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Does intel in it's current generation of processors provide any Direct Memory Access(DMA) controllers? If yes is it built into the chip?

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DMA is pretty much a standard in modern chipsets. Usually it is a seperate module in the southbridge of the motherboard and not actually a part of the CPU chip itself. Modern Intel Processors such as the Sandy Bridge Line should support the technology but it is more a question of the motherboard than the CPU.

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So will it be possible for the user to program the triggering of DMA controller to perform tasks such as fetching data,while CPU is busy with other tasks? For example during the video encoding process while processor core is working with a macroblock can DMA controller be used to fetch the next macroblock in parallel? – eeuser Jun 21 '12 at 4:53
That is beyond my knowledge. – Brandon Kreisel Jun 21 '12 at 12:47

While DMA is standard in modern x86-based systems, the need for a central, dedicated DMA controller has gone: in the days of ISA, a DMA controller could be programmed to perform DMA operations on behalf of the CPU.

In modern machines, Bus Mastering is supported. This removes the need for a central DMA controller and allows individual devices - for example, PCI cards, to perform bus mastering themselves, and thus individual devices are able to perform DMA operations without needing help from a centralised DMA controller.

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While this is not about x86, I cam here while searching where I can find Information about DMA for Intel CPUs, since I spend quite a while looking through the CPU Manuals, I thought I leave this here.

While trying to figure this out I found out that the DMA controller does NOT sit on the CPU, but rather on the Chipset. I tried to figure this out and could find no information on DMA in Intels i-7 LGA 2011 manuals (except the DMA remapping info).

However if I look in the manual for my Chipset (X79 express, Intel), I can find information on the DMA Controllers (see page 101 onwards).

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If the downvoter would have left a comment, i would know what to improve... – ted Jul 6 '15 at 9:49

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