msm: Ensure droop detectors do not affect krait PLLs

The Droop detector mechanism present in Glitch-Free (GFMUX)
goes to nondeterministic state during frequent
standalone power collapse operation. It affects
Krait PLL output so that the PLL won't lock to
required frequency.

Since Droop detector isn't used, set sc_pdn (PLL_CLAMP)
permanently high to ensure droop detector is off and it
does not affect Krait PLL.
CRs-Fixed: 381144

Conflicts:

	arch/arm/mach-msm/Kconfig
	arch/arm/mach-msm/Makefile

Change-Id: I69a0dffeccaa3837302d6e3dd53f6b62fa683368
Signed-off-by: Jay Chokshi <jchokshi@codeaurora.org>
Signed-off-by: Neha Pandey <nehap@codeaurora.org>
diff --git a/arch/arm/mach-msm/Kconfig b/arch/arm/mach-msm/Kconfig
index a161180..82468c8 100644
--- a/arch/arm/mach-msm/Kconfig
+++ b/arch/arm/mach-msm/Kconfig
@@ -177,6 +177,7 @@
 	select ARM_HAS_SG_CHAIN
 	select MSM_KRAIT_WFE_FIXUP
 	select MSM_IOMMU_GPU_SYNC
+	select MSM_CPU_PWRCTL
 
 config ARCH_MSM8930
 	bool "MSM8930"
@@ -210,6 +211,7 @@
 	select ARM_HAS_SG_CHAIN
 	select MSM_KRAIT_WFE_FIXUP
 	select MSM_IOMMU_GPU_SYNC
+	select MSM_CPU_PWRCTL
 
 config ARCH_APQ8064
 	bool "APQ8064"
@@ -238,6 +240,7 @@
 	select ARM_HAS_SG_CHAIN
 	select MSM_KRAIT_WFE_FIXUP
 	select MSM_IOMMU_GPU_SYNC
+	select MSM_CPU_PWRCTL
 
 config ARCH_MSM8974
 	bool "MSM8974"
@@ -2593,4 +2596,11 @@
 	  can be read and written to send character data to the sysmon port of
 	  the modem over USB.
 
+config MSM_CPU_PWRCTL
+	bool "Ensures that krait droop detectors are always off"
+	help
+	  Droop detector mechanism can adversely affect krait plls during
+	  stand alone power collapse operation. Selecting this option
+	  ensures that they are always off.
+
 endif