Multi Processor Floating Pointer Structure

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mobruan
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Re: Multi Processor Floating Pointer Structure

Post by mobruan »

Hi, im still working on the code, now im trying to read the mp table entries and use this information to set the io apic redirection table. But i stay with a doubt: in the mp spec the address of the ebda area is in the segment 40:0e. The wiki tells to search at 40e, is it the same? i try to understand that but i cant...any explanation?
thanks
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thooot
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Re: Multi Processor Floating Pointer Structure

Post by thooot »

40:0e is a 16-bit address. To convert it to a linear address you need to do 0x40 * 0x10 + 0x0e = 0x40e.
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exkor
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Re: Multi Processor Floating Pointer Structure

Post by exkor »

You can check out my asm code that looks for MP in this thread
http://forum.osdev.org/viewtopic.php?f= ... 5&start=15
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Love4Boobies
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Re: Multi Processor Floating Pointer Structure

Post by Love4Boobies »

One common approach is to use ACPI instead of MP tables (if the system supports it).
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