Messages in this thread |  | | | Date | Fri, 14 May 2004 13:19:26 +0200 | | From | Vojtech Pavlik <> | | Subject | Re: [PATCH] HPET driver |
| |
On Thu, May 13, 2004 at 07:49:22PM -0400, Jeff Garzik wrote: > Andrew Morton wrote: > >Jeff Garzik <jgarzik@pobox.com> wrote: > > > >>>+ vma->vm_flags |= (VM_IO | VM_SHM | VM_LOCKED); > >>>+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > >>>+ addr = __pa(addr); > >> > >>where did these flags come from? don't you just want VM_RESERVED? > > > > > >VM_IO is the way to mark mmapped I/O devices. > > > > vma->vm_flags |= VM_IO; > > > >should be sufficient here. > > > >hm, I'm trying to decrypt how the driver accesses the hardware. It's > >taking copies of kernel virtual addresses based off hpet_virt_address, but > >there are no readl's or writel's in there. Is the actual device access > >done over in time_hpet.c? > > > HPET writes into RAM at magic addresses, so it's not really a bus address.
Since it lives in the bridge (either north or south), IMO it is a bus address ... at least on AMD machines it's the same space where MMIO comes from.
> Thus I think only VM_RESERVED is needed... > > Jeff
-- Vojtech Pavlik SuSE Labs, SuSE CR - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
|  |