[PATCH 6/8] remoteproc: imx_rproc: initial support for mutilple start/stop method

[peng.fan@oss.nxp.com]

From: Peng Fan <peng.fan@nxp.com>

Add three methods IMX_RPROC_NONE(no need start/stop),
IMX_RPROC_MMIO(start/stop through mmio) and IMX_RPROC_SMC
(start/stop through ARM SMCCC).

The current SoCs supported are all using IMX_RPROC_MMIO, add a restrict
in probe that only SoCs using IMX_RPROC_MMIO needs syscon regmap to
access registers.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 drivers/remoteproc/imx_rproc.c | 52 +++++++++++++++++++++++-----------
 1 file changed, 35 insertions(+), 17 deletions(-)

diff --git a/drivers/remoteproc/imx_rproc.c b/drivers/remoteproc/imx_rproc.c
index f31b258201c2..8e545b654e54 100644
--- a/drivers/remoteproc/imx_rproc.c
+++ b/drivers/remoteproc/imx_rproc.c
@@ -84,6 +84,15 @@ enum imx_rproc_mode {
 	IMX_RPROC_EARLY_BOOT,
 };
 
+/* Remote core start/stop method */
+enum imx_rproc_method {
+	IMX_RPROC_NONE,
+	/* Through syscon regmap */
+	IMX_RPROC_MMIO,
+	/* Through ARM SMCCC */
+	IMX_RPROC_SMC,
+};
+
 struct imx_rproc_dcfg {
 	u32				src_reg;
 	u32				src_mask;
@@ -91,6 +100,7 @@ struct imx_rproc_dcfg {
 	u32				src_stop;
 	const struct imx_rproc_att	*att;
 	size_t				att_size;
+	enum imx_rproc_method		method;
 };
 
 struct imx_rproc {
@@ -194,6 +204,7 @@ static const struct imx_rproc_dcfg imx_rproc_cfg_imx8mq = {
 	.src_stop	= IMX7D_M4_STOP,
 	.att		= imx_rproc_att_imx8mq,
 	.att_size	= ARRAY_SIZE(imx_rproc_att_imx8mq),
+	.method		= IMX_RPROC_MMIO,
 };
 
 static const struct imx_rproc_dcfg imx_rproc_cfg_imx7d = {
@@ -203,6 +214,7 @@ static const struct imx_rproc_dcfg imx_rproc_cfg_imx7d = {
 	.src_stop	= IMX7D_M4_STOP,
 	.att		= imx_rproc_att_imx7d,
 	.att_size	= ARRAY_SIZE(imx_rproc_att_imx7d),
+	.method		= IMX_RPROC_MMIO,
 };
 
 static const struct imx_rproc_dcfg imx_rproc_cfg_imx6sx = {
@@ -212,6 +224,7 @@ static const struct imx_rproc_dcfg imx_rproc_cfg_imx6sx = {
 	.src_stop	= IMX6SX_M4_STOP,
 	.att		= imx_rproc_att_imx6sx,
 	.att_size	= ARRAY_SIZE(imx_rproc_att_imx6sx),
+	.method		= IMX_RPROC_MMIO,
 };
 
 static int imx_rproc_start(struct rproc *rproc)
@@ -567,16 +580,18 @@ static int imx_rproc_detect_mode(struct imx_rproc *priv)
 	int ret;
 	u32 val;
 
-	ret = regmap_read(priv->regmap, dcfg->src_reg, &val);
-	if (ret) {
-		dev_err(dev, "Failed to read src\n");
-		return ret;
-	}
+	if (priv->regmap) {
+		ret = regmap_read(priv->regmap, dcfg->src_reg, &val);
+		if (ret) {
+			dev_err(dev, "Failed to read src\n");
+			return ret;
+		}
 
-	if (!(val & dcfg->src_stop))
-		priv->mode = IMX_RPROC_EARLY_BOOT;
-	else
-		priv->mode = IMX_RPROC_NORMAL;
+		if (!(val & dcfg->src_stop))
+			priv->mode = IMX_RPROC_EARLY_BOOT;
+		else
+			priv->mode = IMX_RPROC_NORMAL;
+	}
 
 	if (priv->mode == IMX_RPROC_EARLY_BOOT) {
 		priv->rproc->state = RPROC_DETACHED;
@@ -604,16 +619,9 @@ static int imx_rproc_probe(struct platform_device *pdev)
 	struct rproc *rproc;
 	struct regmap_config config = { .name = "imx-rproc" };
 	const struct imx_rproc_dcfg *dcfg;
-	struct regmap *regmap;
+	struct regmap *regmap = NULL;
 	int ret;
 
-	regmap = syscon_regmap_lookup_by_phandle(np, "syscon");
-	if (IS_ERR(regmap)) {
-		dev_err(dev, "failed to find syscon\n");
-		return PTR_ERR(regmap);
-	}
-	regmap_attach_dev(dev, regmap, &config);
-
 	/* set some other name then imx */
 	rproc = rproc_alloc(dev, "imx-rproc", &imx_rproc_ops,
 			    NULL, sizeof(*priv));
@@ -626,6 +634,16 @@ static int imx_rproc_probe(struct platform_device *pdev)
 		goto err_put_rproc;
 	}
 
+	if (dcfg->method == IMX_RPROC_MMIO) {
+		regmap = syscon_regmap_lookup_by_phandle(np, "syscon");
+		if (IS_ERR(regmap)) {
+			dev_err(dev, "failed to find syscon\n");
+			ret = PTR_ERR(regmap);
+			goto err_put_rproc;
+		}
+		regmap_attach_dev(dev, regmap, &config);
+	}
+
 	priv = rproc->priv;
 	priv->rproc = rproc;
 	priv->regmap = regmap;
-- 
2.30.0