arm: am437x: cm-t43: set MPU and CORE voltages on boot

During boot, U-Boot raises the CPU frequency but the CORE and MPU regulators
are not updated. This is not a problem in cold boot since the default values
that the pmic outputs are correct, but if Linux were to switch the module to a
low power OPP, the new voltage values will be retained after a reboot and the
module will likely hang once U-Boot raises the CPU frequency back up.

Set both CORE and MPU regulators to to 1.1V on boot.

Cc: Tom Rini <trini@konsulko.com>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Nikita Kiryanov <nikita@compulab.co.il>
Reviewed-by: Tom Rini <trini@konsulko.com>

board/compulab/cm_t43/spl.c

@@ -6,9 +6,13 @@
 
 #include <common.h>
 #include <spl.h>
+#include <i2c.h>
 #include <asm/arch/clock.h>
 #include <asm/arch/ddr_defs.h>
 #include <asm/gpio.h>
+#include <power/pmic.h>
+#include <power/tps65218.h>
+#include "board.h"
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -100,6 +104,17 @@ const struct dpll_params *get_dpll_per_params(void)
 	return &dpll_per;
 }
 
+void scale_vcores(void)
+{
+	set_i2c_pin_mux();
+	i2c_init(CONFIG_SYS_OMAP24_I2C_SPEED, CONFIG_SYS_OMAP24_I2C_SLAVE);
+	if (i2c_probe(TPS65218_CHIP_PM))
+		return;
+
+	tps65218_voltage_update(TPS65218_DCDC1, TPS65218_DCDC_VOLT_SEL_1100MV);
+	tps65218_voltage_update(TPS65218_DCDC2, TPS65218_DCDC_VOLT_SEL_1100MV);
+}
+
 void sdram_init(void)
 {
 	unsigned long ram_size;

include/configs/cm_t43.h

@@ -167,5 +167,7 @@
 #define CONFIG_SPL_SPI_SUPPORT
 #define CONFIG_SPL_SPI_FLASH_SUPPORT
 #define CONFIG_SPL_SPI_LOAD
+#define CONFIG_SPL_I2C_SUPPORT
+#define CONFIG_SPL_POWER_SUPPORT
 
 #endif	/* __CONFIG_CM_T43_H */