Messages in this thread | | | Subject | Re: HELP:(VIPER BOARD)AC'97 controller driver for rtlinux(rtlinux core driver) | From | "nitin ahuja" <> | Date | Wed, 06 Apr 2005 09:46:16 -0600 |
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Hi,
> > I am trying to develop a codec driver (rtlinux > driver) from scratch. In Viper board (PXA255) > physical memory range 0x40000000-0x43FFFFFF is used > by the PXA255 peripherals.In that address range > 0x40500000-0x405005FC is needed for AC'97 controller > registers. Is this memory range is already mapped to > virtual address space, else How to map this to > virtual address space. >
You have to map this address range using "ioremap()". Data at address returned by ioremap can be accessed by calling readl(), writel() et al
> > When i tried ioremap() it is giving same virtual > address with different physical address(i tried > ioremap with another driver(same board)with different > physical memory address) >
Same virtual address can point to different physical addresses depending upon how it is mapped.
Nitin
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