[PATCH 1/2] ARM: tegra: update the cache maintenance order for CPU shutdown
Joseph Lo
josephl at nvidia.com
Wed Dec 19 21:28:38 EST 2012
Updating the cache maintenance order before CPU shutdown when doing CPU
hotplug.
The old order:
* clean L1 by flush_cache_all
* exit SMP
* CPU shutdown
Adapt to:
* disable L1 data cache by clear C bit
* clean L1 by v7_flush_dcache_louis
* exit SMP
* CPU shutdown
For CPU hotplug case, it's no need to do "flush_cache_all". And we should
disable L1 data cache before clean L1 data cache. Then leaving the SMP
coherency.
Signed-off-by: Joseph Lo <josephl at nvidia.com>
---
arch/arm/mach-tegra/hotplug.c | 4 ++--
arch/arm/mach-tegra/sleep-tegra20.S | 3 ---
arch/arm/mach-tegra/sleep-tegra30.S | 3 ---
arch/arm/mach-tegra/sleep.S | 4 +++-
arch/arm/mach-tegra/sleep.h | 1 +
5 files changed, 6 insertions(+), 9 deletions(-)
diff --git a/arch/arm/mach-tegra/hotplug.c b/arch/arm/mach-tegra/hotplug.c
index dca5141..d8c683b 100644
--- a/arch/arm/mach-tegra/hotplug.c
+++ b/arch/arm/mach-tegra/hotplug.c
@@ -28,8 +28,8 @@ void __ref tegra_cpu_die(unsigned int cpu)
{
cpu = cpu_logical_map(cpu);
- /* Flush the L1 data cache. */
- flush_cache_all();
+ /* Clean L1 data cache */
+ tegra_disable_clean_inv_dcache();
/* Shut down the current CPU. */
tegra_hotplug_shutdown();
diff --git a/arch/arm/mach-tegra/sleep-tegra20.S b/arch/arm/mach-tegra/sleep-tegra20.S
index 72ce709..ad2ca07 100644
--- a/arch/arm/mach-tegra/sleep-tegra20.S
+++ b/arch/arm/mach-tegra/sleep-tegra20.S
@@ -33,9 +33,6 @@
* should never return
*/
ENTRY(tegra20_hotplug_shutdown)
- /* Turn off SMP coherency */
- exit_smp r4, r5
-
/* Put this CPU down */
cpu_id r0
bl tegra20_cpu_shutdown
diff --git a/arch/arm/mach-tegra/sleep-tegra30.S b/arch/arm/mach-tegra/sleep-tegra30.S
index 562a8e7..63a15bd 100644
--- a/arch/arm/mach-tegra/sleep-tegra30.S
+++ b/arch/arm/mach-tegra/sleep-tegra30.S
@@ -32,9 +32,6 @@
* Should never return.
*/
ENTRY(tegra30_hotplug_shutdown)
- /* Turn off SMP coherency */
- exit_smp r4, r5
-
/* Powergate this CPU */
mov r0, #TEGRA30_POWER_HOTPLUG_SHUTDOWN
bl tegra30_cpu_shutdown
diff --git a/arch/arm/mach-tegra/sleep.S b/arch/arm/mach-tegra/sleep.S
index 26afa7c..addae35 100644
--- a/arch/arm/mach-tegra/sleep.S
+++ b/arch/arm/mach-tegra/sleep.S
@@ -34,7 +34,7 @@
#include "flowctrl.h"
#include "sleep.h"
-#ifdef CONFIG_PM_SLEEP
+#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PM_SLEEP)
/*
* tegra_disable_clean_inv_dcache
*
@@ -60,7 +60,9 @@ ENTRY(tegra_disable_clean_inv_dcache)
ldmfd sp!, {r0, r4-r5, r7, r9-r11, pc}
ENDPROC(tegra_disable_clean_inv_dcache)
+#endif
+#ifdef CONFIG_PM_SLEEP
/*
* tegra_sleep_cpu_finish(unsigned long v2p)
*
diff --git a/arch/arm/mach-tegra/sleep.h b/arch/arm/mach-tegra/sleep.h
index 9821ee7..56505c3 100644
--- a/arch/arm/mach-tegra/sleep.h
+++ b/arch/arm/mach-tegra/sleep.h
@@ -106,6 +106,7 @@ exit_l2_resume:
#else
void tegra_resume(void);
int tegra_sleep_cpu_finish(unsigned long);
+void tegra_disable_clean_inv_dcache(void);
#ifdef CONFIG_HOTPLUG_CPU
void tegra20_hotplug_init(void);
--
1.7.0.4
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