Shutoff iMX8 when passing critical temperature
* The busy loop that polls beyond alert doesn't reduce the power
consumption at all.
* Adds using SNVS register writes to explicitly disable the PMIC when
the temperature exceeds critical.
* Drops power from ~5W to 300 mW (for entire board).
* Note: a full power cycle is needed to recover.
Change-Id: Ic9292555fe15c4288822704bca617a89f7ec0f05
diff --git a/drivers/thermal/nxp_tmu.c b/drivers/thermal/nxp_tmu.c
index c170c98..96a4842 100644
--- a/drivers/thermal/nxp_tmu.c
+++ b/drivers/thermal/nxp_tmu.c
@@ -134,6 +134,19 @@
}
}
+#define SNVS_LPCR 0x38
+static void mx8_snvs_poweroff(void)
+{
+ u32 value;
+ void __iomem *mx8_snvs_base = (void __iomem *)SNVS_HP_BASE_ADDR;
+
+ value = readl(mx8_snvs_base + SNVS_LPCR);
+ /* Set TOP and DP_EN bit to put the PMIC into dumb mode and
+ * explicity disable.*/
+ writel(value | 0x60, mx8_snvs_base + SNVS_LPCR);
+ /* The PMIC will pull power and execution won't continue */
+}
+
int nxp_tmu_get_temp(struct udevice *dev, int *temp)
{
struct nxp_tmu_plat *pdata = dev_get_platdata(dev);
@@ -146,8 +159,15 @@
return ret;
}
+
while (cpu_tmp >= pdata->alert) {
- printf("CPU Temperature (%dC) has beyond alert (%dC), close to critical (%dC)",
+ if (cpu_tmp >= pdata->critical) {
+ printf("Critical temperature hit. Shutting down,
+ a power cycle will be necessary\n");
+ mx8_snvs_poweroff();
+ }
+
+ printf("CPU Temperature (%dC) has exceeded alert (%dC), close to critical (%dC)",
cpu_tmp, pdata->alert, pdata->critical);
puts(" waiting...\n");
mdelay(pdata->polling_delay);
