but am not sure how exactly do I read the Bar.
PCI Scanning (continued from Enumarating USB)
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naiksidd_85
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Re: PCI Scanning (continued from Enumarating USB)
Came back after a long time and yes the answere did work for me too.
but am not sure how exactly do I read the Bar.
but am not sure how exactly do I read the Bar.
Learning a lot these days THANKS to OSdev users
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Combuster
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Re: PCI Scanning (continued from Enumarating USB)
the BAR contains the base address in physical memory where that device expects some data.
To get more info about it, write all ones, then read it back. Some bits at the bottom tell things about the kind of range, but for the most part, the highest unsettable bit indicates the BAR's size (the settable bits above it will be matched to the address, and if they match, the device will do something with the data and the rest of the address)
Don't forget to restore the original value
To get more info about it, write all ones, then read it back. Some bits at the bottom tell things about the kind of range, but for the most part, the highest unsettable bit indicates the BAR's size (the settable bits above it will be matched to the address, and if they match, the device will do something with the data and the rest of the address)
Don't forget to restore the original value