KVM: PPC: ev_idle hcall support for e500 guests
Signed-off-by: Liu Yu <yu.liu@freescale.com>
[varun: 64-bit changes]
Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com>
Signed-off-by: Stuart Yoder <stuart.yoder@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/powerpc/kernel/epapr_hcalls.S b/arch/powerpc/kernel/epapr_hcalls.S
index 697b390..62c0dc2 100644
--- a/arch/powerpc/kernel/epapr_hcalls.S
+++ b/arch/powerpc/kernel/epapr_hcalls.S
@@ -8,13 +8,41 @@
*/
#include <linux/threads.h>
+#include <asm/epapr_hcalls.h>
#include <asm/reg.h>
#include <asm/page.h>
#include <asm/cputable.h>
#include <asm/thread_info.h>
#include <asm/ppc_asm.h>
+#include <asm/asm-compat.h>
#include <asm/asm-offsets.h>
+/* epapr_ev_idle() was derived from e500_idle() */
+_GLOBAL(epapr_ev_idle)
+ CURRENT_THREAD_INFO(r3, r1)
+ PPC_LL r4, TI_LOCAL_FLAGS(r3) /* set napping bit */
+ ori r4, r4,_TLF_NAPPING /* so when we take an exception */
+ PPC_STL r4, TI_LOCAL_FLAGS(r3) /* it will return to our caller */
+
+ wrteei 1
+
+idle_loop:
+ LOAD_REG_IMMEDIATE(r11, EV_HCALL_TOKEN(EV_IDLE))
+
+.global epapr_ev_idle_start
+epapr_ev_idle_start:
+ li r3, -1
+ nop
+ nop
+ nop
+
+ /*
+ * Guard against spurious wakeups from a hypervisor --
+ * only interrupt will cause us to return to LR due to
+ * _TLF_NAPPING.
+ */
+ b idle_loop
+
/* Hypercall entry point. Will be patched with device tree instructions. */
.global epapr_hypercall_start
epapr_hypercall_start: