external PCI board direct access

[frederic dumoulin <frederic_dumoulin@eve-team.com>]

Hi,

I've got an external PCI board

/proc/pci gives me :
      Non-prefetchable 32 bit memory at 0xfeaff800 [0xfeaff800].
      I/O at 0xd800 [0xd801].
      Non-prefetchable 32 bit memory at 0xfeaa0000 [0xfeaa0000].
      Non-prefetchable 32 bit memory at 0xfea80000 [0xfea80000].

I'd like to access to memory at 0xfea80000 which is a SDRAM on my
external board

in my driver I made
baseAddress=0xfea80000;
sramSize=0x00020000;
ptr = (u_int *) ioremap (baseAddress, sramSize)

thanks to the pointer ptr I can access to the memory :
        for (i = 0; i < 0x10; i++)
                writel (i, the.ptrAccess + i);

        for (i = 0; i < 0x10; i++)
                printk ("at 0x%08x  got 0x%08x\n", i, readl
(the.ptrAccess + i));


---------

I want to do the same thing from my application.
I can export ptr via an ioctl () access in order to do :
        for (i = 0; i < 0x10; i++)
                (*(volatile u_int *) (ptr + i)) = i;

        for (i = 0; i < 0x10; i++)
                printf ("at 0x%08x  got 0x%08x\n", i, (*(volatile u_int
*) (ptr + i)));

as soon as I access to (*(volatile u_int *) (ptr + i)) I've got a
"Segmentation fault (core dumped)"




Can somebody tell me if I forgot something or what is the best method to
do this direct memory access.


Best regards.



Frédéric Dumoulin
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