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

source/bootloader/u-boot-2020.01/drivers/clk/imx/clk-gate2.c

@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 DENX Software Engineering
+ * Lukasz Majewski, DENX Software Engineering, lukma@denx.de
+ *
+ * Copyright (C) 2010-2011 Canonical Ltd <jeremy.kerr@canonical.com>
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd <mturquette@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Gated clock implementation
+ *
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <malloc.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <linux/clk-provider.h>
+#include <clk.h>
+#include "clk.h"
+
+#define UBOOT_DM_CLK_IMX_GATE2 "imx_clk_gate2"
+
+struct clk_gate2 {
+	struct clk clk;
+	void __iomem	*reg;
+	u8		bit_idx;
+	u8		cgr_val;
+	u8		flags;
+};
+
+#define to_clk_gate2(_clk) container_of(_clk, struct clk_gate2, clk)
+
+static int clk_gate2_enable(struct clk *clk)
+{
+	struct clk_gate2 *gate = to_clk_gate2(dev_get_clk_ptr(clk->dev));
+	u32 reg;
+
+	reg = readl(gate->reg);
+	reg &= ~(3 << gate->bit_idx);
+	reg |= gate->cgr_val << gate->bit_idx;
+	writel(reg, gate->reg);
+
+	return 0;
+}
+
+static int clk_gate2_disable(struct clk *clk)
+{
+	struct clk_gate2 *gate = to_clk_gate2(dev_get_clk_ptr(clk->dev));
+	u32 reg;
+
+	reg = readl(gate->reg);
+	reg &= ~(3 << gate->bit_idx);
+	writel(reg, gate->reg);
+
+	return 0;
+}
+
+static ulong clk_gate2_set_rate(struct clk *clk, ulong rate)
+{
+	struct clk *parent = clk_get_parent(clk);
+
+	if (parent)
+		return clk_set_rate(parent, rate);
+
+	return -ENODEV;
+}
+
+static const struct clk_ops clk_gate2_ops = {
+	.set_rate = clk_gate2_set_rate,
+	.enable = clk_gate2_enable,
+	.disable = clk_gate2_disable,
+	.get_rate = clk_generic_get_rate,
+};
+
+struct clk *clk_register_gate2(struct device *dev, const char *name,
+		const char *parent_name, unsigned long flags,
+		void __iomem *reg, u8 bit_idx, u8 cgr_val,
+		u8 clk_gate2_flags)
+{
+	struct clk_gate2 *gate;
+	struct clk *clk;
+	int ret;
+
+	gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+	if (!gate)
+		return ERR_PTR(-ENOMEM);
+
+	gate->reg = reg;
+	gate->bit_idx = bit_idx;
+	gate->cgr_val = cgr_val;
+	gate->flags = clk_gate2_flags;
+
+	clk = &gate->clk;
+
+	ret = clk_register(clk, UBOOT_DM_CLK_IMX_GATE2, name, parent_name);
+	if (ret) {
+		kfree(gate);
+		return ERR_PTR(ret);
+	}
+
+	return clk;
+}
+
+U_BOOT_DRIVER(clk_gate2) = {
+	.name	= UBOOT_DM_CLK_IMX_GATE2,
+	.id	= UCLASS_CLK,
+	.ops	= &clk_gate2_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};