system bus. In this release of Solaris for x86, drivers for devices on these buses need to use driver configuration files to inform the system that the device hardware may be present. The configuration file must also specify the device I/O addresses, any interrupt capabilities that the device may have, any DMA channels it may require, and any memory-mapped addresses it may occupy.

Configuration files for ISA or EISA device drivers should identify the parent nexus driver implicitly using the class keyword. This removes the dependency on the name of the particular nexus driver involved since most drivers can operate device controllers attached to either of those two buses. The ISA and EISA nexus drivers both belong to class sysbus. See driver.conf(4) for further details of configuration file syntax.

All bus drivers of class sysbus recognize the following properties:

intr An arbitrary-length array where each element of the array consists of a pair of integers. Each array element describes a possible interrupt that the device might generate.

The first integer of each pair specifies the device’s relative priority. This is the priority that this device’s interrupt handler will receive relative to the interrupt handlers of other drivers. The priority must be an integer from 1 to 16. It is normally not recommended to specify a priority greater than 9, and you may not specify a priority of exactly 10. Generally, disks are assigned a priority of 5, while mice and printers are lower, and serial communication devices are higher, typically 7.

The second integer of each pair denotes the hardware interrupt request (IRQ) number. The driver can refer to the elements of this array by index, and register interrupt handlers with the system using ddi_add_intr(9F). The index into the array is passed as the inumber argument of ddi_add_intr().

Only devices that generate interrupts need to provide intr properties.

reg An arbitrary-length array where each element of the array consists of a 3-tuple of integers. Each array element describes a contiguous memory address range associated with the device on the bus.

The first integer of the tuple is reserved. The second integer of each 3-tuple specifies the physical address of the device in the memory address space. The third integer of each 3-tuple specifies the size, in bytes, of the mappable region.

The driver can refer to the elements of this array by index, and construct kernel mappings to these addresses using ddi_map_regs(9F). The index into the array is passed as the rnumber argument of ddi_map_regs().

All sysbus device drivers should provide reg properties, because the first two integer elements of this property are used to construct the address part of the device name under /devices. In this release of Solaris for x86, if the device has memory-mapped addresses, the first integer should be 0 and the second integer should specify the physical address; if the device does not have memory-mapped addresses, the first integer should specify a unique identifier and the second integer should be zero. A recommended unique identifier is the ioaddr value; that is, specify the I/O address in both the ioaddr field and the first integer of the reg field.

In this release of Solaris for x86, nexus drivers of class sysbus do not recognize the following properties. It is recommended that drivers for devices connected to the system bus recognize the following standard property names:

ioaddr An integer that describes the I/O port base address for this device.

dmachan An integer that specifies the DMA channel used by this device. Only devices that use a DMA channel need to provide dmachan properties.

EXAMPLES

Here are four sample entries from four different driver.conf files:

name="fdc" class="sysbus" intr=5,6 ioaddr=0x3f0 dmachan=2 reg=0x3f0,0,0;
name="logi" class="sysbus" intr=1,4 ioaddr=0x23c reg=0x23c,0,0;
name="sbpro" class="sysbus" ioaddr=0x220 intr=5,7 dmachan=1 reg=0x220,0,0;
name="smc" class="sysbus" intr=5,3 ioaddr=0x280 reg=0,0xD0000,0x2000;

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isa(4)

NAME

DESCRIPTION

EXAMPLES

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