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

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

@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 DENX Software Engineering
+ * Lukasz Majewski, DENX Software Engineering, lukma@denx.de
+ *
+ * Copyright 2012 Freescale Semiconductor, Inc.
+ * Copyright 2012 Linaro Ltd.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <malloc.h>
+#include <clk-uclass.h>
+#include <dm/device.h>
+#include <linux/clk-provider.h>
+#include <div64.h>
+#include <clk.h>
+#include "clk.h"
+
+#define UBOOT_DM_CLK_IMX_PFD "imx_clk_pfd"
+
+struct clk_pfd {
+	struct clk	clk;
+	void __iomem	*reg;
+	u8		idx;
+};
+
+#define to_clk_pfd(_clk) container_of(_clk, struct clk_pfd, clk)
+
+#define SET	0x4
+#define CLR	0x8
+#define OTG	0xc
+
+static unsigned long clk_pfd_recalc_rate(struct clk *clk)
+{
+	struct clk_pfd *pfd =
+		to_clk_pfd(dev_get_clk_ptr(clk->dev));
+	unsigned long parent_rate = clk_get_parent_rate(clk);
+	u64 tmp = parent_rate;
+	u8 frac = (readl(pfd->reg) >> (pfd->idx * 8)) & 0x3f;
+
+	tmp *= 18;
+	do_div(tmp, frac);
+
+	return tmp;
+}
+
+static const struct clk_ops clk_pfd_ops = {
+	.get_rate	= clk_pfd_recalc_rate,
+};
+
+struct clk *imx_clk_pfd(const char *name, const char *parent_name,
+			void __iomem *reg, u8 idx)
+{
+	struct clk_pfd *pfd;
+	struct clk *clk;
+	int ret;
+
+	pfd = kzalloc(sizeof(*pfd), GFP_KERNEL);
+	if (!pfd)
+		return ERR_PTR(-ENOMEM);
+
+	pfd->reg = reg;
+	pfd->idx = idx;
+
+	/* register the clock */
+	clk = &pfd->clk;
+
+	ret = clk_register(clk, UBOOT_DM_CLK_IMX_PFD, name, parent_name);
+	if (ret) {
+		kfree(pfd);
+		return ERR_PTR(ret);
+	}
+
+	return clk;
+}
+
+U_BOOT_DRIVER(clk_pfd) = {
+	.name	= UBOOT_DM_CLK_IMX_PFD,
+	.id	= UCLASS_CLK,
+	.ops	= &clk_pfd_ops,
+	.flags = DM_FLAG_PRE_RELOC,
+};