pciconfig_read(2) System Calls Manual pciconfig_read(2)
NAME
pciconfig_read, pciconfig_write, pciconfig_iobase - pci device informa-
tion handling
LIBRARY
Standard C library (libc, -lc)
SYNOPSIS
#include <pci.h>
int pciconfig_read(unsigned long bus, unsigned long dfn,
unsigned long off, unsigned long len,
unsigned char *buf);
int pciconfig_write(unsigned long bus, unsigned long dfn,
unsigned long off, unsigned long len,
unsigned char *buf);
int pciconfig_iobase(int which, unsigned long bus,
unsigned long devfn);
DESCRIPTION
Most of the interaction with PCI devices is already handled by the ker-
nel PCI layer, and thus these calls should not normally need to be ac-
cessed from user space.
pciconfig_read()
Reads to buf from device dev at offset off value.
pciconfig_write()
Writes from buf to device dev at offset off value.
pciconfig_iobase()
You pass it a bus/devfn pair and get a physical address for ei-
ther the memory offset (for things like prep, this is
0xc0000000), the IO base for PIO cycles, or the ISA holes if any.
RETURN VALUE
pciconfig_read()
On success, zero is returned. On error, -1 is returned and errno
is set to indicate the error.
pciconfig_write()
On success, zero is returned. On error, -1 is returned and errno
is set to indicate the error.
pciconfig_iobase()
Returns information on locations of various I/O regions in physi-
cal memory according to the which value. Values for which are:
IOBASE_BRIDGE_NUMBER, IOBASE_MEMORY, IOBASE_IO, IOBASE_ISA_IO,
IOBASE_ISA_MEM.
ERRORS
EINVAL len value is invalid. This does not apply to pciconfig_iobase().
EIO I/O error.
ENODEV For pciconfig_iobase(), "hose" value is NULL. For the other
calls, could not find a slot.
ENOSYS The system has not implemented these calls (CONFIG_PCI not de-
fined).
EOPNOTSUPP
This return value is valid only for pciconfig_iobase(). It is
returned if the value for which is invalid.
EPERM User does not have the CAP_SYS_ADMIN capability. This does not
apply to pciconfig_iobase().
STANDARDS
Linux.
HISTORY
Linux 2.0.26/2.1.11.
SEE ALSO
capabilities(7)
Linux man-pages 6.9.1 2024-05-02 pciconfig_read(2)
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