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Re: PCI-enum and SouthBridge behaviour...

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 James Harris wrote:
...
>> Type detection isn't too hard, just read vendor- and device-ID.

> For the chipset? Where from? Something in the PCI scan?

Yes, I compare the first four bytes of PCI-config blocks to match 
what's in my (very short) list and check on version if found. 

> Early machines had motherboard or machine identification in the top 
> bytes of the ROM.

isn't this methode obsolete since many years ?

> ...
>>> Your PCI scan won't take long, will it?

>> No, only a few mS if I just scan until all desired are found, but a full
>> scan over all possible 256 busses would take seconds.

> Wouldn't you only attempt to scan a non-root PCI bus if you discover a 
> bridge to it? IIRC PCI configs for bridges give the downstream bus 
> number. So you wouldn't need to scan 256 busses unless you had a veeery 
> big machine. ;-)

bridges allow communication between apart busses, but devices like 
USB hosts, sound, graphic, LAN, firewire,.. should all show up on the 
BUS where they are connected to. 

While I know most details on motherboard and chipset in my machines 
including BUS-Device-Function for onchip devices, there may be a few 
new addons on the board which become configured by the BIOS. So my 
onboard sound report its PCI-config on BUS_07 and firewire on BUS_3.
__
wolfgang 

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Thread

PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-22 21:53 +0200
  Re: PCI-enum and SouthBridge behaviour... James Harris <james.harris.1@gmail.com> - 2016-07-24 16:52 +0100
    Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-24 19:54 +0200
      Re: PCI-enum and SouthBridge behaviour... James Harris <james.harris.1@gmail.com> - 2016-07-25 07:07 +0100
        Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-25 11:04 +0200
          Re: PCI-enum and SouthBridge behaviour... James Harris <james.harris.1@gmail.com> - 2016-07-25 10:30 +0100
            Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-25 14:06 +0200
              Re: PCI-enum and SouthBridge behaviour... James Harris <james.harris.1@gmail.com> - 2016-07-25 13:16 +0100
                Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-26 13:09 +0200
                Re: PCI-enum and SouthBridge behaviour... James Harris <james.harris.1@gmail.com> - 2016-07-26 15:14 +0100
          Re: PCI-enum and SouthBridge behaviour... Rod Pemberton <NoHaveNotOne@bcczxcfrze.cam> - 2016-07-25 21:55 -0400
            Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-26 12:48 +0200
  Re: PCI-enum and SouthBridge behaviour... Rod Pemberton <NoHaveNotOne@bcczxcfrze.cam> - 2016-07-26 08:18 -0400
    Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-26 20:11 +0200
  Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-28 18:53 +0200
    Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-29 19:47 +0200
      Re: PCI-enum and SouthBridge behaviour... Rod Pemberton <NoHaveNotOne@zxdehrnyya.cam> - 2016-07-29 17:44 -0400
        Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-30 09:44 +0200
    Re: PCI-enum and SouthBridge behaviour... James Harris <james.harris.1@gmail.com> - 2016-07-30 12:55 +0100
      Re: PCI-enum and SouthBridge behaviour... "wolfgang kern" <nowhere@never.at> - 2016-07-30 19:40 +0200
        Re: PCI-enum and SouthBridge behaviour... James Harris <james.harris.1@gmail.com> - 2016-07-30 19:08 +0100

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