Browse Prior Art Database

Mechanism for a Host Bridge to Forward Software Generated Peripheral Component Interface Configuration Cycles in a PowerPC System

IP.com Disclosure Number: IPCOM000116467D
Original Publication Date: 1995-Sep-01
Included in the Prior Art Database: 2005-Mar-30
Document File: 4 page(s) / 105K

Publishing Venue

IBM

Related People

Amini, I: AUTHOR [+6]

Abstract

All PCI systems must provide a mechanism that allows PCI configuration cycles. There is no specification defined for other system architectures. This invention specifies a mechanism for a host bridge to forward software gener in a PowerPC*/PCI system which is compliant with the method defined for PC-AT com increased compatibility with Personal Computers based on the Intel x86** and PCI architectures.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 51% of the total text.

Mechanism for a Host Bridge to Forward Software Generated Peripheral
Component Interface Configuration Cycles in a PowerPC System

   N_TBST     TSIZ(0:2)      A(30:31)     N_CBE(3:0)
    0           XXX            XX          0000
    1           001            00          1110
    1           001            01          1101
    1           001            10          1011
    1           001            11          0111
    1           010            00          1100
    1           010            01          1001
    1           010            10          0011
    1           010            11          invalid   *
    1           011            00          1000
    1           011            01          0001
    1           011            10          invalid   *
    1           011            11          invalid   *
    1           100            00          0000
    1           100            01          invalid   *
    1           100            10          invalid   *
    1           100            11          invalid   *
  Fig. 1.  PCI byte enables N_CBE(3:0) generated from PowerPC
processor
bus signa

      All PCI systems must provide a mechanism that allows PCI
configuration cycles.  There is no specification defined for other
system architectures.  This invention specifies a mechanism for a
host bridge to forward software gener in a PowerPC*/PCI system which
is compliant with the method defined for PC-AT com increased
compatibility with Personal Computers based on the Intel x86** and
PCI architectures.

      For PC-AT compatible machines, there are two distinct
mechanisms defined to a PCI configuration cycles.  These are referred
to as Configuration Mechanism #1 and Specification Revision 2.0.
recommends Configuration Mechanism #1 as the preferr Two DWORD(4
bytes) I/O...