[PATCH 6/8] bus: fsl-mc: pause the MC firmware when unloading

From: laurentiu . tudor
Date: Thu Jul 15 2021 - 10:07:52 EST


From: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>

Pause the MC firmware when unloading the driver so that it doesn't
crash in certain scenarios, such as kexec.

Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>
---
drivers/bus/fsl-mc/fsl-mc-bus.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/bus/fsl-mc/fsl-mc-bus.c b/drivers/bus/fsl-mc/fsl-mc-bus.c
index 41861ca5c8f1..e5b4830cf3c5 100644
--- a/drivers/bus/fsl-mc/fsl-mc-bus.c
+++ b/drivers/bus/fsl-mc/fsl-mc-bus.c
@@ -1207,6 +1207,16 @@ static int fsl_mc_bus_remove(struct platform_device *pdev)

bus_unregister_notifier(&fsl_mc_bus_type, &fsl_mc_nb);

+ if (mc->fsl_mc_regs) {
+ /*
+ * Pause the MC firmware so that it doesn't crash in certain
+ * scenarios, such as kexec.
+ */
+ writel(readl(mc->fsl_mc_regs + FSL_MC_GCR1) |
+ (GCR1_P1_STOP | GCR1_P2_STOP),
+ mc->fsl_mc_regs + FSL_MC_GCR1);
+ }
+
return 0;
}

--
2.17.1