Re: [PATCH 3/3] xen/x86: Implement x86_apic_ops

From: Konrad Rzeszutek Wilk
Date: Wed Mar 21 2012 - 12:45:48 EST


On Tue, Mar 20, 2012 at 06:31:37PM -0700, Suresh Siddha wrote:
> On Tue, 2012-03-20 at 20:12 -0400, Konrad Rzeszutek Wilk wrote:
> > Or rather just implement one different function as opposed
> > to the native one : the read function.
> >
> > We synthesize the values.
> >
> > Suggested-by: Suresh Siddha <suresh.b.siddha@xxxxxxxxx>
> > Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
> > ---
> > arch/x86/xen/Makefile | 2 +-
> > arch/x86/xen/apic.c | 17 +++++++++++++++++
> > arch/x86/xen/enlighten.c | 2 ++
> > arch/x86/xen/xen-ops.h | 4 ++++
> > 4 files changed, 24 insertions(+), 1 deletions(-)
> > create mode 100644 arch/x86/xen/apic.c
> >
> > diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile
> > index add2c2d..96ab2c0 100644
> > --- a/arch/x86/xen/Makefile
> > +++ b/arch/x86/xen/Makefile
> > @@ -20,5 +20,5 @@ obj-$(CONFIG_EVENT_TRACING) += trace.o
> > obj-$(CONFIG_SMP) += smp.o
> > obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= spinlock.o
> > obj-$(CONFIG_XEN_DEBUG_FS) += debugfs.o
> > -obj-$(CONFIG_XEN_DOM0) += vga.o
> > +obj-$(CONFIG_XEN_DOM0) += apic.o vga.o
> > obj-$(CONFIG_SWIOTLB_XEN) += pci-swiotlb-xen.o
> > diff --git a/arch/x86/xen/apic.c b/arch/x86/xen/apic.c
> > new file mode 100644
> > index 0000000..c53b3ef
> > --- /dev/null
> > +++ b/arch/x86/xen/apic.c
> > @@ -0,0 +1,17 @@
> > +#include <linux/init.h>
> > +#include <asm/x86_init.h>
> > +
> > +unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
> > +{
> > + if (reg == 0x1)
> > + return 0x00170020;
> > + else if (reg == 0x0)
> > + return 0x00000000;
>
> For IO-APIC ID register (0), you can probably use the argument 'apic' to
> set the ID bits in the returned register.

ok, that would be just
return 0x0000000 | apic

right? Since the last 8 bits are the apic value?
>
> > +
> > + return 0xfd;
>
> 0xff might be better.

<nods> Done!
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/