pciconfig_read(2)
NAME
pciconfig_read, pciconfig_write, pciconfig_iobase - pci device information handling
SYNOPSIS
#include <pci.h> int pciconfig_read(unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len, void *buf); int pciconfig_write(unsigned long bus, unsigned long dfn, unsigned long off, unsigned long len, void *buf); int pciconfig_iobase(long which, unsigned long bus, unsigned long devfn);
DESCRIPTION
Most of the interaction with PCI devices is already handled by the kernel PCI layer, and thus these calls should not normally need to be
accessed from userspace.
- 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 either 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 appropriately.
- pciconfig_write()
- On success zero is returned. On error, -1 is returned and errno is set appropriately.
- pciconfig_iobase()
- Returns information on locations of various I/O regions in physical 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 pcicon
- fig_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
- defined).
- EOPNOTSUPP
- This return value is only valid 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().
CONFORMING TO
These calls are Linux-specific, available since Linux 2.0.26/2.1.11.
SEE ALSO
COLOPHON
- This page is part of release 3.25 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.