Re: ioremap: How to

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Have you tried mmap()ing /dev/mem? You would then directly access 0x10000 - start + base, where base is the address of the virtual memory that mmap assigned to your pages, and start is the first address of physical memory that you actually specified to map.

You should avoid mapping any more pages than you need, so the addresses you specify depend on the physical page size of your processor architecture. If you need to write an interrupt handler, or if there are other processes in the system that will try to access your display device, you must write a kernel device driver.

I want build an application that requires the exact memory address (for LCD display). I use ioremap to achieve that. However, when i try to compile the file, i get the following error.

implicit declaration of ioremap
and hence
unreferenced ioremap

I assume that this is becuase I can use ioremap only in kernel mode. I have tried using ioperm and iopl, but these work only on intel architecure and my platform does not support this. Nor do i have the device file /dev/port for my platform.

Is there are any way, I can access and set the memory directly in the user(application) mode ? I do want to avoid building a driver and recompiling with the kernel.

The source code is as simple as
void main()

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