|CSX_REQUESTIO(9F)||Kernel Functions for Drivers||CSX_REQUESTIO(9F)|
#include <sys/pccard.h> int32_t csx_RequestIO(client_handle_t ch, io_req_t *ir);
int32_t csx_ReleaseIO(client_handle_t ch, io_req_t *ir);
If a client requires I/O resources, csx_RequestIO() must be called to request I/O resources from Card Services; then csx_RequestConfiguration(9F) must be used to establish the configuration. csx_RequestIO() can be called multiple times until a successful set of I/O resources is found. csx_RequestConfiguration(9F) only uses the last configuration specified.
csx_RequestIO() fails if it has already been called without a corresponding csx_ReleaseIO().
csx_ReleaseIO() releases previously requested I/O resources. The Card Services window resource list is adjusted by this function. Depending on the adapter hardware, the I/O window might also be disabled.
uint32_t Socket; /* socket number*/ uint32_t Baseport1.base; /* IO range base port address */ acc_handle_t Baseport1.handle; /* IO range base address /* or port num */ uint32_t NumPorts1; /* first IO range number contiguous /* ports */ uint32_t Attributes1; /* first IO range attributes */ uint32_t Baseport2.base; /* IO range base port address */ acc_handle_t Baseport2.handle; /* IO range base address or port num */ uint32_t NumPorts2; /* second IO range number contiguous /* ports */ uint32_t Attributes2; /* second IO range attributes */ uint32_t IOAddrLines; /* number of IO address lines decoded */
The fields are defined as follows:
When calling csx_RequestIO(), the BasePort.base field specifies the first port address requested. Upon successful return from csx_RequestIO(), the BasePort.handle field contains an access handle, corresponding to the first byte of the allocated I/O window, which the client must use when accessing the PC Card's I/O space via the common access functions. A client must not make any assumptions as to the format of the returned BasePort.handle field value.
If the BasePort.base field is set to 0, Card Services returns an I/O resource based on the available I/O resources and the number of contiguous ports requested. When BasePort.base is 0, Card Services aligns the returned resource in the host system's I/O address space on a boundary that is a multiple of the number of contiguous ports requested, rounded up to the nearest power of two. For example, if a client requests two I/O ports, the resource returned will be a multiple of two. If a client requests five contiguous I/O ports, the resource returned will be a multiple of eight.
If multiple ranges are being requested, at least one of the BasePort.base fields must be non-zero.
For some combinations of host system busses and adapter hardware, the width of an I/O resource can not be set via RequestIO(); on those systems, the host bus cycle access type determines the I/O resource data path width on a per-cycle basis.
WIN_ACC_BIG_ENDIAN and WIN_ACC_LITTLE ENDIAN describe the endian characteristics of the device as big endian or little endian, respectively. Even though most of the devices will have the same endian characteristics as their busses, there are examples of devices with an I/O processor that has opposite endian characteristics of the busses. When WIN_ACC_BIG_ENDIAN or WIN_ACC_LITTLE ENDIAN is set, byte swapping will automatically be performed by the system if the host machine and the device data formats have opposite endian characteristics. The implementation may take advantage of hardware platform byte swapping capabilities.
When WIN_ACC_NEVER_SWAP is specified, byte swapping will not be invoked in the data access functions. The ability to specify the order in which the CPU will reference data is provided by the following Attributes bits. Only one of the following bits may be specified:
These values are advisory, not mandatory. For example, data can be ordered without being merged or cached, even though a driver requests unordered, merged and cached together. All other bits in the Attributes field must be set to 0.
On some systems, multiple calls to csx_RequestIO() with different BasePort, NumPorts, and/or IOAddrLines values will have to be made to find an acceptable combination of parameters that can be used by Card Services to allocate I/O resources for the client. (See NOTES).
PC Card 95 Standard, PCMCIA/JEIDA
|July 19, 1996||OmniOS|