Writing values to a register - PXA270

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Hello everyone,

I am working on an evaluation board for a PXA270 and trying to get the
framebuffer to work. For this I have to write some values in the
register. Here is my code:

  unsigned int * reqPoint;

  reqPoint = request_region(0x44000004, 4, "my");
  //reqPoint = io_p2v(0x44000004);

  DPRINTK("reqPoint  @0x%08x;\n",  reqPoint);
  DPRINTK("reqPoint  @0x%08x;\n",  *reqPoint);

  *reqPoint = (unsigned int) 0x40;

  sleepSomeTime(10);

  DPRINTK("reqPoint  @0x%08x;\n",  reqPoint);
  DPRINTK("reqPoint  @0x%08x;\n",  *reqPoint);

the output is:
  pxafb_probe: reqPoint  @0xc3dd4440;
  pxafb_probe: reqPoint  @0xbf014e1c;
  pxafb_probe: reqPoint  @0xc3dd4440;
  pxafb_probe: reqPoint  @0x00000040;

The problem is, if I take a look to the register with  ./devmem2
0x44000004 the value is not written to the register.

Quoted text here. Click to load it
  /dev/mem opened.
  Memory mapped at address 0x40018000.
  Value at address 0x44000004 (0x40018004): 0x0

If I set some GPIOs on nearly the same way it is working.
Does anyone have a hint to help me out?
Thanks for your help.

Cons Som


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