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/include/asm/epapr_hcalls.h b/arch/powerpc/include/asm/epapr_hcalls.h
index c0c7adc..833ce2c 100644 (file)
--- a/arch/powerpc/include/asm/epapr_hcalls.h
+++ b/arch/powerpc/include/asm/epapr_hcalls.h
@@ -50,10 +50,6 @@
 #ifndef _EPAPR_HCALLS_H
 #define _EPAPR_HCALLS_H
 
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <asm/byteorder.h>
-
 #define EV_BYTE_CHANNEL_SEND           1
 #define EV_BYTE_CHANNEL_RECEIVE                2
 #define EV_BYTE_CHANNEL_POLL           3
@@ -109,6 +105,11 @@
 #define EV_UNIMPLEMENTED       12      /* Unimplemented hypercall */
 #define EV_BUFFER_OVERFLOW     13      /* Caller-supplied buffer too small */
 
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <asm/byteorder.h>
+
 /*
  * Hypercall register clobber list
  *
@@ -506,5 +507,5 @@ static inline unsigned int ev_idle(void)
 
        return r3;
 }
-
+#endif /* !__ASSEMBLY__ */
 #endif

diff --git a/arch/powerpc/kernel/epapr_hcalls.S b/arch/powerpc/kernel/epapr_hcalls.S
index 697b390..62c0dc2 100644 (file)
--- 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:

diff --git a/arch/powerpc/kernel/epapr_paravirt.c b/arch/powerpc/kernel/epapr_paravirt.c
index 028aeae..f3eab85 100644 (file)
--- a/arch/powerpc/kernel/epapr_paravirt.c
+++ b/arch/powerpc/kernel/epapr_paravirt.c
@@ -21,6 +21,10 @@
 #include <asm/epapr_hcalls.h>
 #include <asm/cacheflush.h>
 #include <asm/code-patching.h>
+#include <asm/machdep.h>
+
+extern void epapr_ev_idle(void);
+extern u32 epapr_ev_idle_start[];
 
 bool epapr_paravirt_enabled;
 
@@ -41,8 +45,13 @@ static int __init epapr_paravirt_init(void)
        if (len % 4 || len > (4 * 4))
                return -ENODEV;
 
-       for (i = 0; i < (len / 4); i++)
+       for (i = 0; i < (len / 4); i++) {
                patch_instruction(epapr_hypercall_start + i, insts[i]);
+               patch_instruction(epapr_ev_idle_start + i, insts[i]);
+       }
+
+       if (of_get_property(hyper_node, "has-idle", NULL))
+               ppc_md.power_save = epapr_ev_idle;
 
        epapr_paravirt_enabled = true;