On Tue, Sep 09, 2014 at 05:26:49PM +0100, Catalin Marinas wrote: > On Mon, Sep 01, 2014 at 03:57:40PM +0100, Hanjun Guo wrote: > > diff --git a/arch/arm64/include/asm/acenv.h b/arch/arm64/include/asm/acenv.h > > new file mode 100644 > > index 0000000..3899ee6 > > --- /dev/null > > +++ b/arch/arm64/include/asm/acenv.h > > @@ -0,0 +1,18 @@ > > +/* > > + * ARM64 specific ACPICA environments and implementation > > + * > > + * Copyright (C) 2014, Linaro Ltd. > > + * Author: Hanjun Guo <hanjun.guo@xxxxxxxxxx> > > + * Author: Graeme Gregory <graeme.gregory@xxxxxxxxxx> > > + * > > + * This program is free software; you can redistribute it and/or modify > > + * it under the terms of the GNU General Public License version 2 as > > + * published by the Free Software Foundation. > > + */ > > + > > +#ifndef _ASM_ACENV_H > > +#define _ASM_ACENV_H > > + > > +#define ACPI_FLUSH_CPU_CACHE() WARN_ONCE(1, "Not currently supported on ARM64") > > Does this mean that it will be supported at some point? >From what I recall it's impossible to support as we have no equivalent of WBINVD -- the possibility migration of dirty cache lines renders it impossible to guarantee that the caches remain empty (or that data even left the local caches in the first place). > Looking at the places where this function is called, I don't really > see how this would ever work on ARM. Which means that we add such > macro just to be able to compile code that would never be used on > arm64. I would rather see the relevant ACPI files only compiled on > x86/IA-64 rather than arm64. Agreed. It looks like include/acpi/platform/acenv.h defines an empty ACPI_FLUSH_CPU_CACHE() stub, so something else should probably be done to turn the use of ACPI_FLUSH_CPU_CACHE() into a build-time bug on arm64. Mark. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
