[U-Boot] [PATCH V3] imx: mx7: fix the temperature checking for Rev1.1

[Peng Fan]

To TO1.0, we can not rely on finish bit to read temperature. But to
TO1.1, the issue was fixed by IC, we can rely on finish bit for
temperature reading for TO1.1.

Signed-off-by: Peng Fan <peng.fan at nxp.com>
Cc: Stefano Babic <sbabic at denx.de>
Cc: Tim Harvey <tharvey at gateworks.com>
Cc: Fabio Estevam <fabio.estevam at freescale.com>
Cc: Adrian Alonso <aalonso at freescale.com>
---

Changes V3:
 Fix build warning.

Changes V2:
 Discard reading register each time in the while loop for TO1.0.
 No need to do this. Discard udelay for TO1.1 when reading register.

 drivers/thermal/imx_thermal.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/thermal/imx_thermal.c b/drivers/thermal/imx_thermal.c
index 09a3c52..6578271 100644
--- a/drivers/thermal/imx_thermal.c
+++ b/drivers/thermal/imx_thermal.c
@@ -130,7 +130,7 @@ static int read_cpu_temperature(struct udevice *dev)
 #elif defined(CONFIG_MX7)
 static int read_cpu_temperature(struct udevice *dev)
 {
-	unsigned int reg, tmp, start;
+	unsigned int reg, tmp;
 	unsigned int raw_25c, te1;
 	int temperature;
 	unsigned int *priv = dev_get_priv(dev);
@@ -169,18 +169,25 @@ static int read_cpu_temperature(struct udevice *dev)
 	writel(TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK, &ccm_anatop->tempsense1_clr);
 	writel(TEMPMON_HW_ANADIG_TEMPSENSE1_MEASURE_TEMP_MASK, &ccm_anatop->tempsense1_set);
 
-	start = get_timer(0);
-	/* Wait max 100ms */
-	do {
+	if (soc_rev() >= CHIP_REV_1_1) {
+		while ((readl(&ccm_anatop->tempsense1) &
+		       TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK) == 0)
+			;
+		reg = readl(&ccm_anatop->tempsense1);
+		tmp = (reg & TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_MASK)
+		       >> TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_SHIFT;
+	} else {
 		/*
-		 * Since we can not rely on finish bit, use 1ms delay to get
-		 * temperature. From RM, 17us is enough to get data, but
-		 * to gurantee to get the data, delay 100ms here.
+		 * Since we can not rely on finish bit, use 10ms
+		 * delay to get temperature. From RM, 17us is
+		 * enough to get data, but to gurantee to get
+		 * the data, delay 10ms here.
 		 */
+		udelay(10000);
 		reg = readl(&ccm_anatop->tempsense1);
 		tmp = (reg & TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_MASK)
 		       >> TEMPMON_HW_ANADIG_TEMPSENSE1_TEMP_VALUE_SHIFT;
-	} while (get_timer(0) < (start + 100));
+	}
 
 	writel(TEMPMON_HW_ANADIG_TEMPSENSE1_FINISHED_MASK, &ccm_anatop->tempsense1_clr);
 
-- 
2.6.2