ENGR00241003-1 mx6: need to add delay in LDO voltage setting

1.LDO ramp up time may be modified by ROM code
according to fuse setting, cpu freq driver use
fixed delay time which assume the LDO ramp up time
is the reset value of ANATOP register, need to set
it to reset value in regulator init.

2.The regulator set voltage should take care of
the ramp up time, calculate the ramp up time based
of register setting and to the delay, make sure that
when the set voltage function return, the voltage is
stable enough.

3.CPUFreq no need to use delay, it is already taken
care by regulator voltage setting.

Signed-off-by: Anson Huang <b20788@freescale.com>

1 files changed, 24 insertions, 9 deletions

diff --git a/arch/arm/mach-mx6/cpu_regulator-mx6.c b/arch/arm/mach-mx6/cpu_regulator-mx6.c
index cb08cad48204..fdbe22cd50e7 100644
--- a/arch/arm/mach-mx6/cpu_regulator-mx6.c
+++ b/arch/arm/mach-mx6/cpu_regulator-mx6.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2012 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright (C) 2012-2013 Freescale Semiconductor, Inc. All Rights Reserved.
  */
 
 /*
@@ -73,13 +73,34 @@ void mx6_cpu_regulator_init(void)
 		} else {
 			curr_cpu = clk_get_rate(cpu_clk);
 			cpu_op_tbl = get_cpu_op(&cpu_op_nr);
-			/* Set the core to max frequency requested. */
+
+			soc_regulator = regulator_get(NULL, soc_reg_id);
+			if (IS_ERR(soc_regulator))
+				printk(KERN_ERR "%s: failed to get soc regulator\n",
+					__func__);
+			else
+				/* set soc to highest setpoint voltage. */
+				regulator_set_voltage(soc_regulator,
+					      cpu_op_tbl[0].soc_voltage,
+					      cpu_op_tbl[0].soc_voltage);
+
+			pu_regulator = regulator_get(NULL, pu_reg_id);
+			if (IS_ERR(pu_regulator))
+				printk(KERN_ERR "%s: failed to get pu regulator\n",
+					__func__);
+			else
+				/* set pu to higheset setpoint voltage. */
+				regulator_set_voltage(pu_regulator,
+					      cpu_op_tbl[0].pu_voltage,
+					      cpu_op_tbl[0].pu_voltage);
+			/* set the core to higheset setpoint voltage. */
 			regulator_set_voltage(cpu_regulator,
 					      cpu_op_tbl[0].cpu_voltage,
 					      cpu_op_tbl[0].cpu_voltage);
+
 			clk_set_rate(cpu_clk, cpu_op_tbl[0].cpu_rate);
 
-			/*Fix loops-per-jiffy */
+			/* fix loops-per-jiffy */
 #ifdef CONFIG_SMP
 			for_each_online_cpu(cpu)
 				per_cpu(cpu_data, cpu).loops_per_jiffy =
@@ -102,11 +123,5 @@ void mx6_cpu_regulator_init(void)
 #endif
 		}
 	}
-	soc_regulator = regulator_get(NULL, soc_reg_id);
-	if (IS_ERR(soc_regulator))
-		printk(KERN_ERR "%s: failed to get soc regulator\n", __func__);
-	pu_regulator = regulator_get(NULL, pu_reg_id);
-	if (IS_ERR(pu_regulator))
-		printk(KERN_ERR "%s: failed to get pu regulator\n", __func__);
 }