1 files changed, 63 insertions, 10 deletions

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index d64feb3ea0be..c1f190858701 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -354,7 +354,7 @@ static int alloc_dispatch_log_kmem_cache(void)
 }
 early_initcall(alloc_dispatch_log_kmem_cache);
 
-static void pSeries_idle(void)
+static void pseries_lpar_idle(void)
 {
 	/* This would call on the cpuidle framework, and the back-end pseries
 	 * driver to  go to idle states
@@ -362,10 +362,22 @@ static void pSeries_idle(void)
 	if (cpuidle_idle_call()) {
 		/* On error, execute default handler
 		 * to go into low thread priority and possibly
-		 * low power mode.
+		 * low power mode by cedeing processor to hypervisor
 		 */
-		HMT_low();
-		HMT_very_low();
+
+		/* Indicate to hypervisor that we are idle. */
+		get_lppaca()->idle = 1;
+
+		/*
+		 * Yield the processor to the hypervisor.  We return if
+		 * an external interrupt occurs (which are driven prior
+		 * to returning here) or if a prod occurs from another
+		 * processor. When returning here, external interrupts
+		 * are enabled.
+		 */
+		cede_processor();
+
+		get_lppaca()->idle = 0;
 	}
 }
 
@@ -430,6 +442,32 @@ static void pSeries_machine_kexec(struct kimage *image)
 }
 #endif
 
+#ifdef __LITTLE_ENDIAN__
+long pseries_big_endian_exceptions(void)
+{
+	long rc;
+
+	while (1) {
+		rc = enable_big_endian_exceptions();
+		if (!H_IS_LONG_BUSY(rc))
+			return rc;
+		mdelay(get_longbusy_msecs(rc));
+	}
+}
+
+static long pseries_little_endian_exceptions(void)
+{
+	long rc;
+
+	while (1) {
+		rc = enable_little_endian_exceptions();
+		if (!H_IS_LONG_BUSY(rc))
+			return rc;
+		mdelay(get_longbusy_msecs(rc));
+	}
+}
+#endif
+
 static void __init pSeries_setup_arch(void)
 {
 	panic_timeout = 10;
@@ -456,15 +494,14 @@ static void __init pSeries_setup_arch(void)
 
 	pSeries_nvram_init();
 
-	if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
+	if (firmware_has_feature(FW_FEATURE_LPAR)) {
 		vpa_init(boot_cpuid);
-		ppc_md.power_save = pSeries_idle;
-	}
-
-	if (firmware_has_feature(FW_FEATURE_LPAR))
+		ppc_md.power_save = pseries_lpar_idle;
 		ppc_md.enable_pmcs = pseries_lpar_enable_pmcs;
-	else
+	} else {
+		/* No special idle routine */
 		ppc_md.enable_pmcs = power4_enable_pmcs;
+	}
 
 	ppc_md.pcibios_root_bridge_prepare = pseries_root_bridge_prepare;
 
@@ -687,6 +724,22 @@ static int __init pSeries_probe(void)
 	/* Now try to figure out if we are running on LPAR */
 	of_scan_flat_dt(pseries_probe_fw_features, NULL);
 
+#ifdef __LITTLE_ENDIAN__
+	if (firmware_has_feature(FW_FEATURE_SET_MODE)) {
+		long rc;
+		/*
+		 * Tell the hypervisor that we want our exceptions to
+		 * be taken in little endian mode. If this fails we don't
+		 * want to use BUG() because it will trigger an exception.
+		 */
+		rc = pseries_little_endian_exceptions();
+		if (rc) {
+			ppc_md.progress("H_SET_MODE LE exception fail", 0);
+			panic("Could not enable little endian exceptions");
+		}
+	}
+#endif
+
 	if (firmware_has_feature(FW_FEATURE_LPAR))
 		hpte_init_lpar();
 	else