[PATCH v2 2/3] powerpc/pseries: Update dynamic cache nodes for suspend/resume operation

[Tyrel Datwyler]

From: Haren Myneni <hbabu at us.ibm.com>

From: Haren Myneni <hbabu at us.ibm.com>

pHyp can change cache nodes for suspend/resume operation. The current code
updates the device tree after all non boot CPUs are enabled. Hence, we do not
modify the cache list based on the latest cache nodes. Also we do not remove
cache entries for the primary CPU.

This patch removes the cache list for the boot CPU, updates the device tree
before enabling nonboot CPUs and adds cache list for the boot cpu.

Signed-off-by: Haren Myneni <hbabu at us.ibm.com>
Signed-off-by: Tyrel Datwyler <tyreld at linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/rtas.h |  4 ++++
 arch/powerpc/kernel/rtas.c      | 17 +++++++++++++++++
 arch/powerpc/kernel/time.c      |  6 ++++++
 3 files changed, 27 insertions(+)

diff --git a/arch/powerpc/include/asm/rtas.h b/arch/powerpc/include/asm/rtas.h
index 9bd52c6..da9d733 100644
--- a/arch/powerpc/include/asm/rtas.h
+++ b/arch/powerpc/include/asm/rtas.h
@@ -283,6 +283,10 @@ extern void pSeries_log_error(char *buf, unsigned int err_type, int fatal);
 
 #ifdef CONFIG_PPC_PSERIES
 extern int pseries_devicetree_update(s32 scope);
+extern void post_mobility_fixup(void);
+extern void update_dynamic_configuration(void);
+#else /* !CONFIG_PPC_PSERIES */
+void update_dynamic_configuration(void) { }
 #endif
 
 #ifdef CONFIG_PPC_RTAS_DAEMON
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c
index 4cf674d..8249eb2 100644
--- a/arch/powerpc/kernel/rtas.c
+++ b/arch/powerpc/kernel/rtas.c
@@ -43,6 +43,7 @@
 #include <asm/time.h>
 #include <asm/mmu.h>
 #include <asm/topology.h>
+#include "cacheinfo.h"
 
 struct rtas_t rtas = {
 	.lock = __ARCH_SPIN_LOCK_UNLOCKED
@@ -972,6 +973,22 @@ out:
 	free_cpumask_var(offline_mask);
 	return atomic_read(&data.error);
 }
+
+/*
+ * The device tree cache nodes can be modified during suspend/ resume.
+ * So delete all cache entries and recreate them again after the device tree
+ * update.
+ * We already deleted cache entries for notboot CPUs before suspend. So delete
+ * entries for the primary CPU, recreate entries after the device tree update.
+ * We can create entries for nonboot CPU when enable them later.
+ */
+
+void update_dynamic_configuration(void)
+{
+	cacheinfo_cpu_offline(smp_processor_id());
+	post_mobility_fixup();
+	cacheinfo_cpu_online(smp_processor_id());
+}
 #else /* CONFIG_PPC_PSERIES */
 int rtas_ibm_suspend_me(struct rtas_args *args)
 {
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index b3b1441..5f1ca28 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -69,6 +69,7 @@
 #include <asm/vdso_datapage.h>
 #include <asm/firmware.h>
 #include <asm/cputime.h>
+#include <asm/rtas.h>
 
 /* powerpc clocksource/clockevent code */
 
@@ -592,6 +593,11 @@ void arch_suspend_enable_irqs(void)
 	generic_suspend_enable_irqs();
 	if (ppc_md.suspend_enable_irqs)
 		ppc_md.suspend_enable_irqs();
+	/*
+	 * Update configuration which can be modified based on devicetree
+	 * changes during resume.
+	 */
+	update_dynamic_configuration();
 }
 #endif
 
-- 
1.7.12.4