Warner Losh 7138b71d5f Do not write to those config registers that are unambiguously defined ... in the various pci specifications as readonly. vendor, subvendor, device and subdevice are required to be loaded in hardware by some means that isn't the system BIOS or other system software (although some devices do have ways of accomplishing this). class and subclass are defined to be read-only in section 6.2.1 (v2.2). Apart from the status register, which we weren't touching, these are the only read-only registers I could find in the 2.2 spec. progif is also defined as being read-only in section 6.2.1. However, the PCI IDE programming document specifically states that some of the bits are read/write. Since we may have to restore registers before we have a driver attached, go ahead and restore this one byte when transitioning between D3 and D0. The PCI spec also says that writes to reserved and unimplemented registers must be completed normally. It makes no statements about writes to read-only registers, so be as conservative as possible, while covering the exception to the rule that is documented in a subpart of the standard. Requested by: socttl		2004-05-24 15:52:57 +00:00
..
eisa_pci.c
fixup_pci.c
ignore_pci.c
isa_pci.c	Convert callers to the new bus_alloc_resource_any(9) API.	2004-03-17 17:50:55 +00:00
pci_if.m
pci_pci.c	Omnibus PCI commit:	2004-04-09 15:44:34 +00:00
pci_private.h	Omnibus PCI commit:	2004-04-09 15:44:34 +00:00
pci_user.c	Device megapatch 4/6:	2004-02-21 21:10:55 +00:00
pci.c	Do not write to those config registers that are unambiguously defined	2004-05-24 15:52:57 +00:00
pcib_if.m
pcib_private.h
pcireg.h
pcivar.h	Remove advertising clause from University of California Regent's	2004-04-07 20:46:16 +00:00