On Dec 9, 2004, at 8:12 AM, Dmitriy Tochansky wrote:
Look ret = io_remap_page_range(start, offset, size, vma->vm_page_prot); remaps
from "offset" which I got from pci_resource_start (curdev, IOMEM0); its ok
from first board where it eq 0x40000000 but on second it 0x40002040
Read the memory mapping docuemntation and understand the APIs. All of the Linux mapping functions, whether mmap() from an application or in the kernel are going to align on page boundaries.
The address of 0x40002040 is going to be aligned to a page boundary, so you have to consider the offset into that page to the base of the device, plus the register offset. The kernel mapping functions, like remap_page_range, are going to force the alignment because that is what we expect in the kernel. An mmap() with an unaligned address will generate an error.
-- Dan
