ARMv8/PSCI: Fixup the device tree for PSCI

Set the enable-method in the cpu node to PSCI, and create device
node for PSCI, when PSCI was enabled.

Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
diff --git a/arch/arm/lib/psci-dt.c b/arch/arm/lib/psci-dt.c
new file mode 100644
index 0000000..8dc31d4
--- /dev/null
+++ b/arch/arm/lib/psci-dt.c
@@ -0,0 +1,123 @@
+/*
+ * Copyright 2016 NXP Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <libfdt.h>
+#include <fdt_support.h>
+#include <linux/sizes.h>
+#include <linux/kernel.h>
+#include <asm/psci.h>
+#ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
+#include <asm/armv8/sec_firmware.h>
+#endif
+
+int fdt_psci(void *fdt)
+{
+#if defined(CONFIG_ARMV8_PSCI) || defined(CONFIG_ARMV7_PSCI)
+	int nodeoff;
+	unsigned int psci_ver = 0;
+	char *psci_compt;
+	int tmp;
+
+	nodeoff = fdt_path_offset(fdt, "/cpus");
+	if (nodeoff < 0) {
+		printf("couldn't find /cpus\n");
+		return nodeoff;
+	}
+
+	/* add 'enable-method = "psci"' to each cpu node */
+	for (tmp = fdt_first_subnode(fdt, nodeoff);
+	     tmp >= 0;
+	     tmp = fdt_next_subnode(fdt, tmp)) {
+		const struct fdt_property *prop;
+		int len;
+
+		prop = fdt_get_property(fdt, tmp, "device_type", &len);
+		if (!prop)
+			continue;
+		if (len < 4)
+			continue;
+		if (strcmp(prop->data, "cpu"))
+			continue;
+
+		/*
+		 * Not checking rv here, our approach is to skip over errors in
+		 * individual cpu nodes, hopefully some of the nodes are
+		 * processed correctly and those will boot
+		 */
+		fdt_setprop_string(fdt, tmp, "enable-method", "psci");
+	}
+
+	/*
+	 * The PSCI node might be called "/psci" or might be called something
+	 * else but contain either of the compatible strings
+	 * "arm,psci"/"arm,psci-0.2"
+	 */
+	nodeoff = fdt_path_offset(fdt, "/psci");
+	if (nodeoff >= 0)
+		goto init_psci_node;
+
+	nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci");
+	if (nodeoff >= 0)
+		goto init_psci_node;
+
+	nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci-0.2");
+	if (nodeoff >= 0)
+		goto init_psci_node;
+
+	nodeoff = fdt_node_offset_by_compatible(fdt, -1, "arm,psci-1.0");
+	if (nodeoff >= 0)
+		goto init_psci_node;
+
+	nodeoff = fdt_path_offset(fdt, "/");
+	if (nodeoff < 0)
+		return nodeoff;
+
+	nodeoff = fdt_add_subnode(fdt, nodeoff, "psci");
+	if (nodeoff < 0)
+		return nodeoff;
+
+init_psci_node:
+#ifdef CONFIG_ARMV8_SEC_FIRMWARE_SUPPORT
+	psci_ver = sec_firmware_support_psci_version();
+#endif
+	switch (psci_ver) {
+	case 0x00010000:
+		psci_compt = "arm,psci-1.0";
+		break;
+	case 0x00000002:
+		psci_compt = "arm,psci-0.2";
+		break;
+	default:
+		psci_compt = "arm,psci";
+		break;
+	}
+
+	tmp = fdt_setprop_string(fdt, nodeoff, "compatible", psci_compt);
+	if (tmp)
+		return tmp;
+	tmp = fdt_setprop_string(fdt, nodeoff, "method", "smc");
+	if (tmp)
+		return tmp;
+
+#ifdef CONFIG_ARMV7_PSCI
+	tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_suspend",
+				ARM_PSCI_FN_CPU_SUSPEND);
+	if (tmp)
+		return tmp;
+	tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_off", ARM_PSCI_FN_CPU_OFF);
+	if (tmp)
+		return tmp;
+	tmp = fdt_setprop_u32(fdt, nodeoff, "cpu_on", ARM_PSCI_FN_CPU_ON);
+	if (tmp)
+		return tmp;
+	tmp = fdt_setprop_u32(fdt, nodeoff, "migrate", ARM_PSCI_FN_MIGRATE);
+	if (tmp)
+		return tmp;
+#endif
+#endif
+	return 0;
+}