Writing values to a register - PXA270

Jan 23, 2006 0 Replies

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.


./devmem2 0x44000004


/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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