Messages in this thread | | | Date | Sun, 5 Oct 2008 16:56:32 +0800 | From | "huang ying" <> | Subject | Re: [RFC PATCH] x86: make 64bit efi to use ioremap_cache for efi_ioremap |
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On Sun, Oct 5, 2008 at 1:44 AM, Yinghai Lu <yinghai@kernel.org> wrote: > On Sat, Oct 4, 2008 at 2:35 AM, huang ying <huang.ying.caritas@gmail.com> wrote: [...] >> Using __va and efi_ioremap() here is to make EFI support compatible >> with kexec. Because EFI provide only efi_enter_virtual_mode(), no >> efi_leave_virtual_mode(), we should make EFI runtime memory area >> mapped to same virtual memory area in original kernel and kexeced >> kernel, so that the EFI runtime services can be used in kexeced >> kernel. > > so need to make efi range all under direct-mapping like E820-RAM?
Some EFI runtime range is just some RAM area used by EFI runtime services, they can be direct-mapped. Some EFI runtime range may be IO MEM range used by EFI runtime services, it is possible that these IO MEM range can not be direct-mapped. So I implement efi_ioremap() to deal with them.
Best Regards, Huang Ying
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