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January 23, 2006, 11:46 am

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.

/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
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.

/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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