msm: acpuclock-krait: Enable HFPLL for init only if switching to it

The existing code left the HFPLL enabled in hfpll_init(), even if
the CPU was detected to be at a non-HFPLL rate. Correct this for
power savings between when hfpll_init() and the first runtime CPU
frequency switch happen. This also ensure votes for HFPLL
regulators are not left unnecessarily asserted.

Change-Id: Iaca5dc7e4769bdbd494d669726ba9b500256f793
Signed-off-by: Matt Wagantall <mattw@codeaurora.org>
diff --git a/arch/arm/mach-msm/acpuclock-krait.c b/arch/arm/mach-msm/acpuclock-krait.c
index 9566cea..aaf3b76 100644
--- a/arch/arm/mach-msm/acpuclock-krait.c
+++ b/arch/arm/mach-msm/acpuclock-krait.c
@@ -620,9 +620,8 @@
 		writel_relaxed(drv.hfpll_data->droop_val,
 			       sc->hfpll_base + drv.hfpll_data->droop_offset);
 
-	/* Set an initial rate and enable the PLL. */
+	/* Set an initial PLL rate. */
 	hfpll_set_rate(sc, tgt_s);
-	hfpll_enable(sc, false);
 }
 
 static int __cpuinit rpm_regulator_init(struct scalable *sc, enum vregs vreg,
@@ -793,7 +792,9 @@
 	regval &= ~(0x3 << 6);
 	set_l2_indirect_reg(sc->l2cpmr_iaddr, regval);
 
-	/* Switch to the target clock source. */
+	/* Enable and switch to the target clock source. */
+	if (tgt_s->src == HFPLL)
+		hfpll_enable(sc, false);
 	set_pri_clk_src(sc, tgt_s->pri_src_sel);
 	sc->cur_speed = tgt_s;