File Formats sysbus(4)
NAME
sysbus, isa - device tree properties for ISA bus device
driversDESCRIPTION
Solaris for x86 supports the ISA bus as the system bus. Drivers for devices on this buse use the device tree built by the booting system to retrieve the necessary system resources used by the driver. These resources include deviceI/O port addresses, any interrupt capabilities that the device can have, any DMA channels it can require, and any
memory-mapped addresses it can occupy.
Configuration files for ISA device drivers are only neces-
sary to describe properties used by a particular driver that are not part of the standard properties found in the devicetree. See driver.conf(4) for further details of configura-
tion file syntax.The ISA nexus drivers all belong to class sysbus. All bus
drivers of class sysbus recognize the following properties:
interrupts An arbitrary-length array where each element
of the array represents a hardware interrupt(IRQ) that is used by the device. In gen-
eral, this array only has one entry unless a particular device uses more than one IRQ. Solaris defaults all ISA interrupts to IPL5. This interrupt priority can be overrid-
den by placing an interrupt-priorities pro-
perty in a .conf file for the driver. Each entry in the array of integers for theinterrupt-priorities property is matched
one-to-one with the elements in the inter-
rupts property to specify the IPL value that is used by the system for this interrupt in this driver. This is the priority that this device's interrupt handler receives relative to the interrupt handlers of other drivers. The priority is an integer from 1 to 16. Generally, disks are assigned a priority of 5, while mice and printers are lower, and serial communication devices are higher, typically 7. 10 is reserved by the system and must not be used. Priorities 11 and greater are high level priorities and are generally not recommended (seeddi_intr_hilevel(9F)).
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File Formats sysbus(4)
The driver can refer to the elements of thisarray by index using ddi_add_intr(9F). The
index into the array is passed as theinumber argument of ddi_add_intr().
Only devices that generate interrupts have an interrupts property.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 specifies the memory type, 0 specifies a memory range and1 specifies an I/O range. The second integer specifies the base address of the memory
range. The third integer of each 3-tuple
specifies the size, in bytes, of the mappa-
ble region. The driver can refer to the elements of thisarray by index, and construct kernel map-
pings to these addresses usingddi_map_regs(9F). The index into the array
is passed as the rnumber argument ofddi_map_regs().
All sysbus devices have reg properties.
The first tuple of this property is used to construct the address part of the device name under /devices. In the case of Plug and Play ISA devices, the first tuple is a special tuple that does not denote a memory range, but is used by the system only to create the address part of the device name. This special tuple can be recognized by determining if the top bit of the first integer is set to a one. The order of the tuples in the reg property is determined by the boot system probe code and depends on the characteristics of eachparticular device. However, the reg pro-
perty maintains the same order of entriesfrom system boot to system boot. The recom-
mended way to determine the reg property for a particular device is to use the prtconf(1M) command after installing the particular device. The output of theSunOS 5.11 Last change: 18 Nov 2004 2
File Formats sysbus(4)
prtconf command can be examined to determine the reg property for any installed device.You can use the ddi_get* and ddi_put* family
of functions to access register space from ahigh-level interrupt context.
dma-channels A list of integers that specifies the DMA
channels used by this device. Only devicesthat use DMA channels have a dma-channels
property.ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Architecture | x86 ||_____________________________|_____________________________|
SEE ALSO
prtconf(1M), driver.conf(4), scsi(4), attributes(5),ddi_add_intr(9F), ddi_intr_hilevel(9F), ddi_map_regs(9F),
ddi_prop_op(9F)
Writing Device DriversSunOS 5.11 Last change: 18 Nov 2004 3