[POWERPC] check firmware state before suspending

Currently the kernel blindly halts all the processors and calls the
ibm,suspend-me rtas call.  If the firmware is not in the correct
state, we then re-start all the processors and return.  It is much
smarter to first check the firmware state, and only if it is waiting,
call the ibm,suspend-me call.

Signed-off-by: Paul Mackerras <paulus@samba.org>

3 files changed, 33 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 13496f319855..fd15e3e3bb33 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -593,9 +593,31 @@ out:
 static int rtas_ibm_suspend_me(struct rtas_args *args)
 {
         int i;
+        long state;
+        long rc;
+        unsigned long dummy;
 
         struct rtas_suspend_me_data data;
 
+        /* Make sure the state is valid */
+        rc = plpar_hcall(H_VASI_STATE,
+                         ((u64)args->args[0] << 32) | args->args[1],
+                         0, 0, 0,
+                         &state, &dummy, &dummy);
+
+        if (rc) {
+                printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned %ld\n",rc);
+                return rc;
+        } else if (state == H_VASI_ENABLED) {
+                args->args[args->nargs] = RTAS_NOT_SUSPENDABLE;
+                return 0;
+        } else if (state != H_VASI_SUSPENDING) {
+                printk(KERN_ERR "rtas_ibm_suspend_me: vasi_state returned state %ld\n",
+                       state);
+                args->args[args->nargs] = -1;
+                return 0;
+        }
+
         data.waiting = 1;
         data.args = args;
 
diff --git a/include/asm-powerpc/hvcall.h b/include/asm-powerpc/hvcall.h
index 6cc7e1fb7bfd..0d3c4e85711a 100644
--- a/include/asm-powerpc/hvcall.h
+++ b/include/asm-powerpc/hvcall.h
@@ -102,6 +102,15 @@
 #define H_PP1                   (1UL<<(63-62))
 #define H_PP2                   (1UL<<(63-63))
 
+/* VASI States */
+#define H_VASI_INVALID          0
+#define H_VASI_ENABLED          1
+#define H_VASI_ABORTED          2
+#define H_VASI_SUSPENDING       3
+#define H_VASI_SUSPENDED        4
+#define H_VASI_RESUMED          5
+#define H_VASI_COMPLETED        6
+
 /* DABRX flags */
 #define H_DABRX_HYPERVISOR      (1UL<<(63-61))
 #define H_DABRX_KERNEL          (1UL<<(63-62))
@@ -190,6 +199,7 @@
 #define H_QUERY_INT_STATE       0x1E4
 #define H_POLL_PENDING          0x1D8
 #define H_JOIN                  0x298
+#define H_VASI_STATE            0x2A4
 #define H_ENABLE_CRQ            0x2B0
 
 #ifndef __ASSEMBLY__
diff --git a/include/asm-powerpc/rtas.h b/include/asm-powerpc/rtas.h
index a3b4e55569c7..02e213e3d69f 100644
--- a/include/asm-powerpc/rtas.h
+++ b/include/asm-powerpc/rtas.h
@@ -24,6 +24,7 @@
 #define RTAS_RMOBUF_MAX (64 * 1024)
 
 /* RTAS return status codes */
+#define RTAS_NOT_SUSPENDABLE    -9004
 #define RTAS_BUSY               -2    /* RTAS Busy */
 #define RTAS_EXTENDED_DELAY_MIN 9900
 #define RTAS_EXTENDED_DELAY_MAX 9905