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From 4e6114a23a21db5741375070add8ccc16697db67 Mon Sep 17 00:00:00 2001
From: Max Krummenacher <max.krummenacher@toradex.com>
Date: Tue, 24 Sep 2019 14:15:50 +0200
Subject: [PATCH 1/2] imx_sc_thermal: prevent BUG() with rt patch
With the RT patch applied the kernel prints a BUG backtrace during boot:
| BUG: using smp_processor_id() in preemptible [00000000] code: swapper/0/1
Prevent this by avoiding the smp_processor_id call and just check both
CPU clusters which may be there in a i.MX8 series SoC.
Signed-off-by: Max Krummenacher <max.krummenacher@toradex.com>
---
drivers/thermal/imx_sc_thermal.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/drivers/thermal/imx_sc_thermal.c b/drivers/thermal/imx_sc_thermal.c
index 8c5049020cd8..51a6c73315ba 100644
--- a/drivers/thermal/imx_sc_thermal.c
+++ b/drivers/thermal/imx_sc_thermal.c
@@ -58,6 +58,7 @@ sc_ipc_t tsens_ipcHandle;
static int imx_sc_tsens_get_temp(void *data, int *temp)
{
struct imx_sc_sensor *sensor = data;
+ int hw_id;
sc_err_t sciErr;
int16_t celsius;
int8_t tenths;
@@ -65,14 +66,14 @@ static int imx_sc_tsens_get_temp(void *data, int *temp)
sciErr = sc_misc_get_temp(tsens_ipcHandle, sensor->hw_id,
SC_C_TEMP, &celsius, &tenths);
/*
- * if the SS power domain is down, read temp will fail, so
- * we can return the temp of CPU domain instead.
+ * if the SS power domain is down, read temp will fail,
+ * try the temp of the potentially two CPU domains instead.
*/
- if (sciErr != SC_ERR_NONE) {
- sciErr = sc_misc_get_temp(tsens_ipcHandle,
- sensor_hw_id[topology_physical_package_id(smp_processor_id())],
+ hw_id = 0;
+ while (sciErr != SC_ERR_NONE) {
+ sciErr = sc_misc_get_temp(tsens_ipcHandle, sensor_hw_id[hw_id++],
SC_C_TEMP, &celsius, &tenths);
- if (sciErr != SC_ERR_NONE) {
+ if (hw_id > 1) {
pr_err("read temp sensor:%d failed\n", sensor->hw_id);
return -EINVAL;
}
--
2.20.1
|
