[PATCH 1/3] remoteproc: imx_rproc: skip clock enable when M-core is managed by the SCU

[Hiago De Franco <hiagofranco@gmail.com>]

From: Hiago De Franco <hiago.franco@toradex.com>

For the i.MX8X and i.MX8 family SoCs, when the M-core is powered up
before Linux starts (e.g., by the bootloader) and it is being managed by
the SCU, the SCFW will not allow the kernel to enable the clock again.
This currently causes an SCU fault reset when the M-core is up and
running and the kernel boots, resetting the system.

Therefore, add a check in the clock enable function to not execute it if
the M-core is being managed by the SCU.

This change affects only the i.MX8X and i.MX8 family SoCs, as this is
under the IMX_RPROC_SCU_API method.

Signed-off-by: Hiago De Franco <hiago.franco@toradex.com>
Suggested-by: Peng Fan <peng.fan@oss.nxp.com>
---
 drivers/remoteproc/imx_rproc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/remoteproc/imx_rproc.c b/drivers/remoteproc/imx_rproc.c
index 74299af1d7f1..627e57a88db2 100644
--- a/drivers/remoteproc/imx_rproc.c
+++ b/drivers/remoteproc/imx_rproc.c
@@ -1029,8 +1029,8 @@ static int imx_rproc_clk_enable(struct imx_rproc *priv)
 	struct device *dev = priv->dev;
 	int ret;
 
-	/* Remote core is not under control of Linux */
-	if (dcfg->method == IMX_RPROC_NONE)
+	/* Remote core is not under control of Linux or it is managed by SCU API */
+	if (dcfg->method == IMX_RPROC_NONE || dcfg->method == IMX_RPROC_SCU_API)
 		return 0;
 
 	priv->clk = devm_clk_get(dev, NULL);
-- 
2.39.5