GK SDK 源码库: XMIPCLinuxV100R005C00SPC030 (kernel/tools/open_source excluded)

source/bootloader/u-boot-2020.01/arch/arm/mach-aspeed/ast2500/clk_ast2500.c

@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2016 Google, Inc
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <asm/io.h>
+#include <asm/arch/scu_ast2500.h>
+
+int ast_get_clk(struct udevice **devp)
+{
+	return uclass_get_device_by_driver(UCLASS_CLK,
+			DM_GET_DRIVER(aspeed_ast2500_scu), devp);
+}
+
+void *ast_get_scu(void)
+{
+	struct ast2500_clk_priv *priv;
+	struct udevice *dev;
+	int ret;
+
+	ret = ast_get_clk(&dev);
+	if (ret)
+		return ERR_PTR(ret);
+
+	priv = dev_get_priv(dev);
+
+	return priv->scu;
+}
+
+void ast_scu_unlock(struct ast2500_scu *scu)
+{
+	writel(SCU_UNLOCK_VALUE, &scu->protection_key);
+	while (!readl(&scu->protection_key))
+		;
+}
+
+void ast_scu_lock(struct ast2500_scu *scu)
+{
+	writel(~SCU_UNLOCK_VALUE, &scu->protection_key);
+	while (readl(&scu->protection_key))
+		;
+}