Hi there, I am trying to access a hardware timer implemented in an FPGA from user space. I implemented a simple mmap() functionality (taken from Runbini's Linux Device Driver)
int simple_remap_mmap(struct file *filp, struct vm_area_struct *vma) { unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; if (offset >= __pa(high_memory) || (filp->f_flags & O_SYNC)) { vma->vm_flags |= VM_IO; } vma->vm_flags |= VM_RESERVED; if (remap_page_range(vma->vm_start, offset, vma->vm_end-vma->vm_start, vma->vm_page_prot)) return -EAGAIN; return 0; } I just learned that > getting an uncached user space mapping is architecture dependent. > On ARM, however, passing pgprot_noncached(vma->vm_page_prot) to > remap_page_range() will alter the page protections such that the > mapping will be uncached. How could I do this on an MPC8xx? Thanks a million! -- Steven Scholz imc Measurement & Control imc Me?systeme GmbH Voltastr. 5 Voltastr. 5 13355 Berlin 13355 Berlin Germany Deutschland ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/