physical address to virtual address conversion

From: Rajesh Ghanekar (ghanekar_rajesh_at_hotmail.com)
Date: 03/30/05

  • Next message: Peter Jeremy: "Re: organization" 
    To: freebsd-hackers@freebsd.org
Date: Thu, 31 Mar 2005 00:40:15 +0530

    Hi,

       I am trying to convert a physical memory location (address 0x000F0000)
    to virtual memory address in kernel module with pmap_map() / pmap_enter().
    Whenever i call these two functions, system hangs. Is this a proper
    way for conversion?

      The same physical address can be accessed from the userspace by opening
    /dev/mem. The code which does the memory mapping to /dev/mem at kernel
    level is in ./sys/i386/i386/mem.c as mmrw() which also uses pmap_enter().

    kernel = FreeBSD 4.10

    - Rajesh

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