1*e5cc2e7eSschwarze.\" $OpenBSD: pchb.4,v 1.18 2013/07/16 16:05:49 schwarze Exp $ 28a67408cSmickey.\" 32a1b39abSmickey.\" Michael Shalayeff, 2000. Public Domain. 48a67408cSmickey.\" 5*e5cc2e7eSschwarze.Dd $Mdocdate: July 16 2013 $ 68a67408cSmickey.Dt PCHB 4 78a67408cSmickey.Os 88a67408cSmickey.Sh NAME 98a67408cSmickey.Nm pchb 108a67408cSmickey.Nd PCI-Host Bridge 118a67408cSmickey.Sh SYNOPSIS 12afb7f3acSmickey.Cd "pchb* at pci?" 137908d52fSmiod.Cd "pci* at pchb?" 148a67408cSmickey.Sh DESCRIPTION 158a67408cSmickeyThe 168a67408cSmickey.Nm 17d9b934b9Sjmcdriver provides support for PCI-Host adapter-specific functions. 18d9b934b9SjmcSupport is provided for the following devices: 19d9b934b9Sjmc.Bl -tag -width Ds -offset indent 2077b69735Smickey.It i450 PCIset (Orion) 21df9fa2d9SjmcSupports additional PCI buses. 2277b69735Smickey.It Reliance Computer ROSB4, CNB20HE, CNB20LE 23df9fa2d9SjmcSupports additional PCI buses. 2477b69735Smickey.It i82424ZX (Saturn) 258a67408cSmickeyDisables CPU-PCI write posting. 2677b69735Smickey.It i82443BX 2777b69735SmickeyProvides workaround for the following errata: 2877b69735Smickey"An incorrect address may be driven on the 2977b69735SmickeyDRAM bus, resulting in memory data being 3077b69735Smickeyfetched from the wrong location." 319e84c43eSderaadt.It i82810/810E, i82815/815E, i82820, i82840 328a67408cSmickeySupports the random numbers generator, 338a67408cSmickeysupplying random bytes from the system's thermal noise. 348a67408cSmickeyDriven by periodic checks for available data from the generator, 358a67408cSmickeyit supplies entropy to the 368a67408cSmickey.Xr random 4 378a67408cSmickeydriver for common usage. 388a67408cSmickey.El 398a67408cSmickey.Pp 40d9b934b9SjmcOn amd64 and i386 systems, most PCI devices of class 418a67408cSmickey.Nm Bridge 428a67408cSmickeyand sub-class 438a67408cSmickey.Nm Bridge Host 4468c05060Smiodare supported just as PCI attachment points. 45d9b934b9SjmcA few other system control devices not listed here are supported by 46d9b934b9Sjmc.Nm . 478a67408cSmickey.Pp 487908d52fSmiodThe macppc port supports several Apple and Motorola bridges. 49aac3e221Sderaadt.Sh SEE ALSO 508a67408cSmickey.Xr intro 4 , 518a67408cSmickey.Xr pci 4 , 528a67408cSmickey.Xr random 4 538a67408cSmickey.Sh HISTORY 548a67408cSmickeyRandom number generator support first appeared in 558a67408cSmickey.Ox 2.7 . 568a67408cSmickey.Sh AUTHORS 578a67408cSmickeySupport for true RNG present on i82810 chips was added by 58*e5cc2e7eSschwarze.An Michael Shalayeff Aq Mt mickey@openbsd.org . 598a67408cSmickey.Sh BUGS 608a67408cSmickeyReal RNG probe should fix the PCI scanning loop so it would find the Firmware 618a67408cSmickeyHub (i82802) which actually contains the RNG device and 628a67408cSmickeyprobe it as a real PCI device (i.e., common PCI registers are there). 63