thermal: imx_tmu: enable monitoring and default alert/critical

Set default critical/alert temperature and enabling monoitoring.

Without calling imx_tmu_enable_msite() monitoring will not be enabled
and read_temperature will return 0. Additionally without setting alert
temperature will cause imx_tmu_get_temp() to spin indefiniately thinking
the system needs to cool.

This resolves the board spinning endlessly when enabling IMX_TMU in the
SPL.

Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Tim Harvey <tharvey@gateworks.com>

drivers/thermal/imx_tmu.c

@@ -344,6 +344,7 @@ static int imx_tmu_bind(struct udevice *dev)
 	ofnode node, offset;
 	const char *name;
 	const void *prop;
+	int minc, maxc;
 
 	debug("%s dev name %s\n", __func__, dev->name);
 
@@ -352,6 +353,10 @@ static int imx_tmu_bind(struct udevice *dev)
 		return 0;
 
 	pdata->zone_node = 1;
+	/* default alert/crit temps based on temp grade */
+	get_cpu_temp_grade(&minc, &maxc);
+	pdata->critical = maxc * 1000;
+	pdata->alert = (maxc - 10) * 1000;
 
 	node = ofnode_path("/thermal-zones");
 	ofnode_for_each_subnode(offset, node) {
@@ -443,6 +448,7 @@ static int imx_tmu_probe(struct udevice *dev)
 	if (pdata->zone_node) {
 		imx_tmu_init(dev);
 		imx_tmu_calibration(dev);
+		imx_tmu_enable_msite(dev);
 	} else {
 		imx_tmu_enable_msite(dev);
 	}