MLK-10206-1 imx: mx6: Fix temperature checking issue

The current temperature checking will not stop booting when temperature
is over TEMPERATURE_MAX value. This is a bug in the temperature polling.
The patch fixes this issue by blocking the booting until the temperature
is lower than TEMPERATURE_HOT.

Signed-off-by: Ye.Li <B37916@freescale.com>

1 files changed, 17 insertions, 15 deletions

diff --git a/arch/arm/cpu/armv7/mx6/soc.c b/arch/arm/cpu/armv7/mx6/soc.c
index 3c3d2fd..207b92b 100644
--- a/arch/arm/cpu/armv7/mx6/soc.c
+++ b/arch/arm/cpu/armv7/mx6/soc.c
@@ -2,7 +2,7 @@
  * (C) Copyright 2007
  * Sascha Hauer, Pengutronix
  *
- * (C) Copyright 2009-2014 Freescale Semiconductor, Inc.
+ * (C) Copyright 2009-2015 Freescale Semiconductor, Inc.
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */
@@ -238,9 +238,8 @@ static void imx_set_wdog_powerdown(bool enable)
 	writew(enable, &wdog2->wmcr);
 }
 
-static int read_cpu_temperature(void)
+static int read_cpu_temperature(int *temperature)
 {
-	int temperature;
 	unsigned int ccm_ccgr2;
 	unsigned int reg, tmp;
 	unsigned int raw_25c, raw_n40c, ratio;
@@ -278,7 +277,7 @@ static int read_cpu_temperature(void)
 	writel(ccm_ccgr2, &mxc_ccm->CCGR2);
 
 	if (fuse == 0 || fuse == 0xffffffff || (fuse & 0xfff00000) == 0)
-		return TEMPERATURE_MIN;
+		return -EINVAL;
 
 	/*
 	 * fuse data layout:
@@ -329,35 +328,38 @@ static int read_cpu_temperature(void)
 	writel(BM_ANADIG_TEMPSENSE0_FINISHED, &mxc_ccm->tempsense0_clr);
 
 	if (tmp <= raw_n40c)
-		temperature = REG_VALUE_TO_CEL(ratio, tmp);
+		*temperature = REG_VALUE_TO_CEL(ratio, tmp);
 	else
-		temperature = TEMPERATURE_MIN;
+		*temperature = TEMPERATURE_MIN;
 	/* power down anatop thermal sensor */
 	writel(BM_ANADIG_TEMPSENSE0_POWER_DOWN, &mxc_ccm->tempsense0_set);
 	writel(BM_ANADIG_ANA_MISC0_REFTOP_SELBIASOFF, &mxc_ccm->ana_misc0_clr);
 
-	return temperature;
+	return 0;
 }
 
 void check_cpu_temperature(void)
 {
 	int cpu_tmp = 0;
+	int ret;
 
-	cpu_tmp = read_cpu_temperature();
-	while (cpu_tmp > TEMPERATURE_MIN && cpu_tmp < TEMPERATURE_MAX) {
+	ret = read_cpu_temperature(&cpu_tmp);
+	while (!ret) {
 		if (cpu_tmp >= TEMPERATURE_HOT) {
 			printf("CPU is %d C, too hot to boot, waiting...\n",
 				cpu_tmp);
 			udelay(5000000);
-			cpu_tmp = read_cpu_temperature();
-		} else
+			ret = read_cpu_temperature(&cpu_tmp);
+		} else {
+			printf("CPU:   Temperature %d C, calibration data: 0x%x\n",
+			cpu_tmp, fuse);
 			break;
+		}
 	}
-	if (cpu_tmp > TEMPERATURE_MIN && cpu_tmp < TEMPERATURE_MAX)
-		printf("CPU:   Temperature %d C, calibration data: 0x%x\n",
-			cpu_tmp, fuse);
-	else
+
+	if (ret) {
 		printf("CPU:   Temperature: can't get valid data!\n");
+	}
 }
 
 static void set_ahb_rate(u32 val)