[PATCH 06/27] ARM: EXYNOS:: Enter a15 lowpower mode for Exynos3250 based on Cortex-a7

Chanwoo Choi cw00.choi at samsung.com
Thu Apr 10 02:28:23 PDT 2014


This patch decide proper lowpower mode of either a15 or a9 according to own ID
from Main ID register.

Signed-off-by: Chanwoo Choi <cw00.choi at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
---
 arch/arm/mach-exynos/hotplug.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-exynos/hotplug.c b/arch/arm/mach-exynos/hotplug.c
index 5eead53..36d3db6 100644
--- a/arch/arm/mach-exynos/hotplug.c
+++ b/arch/arm/mach-exynos/hotplug.c
@@ -135,13 +135,20 @@ void __ref exynos_cpu_die(unsigned int cpu)
 	int primary_part = 0;
 
 	/*
-	 * we're ready for shutdown now, so do it.
-	 * Exynos4 is A9 based while Exynos5 is A15; check the CPU part
+	 * we're ready for shutdown now, so do it. Exynos4 is A9 based
+	 * while Exynos5 is A15/Exynos7 is A7; check the CPU part
 	 * number by reading the Main ID register and then perform the
 	 * appropriate sequence for entering low power.
 	 */
 	asm("mrc p15, 0, %0, c0, c0, 0" : "=r"(primary_part) : : "cc");
-	if ((primary_part & 0xfff0) == 0xc0f0)
+
+	/*
+	 * Main ID register of Cortex series
+	 * - Cortex-a7  : 0x410F_C07x
+	 * - Cortex-a15 : 0x410F_C0Fx
+	 */
+	primary_part = primary_part & 0xfff0;
+	if (primary_part == 0xc0f0 || primary_part == 0xc070)
 		cpu_enter_lowpower_a15();
 	else
 		cpu_enter_lowpower_a9();
-- 
1.8.0




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