David Miller wrote:
You really need to investigate why dma_map_single() is not returning sane addresses.
I haven't reached a conclusion yet since I'm not so familiar with the Linux VM subsystem and have not had much time to look at it. But I noticed that pci_map_single does not work in later kernels. I guess it stopped working with the patch "sparc: Use asm-generic/pci-dma-compat" since before the that the physical address was obtained through virt_to_phys() and after that it goes through page_to_phys(virt_to_page()) which does not work. Using page_address(virt_to_page()) works but I understand that this does not always evaluate properly. Using page_to_phys(virt_to_page()) results in an address lacking the phys_base offset. My patch to page_to_phys (adding phys_base) several weeks ago was done because of this but I thought that the problem then was that I was using virt_to_page() on an address obtained through kmalloc which I have read is not really allowed? The page_to_phys(virt_to_page()) does not even work for memory allocated with __get_free_page() currently. I will continue investigating this when I have the time. I just wanted to give you this feedback. Maybe you understand what is going on ... Best regards, Kristoffer -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
