ARM: mmp: fix potential NULL dereference
[linux/fpc-iii.git] / arch / x86 / xen / apic.c
blobec57bd3818a4cdeb0c45d3c3b13cc7a79db85f9b
1 #include <linux/init.h>
3 #include <asm/x86_init.h>
4 #include <asm/apic.h>
5 #include <asm/xen/hypercall.h>
7 #include <xen/xen.h>
8 #include <xen/interface/physdev.h>
10 unsigned int xen_io_apic_read(unsigned apic, unsigned reg)
12 struct physdev_apic apic_op;
13 int ret;
15 apic_op.apic_physbase = mpc_ioapic_addr(apic);
16 apic_op.reg = reg;
17 ret = HYPERVISOR_physdev_op(PHYSDEVOP_apic_read, &apic_op);
18 if (!ret)
19 return apic_op.value;
21 /* fallback to return an emulated IO_APIC values */
22 if (reg == 0x1)
23 return 0x00170020;
24 else if (reg == 0x0)
25 return apic << 24;
27 return 0xfd;
30 void __init xen_init_apic(void)
32 x86_io_apic_ops.read = xen_io_apic_read;