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Altera_Forum's avatar
Altera_Forum
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15 years ago

How to get physical address in Windows

I need to test PCIe DMA suported by Stratix4GX HardIP. In order to perform DMA transactions from PCIe card to System Memory, I need to request Windows to allocate some memory. In additioin, I need to pass the PHYSICAL address to DMA logic so it can generate cycles to system memory. I am using C programming language and not sure how to do that in Windows XP.

4 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Access to physical addresses is reserved to Windows kernel drivers. The Microsoft device driver kit (DDK) has all necessary informations and tools to achieve it.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Jungo WinDriver has the wizard utility, I am curious if that can be utilized to request a block of physical memory. Though I do not have the windriver wizard utility installed yet. I do see the WinDriver under Jungo in device manager.

    I will see how I can utilize the WdDma_Lock function
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    15 years ago

    Remember that you will either need to have allocated memory that is physically continuous, or allow for physical address discontinuities at page boundaries (assume a 4k page if you don't know the page size).