pinctrl: Add pinctrl driver for i.MX8

Add pinctrl driver for i.MX8. The pads configuration is controlled
by SCU, so need to ask SCU to configure pads through scfw API.
Add pinctrl-scu to invoke sc_pad_set to configure pads.
Add a new flag IMX8_USE_SCU to differentiate i.MX8 from other platforms
which could directly configure pads from Acore side.
Add CONFIG_PINCTRL_IMX8 as the built gate.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
Cc: Stefano Babic <sbabic@denx.de>
diff --git a/drivers/pinctrl/nxp/pinctrl-imx.c b/drivers/pinctrl/nxp/pinctrl-imx.c
index 36e1e89..04ea82a 100644
--- a/drivers/pinctrl/nxp/pinctrl-imx.c
+++ b/drivers/pinctrl/nxp/pinctrl-imx.c
@@ -28,7 +28,9 @@
 
 	dev_dbg(dev, "%s: %s\n", __func__, config->name);
 
-	if (info->flags & SHARE_MUX_CONF_REG)
+	if (info->flags & IMX8_USE_SCU)
+		pin_size = SHARE_IMX8_PIN_SIZE;
+	else if (info->flags & SHARE_MUX_CONF_REG)
 		pin_size = SHARE_FSL_PIN_SIZE;
 	else
 		pin_size = FSL_PIN_SIZE;
@@ -58,112 +60,127 @@
 
 	npins = size / pin_size;
 
-	/*
-	 * Refer to linux documentation for details:
-	 * Documentation/devicetree/bindings/pinctrl/fsl,imx-pinctrl.txt
-	 */
-	for (i = 0; i < npins; i++) {
-		mux_reg = pin_data[j++];
-
-		if (!(info->flags & ZERO_OFFSET_VALID) && !mux_reg)
-			mux_reg = -1;
+	if (info->flags & IMX8_USE_SCU) {
+		imx_pinctrl_scu_conf_pins(info, pin_data, npins);
+	} else {
+		/*
+		 * Refer to linux documentation for details:
+		 * Documentation/devicetree/bindings/pinctrl/fsl,imx-pinctrl.txt
+		 */
+		for (i = 0; i < npins; i++) {
+			mux_reg = pin_data[j++];
 
-		if (info->flags & SHARE_MUX_CONF_REG) {
-			conf_reg = mux_reg;
-		} else {
-			conf_reg = pin_data[j++];
-			if (!(info->flags & ZERO_OFFSET_VALID) && !conf_reg)
-				conf_reg = -1;
-		}
+			if (!(info->flags & ZERO_OFFSET_VALID) && !mux_reg)
+				mux_reg = -1;
 
-		if ((mux_reg == -1) || (conf_reg == -1)) {
-			dev_err(dev, "Error mux_reg or conf_reg\n");
-			devm_kfree(dev, pin_data);
-			return -EINVAL;
-		}
+			if (info->flags & SHARE_MUX_CONF_REG) {
+				conf_reg = mux_reg;
+			} else {
+				conf_reg = pin_data[j++];
+				if (!(info->flags & ZERO_OFFSET_VALID) &&
+				    !conf_reg)
+					conf_reg = -1;
+			}
 
-		input_reg = pin_data[j++];
-		mux_mode = pin_data[j++];
-		input_val = pin_data[j++];
-		config_val = pin_data[j++];
+			if ((mux_reg == -1) || (conf_reg == -1)) {
+				dev_err(dev, "Error mux_reg or conf_reg\n");
+				devm_kfree(dev, pin_data);
+				return -EINVAL;
+			}
 
-		dev_dbg(dev, "mux_reg 0x%x, conf_reg 0x%x, input_reg 0x%x, "
-			"mux_mode 0x%x, input_val 0x%x, config_val 0x%x\n",
-			mux_reg, conf_reg, input_reg, mux_mode, input_val,
-			config_val);
+			input_reg = pin_data[j++];
+			mux_mode = pin_data[j++];
+			input_val = pin_data[j++];
+			config_val = pin_data[j++];
 
-		if (config_val & IMX_PAD_SION)
-			mux_mode |= IOMUXC_CONFIG_SION;
+			dev_dbg(dev, "mux_reg 0x%x, conf_reg 0x%x, "
+				"input_reg 0x%x, mux_mode 0x%x, "
+				"input_val 0x%x, config_val 0x%x\n",
+				mux_reg, conf_reg, input_reg, mux_mode,
+				input_val, config_val);
 
-		config_val &= ~IMX_PAD_SION;
+			if (config_val & IMX_PAD_SION)
+				mux_mode |= IOMUXC_CONFIG_SION;
 
-		/* Set Mux */
-		if (info->flags & SHARE_MUX_CONF_REG) {
-			clrsetbits_le32(info->base + mux_reg, info->mux_mask,
-					mux_mode << mux_shift);
-		} else {
-			writel(mux_mode, info->base + mux_reg);
-		}
+			config_val &= ~IMX_PAD_SION;
 
-		dev_dbg(dev, "write mux: offset 0x%x val 0x%x\n", mux_reg,
-			mux_mode);
+			/* Set Mux */
+			if (info->flags & SHARE_MUX_CONF_REG) {
+				clrsetbits_le32(info->base + mux_reg,
+						info->mux_mask,
+						mux_mode << mux_shift);
+			} else {
+				writel(mux_mode, info->base + mux_reg);
+			}
 
-		/*
-		 * Set select input
-		 *
-		 * If the select input value begins with 0xff, it's a quirky
-		 * select input and the value should be interpreted as below.
-		 *     31     23      15      7        0
-		 *     | 0xff | shift | width | select |
-		 * It's used to work around the problem that the select
-		 * input for some pin is not implemented in the select
-		 * input register but in some general purpose register.
-		 * We encode the select input value, width and shift of
-		 * the bit field into input_val cell of pin function ID
-		 * in device tree, and then decode them here for setting
-		 * up the select input bits in general purpose register.
-		 */
+			dev_dbg(dev, "write mux: offset 0x%x val 0x%x\n",
+				mux_reg, mux_mode);
 
-		if (input_val >> 24 == 0xff) {
-			u32 val = input_val;
-			u8 select = val & 0xff;
-			u8 width = (val >> 8) & 0xff;
-			u8 shift = (val >> 16) & 0xff;
-			u32 mask = ((1 << width) - 1) << shift;
-			/*
-			 * The input_reg[i] here is actually some IOMUXC general
-			 * purpose register, not regular select input register.
-			 */
-			val = readl(info->base + input_reg);
-			val &= ~mask;
-			val |= select << shift;
-			writel(val, info->base + input_reg);
-		} else if (input_reg) {
 			/*
-			 * Regular select input register can never be at offset
-			 * 0, and we only print register value for regular case.
+			 * Set select input
+			 *
+			 * If the select input value begins with 0xff,
+			 * it's a quirky select input and the value should
+			 * be interpreted as below.
+			 *     31     23      15      7        0
+			 *     | 0xff | shift | width | select |
+			 * It's used to work around the problem that the
+			 * select input for some pin is not implemented in
+			 * the select input register but in some general
+			 * purpose register. We encode the select input
+			 * value, width and shift of the bit field into
+			 * input_val cell of pin function ID in device tree,
+			 * and then decode them here for setting up the select
+			 * input bits in general purpose register.
 			 */
-			if (info->input_sel_base)
-				writel(input_val, info->input_sel_base +
-				       input_reg);
-			else
-				writel(input_val, info->base + input_reg);
 
-			dev_dbg(dev, "select_input: offset 0x%x val 0x%x\n",
-				input_reg, input_val);
-		}
+			if (input_val >> 24 == 0xff) {
+				u32 val = input_val;
+				u8 select = val & 0xff;
+				u8 width = (val >> 8) & 0xff;
+				u8 shift = (val >> 16) & 0xff;
+				u32 mask = ((1 << width) - 1) << shift;
+				/*
+				 * The input_reg[i] here is actually some
+				 * IOMUXC general purpose register, not
+				 * regular select input register.
+				 */
+				val = readl(info->base + input_reg);
+				val &= ~mask;
+				val |= select << shift;
+				writel(val, info->base + input_reg);
+			} else if (input_reg) {
+				/*
+				 * Regular select input register can never be
+				 * at offset 0, and we only print register
+				 * value for regular case.
+				 */
+				if (info->input_sel_base)
+					writel(input_val,
+					       info->input_sel_base +
+					       input_reg);
+				else
+					writel(input_val,
+					       info->base + input_reg);
 
-		/* Set config */
-		if (!(config_val & IMX_NO_PAD_CTL)) {
-			if (info->flags & SHARE_MUX_CONF_REG) {
-				clrsetbits_le32(info->base + conf_reg,
-						~info->mux_mask, config_val);
-			} else {
-				writel(config_val, info->base + conf_reg);
+				dev_dbg(dev, "select_input: offset 0x%x val "
+					"0x%x\n", input_reg, input_val);
 			}
 
-			dev_dbg(dev, "write config: offset 0x%x val 0x%x\n",
-				conf_reg, config_val);
+			/* Set config */
+			if (!(config_val & IMX_NO_PAD_CTL)) {
+				if (info->flags & SHARE_MUX_CONF_REG) {
+					clrsetbits_le32(info->base + conf_reg,
+							~info->mux_mask,
+							config_val);
+				} else {
+					writel(config_val,
+					       info->base + conf_reg);
+				}
+
+				dev_dbg(dev, "write config: offset 0x%x val "
+					"0x%x\n", conf_reg, config_val);
+			}
 		}
 	}
 
@@ -193,6 +210,9 @@
 	priv->dev = dev;
 	priv->info = info;
 
+	if (info->flags & IMX8_USE_SCU)
+		return 0;
+
 	addr = fdtdec_get_addr_size(gd->fdt_blob, dev_of_offset(dev), "reg",
 				    &size);
 
@@ -238,6 +258,9 @@
 	struct imx_pinctrl_priv *priv = dev_get_priv(dev);
 	struct imx_pinctrl_soc_info *info = priv->info;
 
+	if (info->flags & IMX8_USE_SCU)
+		return 0;
+
 	if (info->input_sel_base)
 		unmap_sysmem(info->input_sel_base);
 	if (info->base)