Date: Wed, 1 Mar 1995 17:03:37 -0700 From: ron@apple.com (Ron Hochsprung) Subject: Item #241: PCI Binding - legacy devices P1275 Open Firmware Working Group Proposal -- Proposal #241 Ver Title: "legacy" devices Author: Ron Hochsprung Date: March 1, 1995 Ed/Tech: Technical Synopsis: define default "reg" properties for legacy devices Doc & Version: PowerPC Binding 1.4 Problem: legacy devices (without FCode) are not handled. Proposal: add a new section, as follows: section: Legacy devices 'Legacy' VGA and IDE devices that are implemented on PCI will typically have the same "hard-decoded" addresses as they did on ISA. Such devices that have FCode can use explicit inidication of the address requirements as noted above. However, for cards that have no FCode image, Open Firmware shall assume the standard address ranges and shall create the "reg" property with these ranges, in addition to any relocatable regions that have base registers. For VGA (class code = 0x000100), the address ranges are: 0x3B0-0x3BB (I/O, aliased; i.e., t=1) 0x3C0-0x3DF (I/O, aliased; i.e., t=1) 0xA0000-0xBFFFF (Memory, below 1MB, t=1) For IDE (class code = 0x010100), the address ranges are: 0x1F0-0x1F7 Primary Command Block (I/O) 0x3F6 Primary Control Block (I/O) 0x170-0x17F Secondary Command Block (I/O) 0x376 Secondary Control Block (I/O) Note: For IDE, an encoding of the low-order byte of the class-code (the "programming model" field) can be encoded to indicate the ability of the device to operate in other than 'compatility' mode. See the PCI IDE Cotnroller Specification for more detail. [ P1275 Item #241 -- Received: Wed Mar 1 17:07:18 PST 1995 ]