arm:am33xx: Add a scale_vcores() hook

Similar to OMAP4/5 we need to scale the voltage up prior to changing the
clock frequencies up higher.  Add a similar hook to start with.

Signed-off-by: Tom Rini <trini@ti.com>

arch/arm/cpu/armv7/am33xx/clock.c

@@ -170,8 +170,19 @@ void do_enable_clocks(u32 *const *clk_domains,
 	};
 }
 
+/*
+ * Before scaling up the clocks we need to have the PMIC scale up the
+ * voltages first.  This will be dependent on which PMIC is in use
+ * and in some cases we may not be scaling things up at all and thus not
+ * need to do anything here.
+ */
+__weak void scale_vcores(void)
+{
+}
+
 void prcm_init()
 {
 	enable_basic_clocks();
+	scale_vcores();
 	setup_dplls();
 }

arch/arm/include/asm/arch-am33xx/clock.h

@@ -107,6 +107,7 @@ const struct dpll_params *get_dpll_mpu_params(void);
 const struct dpll_params *get_dpll_core_params(void);
 const struct dpll_params *get_dpll_per_params(void);
 const struct dpll_params *get_dpll_ddr_params(void);
+void scale_vcores(void);
 void do_setup_dpll(const struct dpll_regs *, const struct dpll_params *);
 void prcm_init(void);
 void enable_basic_clocks(void);