remoteproc: imx_dsp_rproc: Simplify IMX_RPROC_SCU_API switch case

Introduce imx_dsp_rproc_scu_api_{start, stop, detect_mode}() helper
functions for i.MX variants using IMX_RPROC_SCU_API to manage remote
processors.

Allows the removal of the IMX_RPROC_SCU_API switch-case blocks from
imx_dsp_rproc_[start,stop,detect_mode](), resulting in cleaner and more
maintainable code.

No functional changes.

Reviewed-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
Reviewed-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Tested-by: Iuliana Prodan <iuliana.prodan@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20251119-imx-dsp-2025-11-19-v4-9-adafd342d07b@nxp.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>

Author: MrVan

drivers/remoteproc/imx_dsp_rproc.c

@@ -346,6 +346,13 @@ static int imx_dsp_rproc_mmio_start(struct rproc *rproc)
 	return regmap_update_bits(priv->regmap, dcfg->src_reg, dcfg->src_mask, dcfg->src_start);
 }
 
+static int imx_dsp_rproc_scu_api_start(struct rproc *rproc)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+
+	return imx_sc_pm_cpu_start(priv->ipc_handle, IMX_SC_R_DSP, true, rproc->bootaddr);
+}
+
 /*
  * Start function for rproc_ops
  *
@@ -368,12 +375,6 @@ static int imx_dsp_rproc_start(struct rproc *rproc)
 	}
 
 	switch (dcfg->method) {
-	case IMX_RPROC_SCU_API:
-		ret = imx_sc_pm_cpu_start(priv->ipc_handle,
-					  IMX_SC_R_DSP,
-					  true,
-					  rproc->bootaddr);
-		break;
 	case IMX_RPROC_RESET_CONTROLLER:
 		ret = reset_control_deassert(priv->run_stall);
 		break;
@@ -398,6 +399,13 @@ static int imx_dsp_rproc_mmio_stop(struct rproc *rproc)
 	return regmap_update_bits(priv->regmap, dcfg->src_reg, dcfg->src_mask, dcfg->src_stop);
 }
 
+static int imx_dsp_rproc_scu_api_stop(struct rproc *rproc)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+
+	return imx_sc_pm_cpu_start(priv->ipc_handle, IMX_SC_R_DSP, false, rproc->bootaddr);
+}
+
 /*
  * Stop function for rproc_ops
  * It clears the REMOTE_IS_READY flags
@@ -421,12 +429,6 @@ static int imx_dsp_rproc_stop(struct rproc *rproc)
 	}
 
 	switch (dcfg->method) {
-	case IMX_RPROC_SCU_API:
-		ret = imx_sc_pm_cpu_start(priv->ipc_handle,
-					  IMX_SC_R_DSP,
-					  false,
-					  rproc->bootaddr);
-		break;
 	case IMX_RPROC_RESET_CONTROLLER:
 		ret = reset_control_assert(priv->run_stall);
 		break;
@@ -1055,6 +1057,13 @@ static int imx_dsp_rproc_mmio_detect_mode(struct rproc *rproc)
 	return 0;
 }
 
+static int imx_dsp_rproc_scu_api_detect_mode(struct rproc *rproc)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+
+	return imx_scu_get_handle(&priv->ipc_handle);
+}
+
 /**
  * imx_dsp_rproc_detect_mode() - detect DSP control mode
  * @priv: private data pointer
@@ -1078,11 +1087,6 @@ static int imx_dsp_rproc_detect_mode(struct imx_dsp_rproc *priv)
 		return dcfg->ops->detect_mode(priv->rproc);
 
 	switch (dsp_dcfg->dcfg->method) {
-	case IMX_RPROC_SCU_API:
-		ret = imx_scu_get_handle(&priv->ipc_handle);
-		if (ret)
-			return ret;
-		break;
 	case IMX_RPROC_RESET_CONTROLLER:
 		priv->run_stall = devm_reset_control_get_exclusive(dev, "runstall");
 		if (IS_ERR(priv->run_stall)) {
@@ -1320,6 +1324,12 @@ static const struct imx_rproc_plat_ops imx_dsp_rproc_ops_mmio = {
 	.detect_mode	= imx_dsp_rproc_mmio_detect_mode,
 };
 
+static const struct imx_rproc_plat_ops imx_dsp_rproc_ops_scu_api = {
+	.start		= imx_dsp_rproc_scu_api_start,
+	.stop		= imx_dsp_rproc_scu_api_stop,
+	.detect_mode	= imx_dsp_rproc_scu_api_detect_mode,
+};
+
 /* Specific configuration for i.MX8MP */
 static const struct imx_rproc_dcfg dsp_rproc_cfg_imx8mp = {
 	.att		= imx_dsp_rproc_att_imx8mp,
@@ -1352,7 +1362,7 @@ static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8ulp = {
 static const struct imx_rproc_dcfg dsp_rproc_cfg_imx8qxp = {
 	.att		= imx_dsp_rproc_att_imx8qxp,
 	.att_size	= ARRAY_SIZE(imx_dsp_rproc_att_imx8qxp),
-	.method		= IMX_RPROC_SCU_API,
+	.ops		= &imx_dsp_rproc_ops_scu_api,
 };
 
 static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8qxp = {
@@ -1363,7 +1373,7 @@ static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8qxp = {
 static const struct imx_rproc_dcfg dsp_rproc_cfg_imx8qm = {
 	.att		= imx_dsp_rproc_att_imx8qm,
 	.att_size	= ARRAY_SIZE(imx_dsp_rproc_att_imx8qm),
-	.method		= IMX_RPROC_SCU_API,
+	.ops		= &imx_dsp_rproc_ops_scu_api,
 };
 
 static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8qm = {

drivers/remoteproc/imx_rproc.h

@@ -20,8 +20,6 @@ enum imx_rproc_method {
 	IMX_RPROC_NONE,
 	/* Through ARM SMCCC */
 	IMX_RPROC_SMC,
-	/* Through System Control Unit API */
-	IMX_RPROC_SCU_API,
 	/* Through Reset Controller API */
 	IMX_RPROC_RESET_CONTROLLER,
 };