_CA_PCI_Read_Config_DWord()

read a double word from the configuration space of a device

Synopsis:

#include <sys/pci.h>
int _CA_PCI_Read_Config_DWord (
        unsigned busnum,
        unsigned devfuncname,
        unsigned offset,
        unsigned cnt,
        char *bufptr);

Description:

This function reads the specified number of double words from the configuration space of the given device or function.

The arguments are as follows:

busnum

the bus number

devfuncname

the name of the device or function

offset

the register offset into the configuration space. This offset must be aligned to a double-word boundary (that is, 0, 4, 8, ..., 252)

cnt

the number of double words to read

bufptr

a pointer to a buffer where the requested double words are placed

Returns:

PCI_SUCCESS

the device or function was found

PCI_BAD_REGISTER_NUMBER

an invalid register offset was given

Examples:

See _CA_PCI_Find_Device().

Classification:

Intel

Caveats:

When you use the _CA_PCI_... functions:

• Your program must be linked for privity level 1, and the process must be run by the superuser (root) or a setuid program that's owned by the superuser but started by a regular user. For more information on privity, see the cc -T option or the Linker PRIVILEGE option.
• The stack size must be less than 64K.

See also:

_CA_PCI_BIOS_Present(), _CA_PCI_Find_Class(), _CA_PCI_Find_Device(), _CA_PCI_GenerateSpecialCycle(), _CA_PCI_Read_Config_Byte(), _CA_PCI_Read_Config_Word(), _CA_PCI_Write_Config_Byte(), _CA_PCI_Write_Config_DWord(), _CA_PCI_Write_Config_Word()