v4.19.13 snapshot.
diff --git a/drivers/clk/rockchip/clk-ddr.c b/drivers/clk/rockchip/clk-ddr.c
new file mode 100644
index 0000000..ebce526
--- /dev/null
+++ b/drivers/clk/rockchip/clk-ddr.c
@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) 2016 Rockchip Electronics Co. Ltd.
+ * Author: Lin Huang <hl@rock-chips.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/arm-smccc.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <soc/rockchip/rockchip_sip.h>
+#include "clk.h"
+
+struct rockchip_ddrclk {
+	struct clk_hw	hw;
+	void __iomem	*reg_base;
+	int		mux_offset;
+	int		mux_shift;
+	int		mux_width;
+	int		div_shift;
+	int		div_width;
+	int		ddr_flag;
+	spinlock_t	*lock;
+};
+
+#define to_rockchip_ddrclk_hw(hw) container_of(hw, struct rockchip_ddrclk, hw)
+
+static int rockchip_ddrclk_sip_set_rate(struct clk_hw *hw, unsigned long drate,
+					unsigned long prate)
+{
+	struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
+	unsigned long flags;
+	struct arm_smccc_res res;
+
+	spin_lock_irqsave(ddrclk->lock, flags);
+	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, drate, 0,
+		      ROCKCHIP_SIP_CONFIG_DRAM_SET_RATE,
+		      0, 0, 0, 0, &res);
+	spin_unlock_irqrestore(ddrclk->lock, flags);
+
+	return res.a0;
+}
+
+static unsigned long
+rockchip_ddrclk_sip_recalc_rate(struct clk_hw *hw,
+				unsigned long parent_rate)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
+		      ROCKCHIP_SIP_CONFIG_DRAM_GET_RATE,
+		      0, 0, 0, 0, &res);
+
+	return res.a0;
+}
+
+static long rockchip_ddrclk_sip_round_rate(struct clk_hw *hw,
+					   unsigned long rate,
+					   unsigned long *prate)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, rate, 0,
+		      ROCKCHIP_SIP_CONFIG_DRAM_ROUND_RATE,
+		      0, 0, 0, 0, &res);
+
+	return res.a0;
+}
+
+static u8 rockchip_ddrclk_get_parent(struct clk_hw *hw)
+{
+	struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
+	u32 val;
+
+	val = clk_readl(ddrclk->reg_base +
+			ddrclk->mux_offset) >> ddrclk->mux_shift;
+	val &= GENMASK(ddrclk->mux_width - 1, 0);
+
+	return val;
+}
+
+static const struct clk_ops rockchip_ddrclk_sip_ops = {
+	.recalc_rate = rockchip_ddrclk_sip_recalc_rate,
+	.set_rate = rockchip_ddrclk_sip_set_rate,
+	.round_rate = rockchip_ddrclk_sip_round_rate,
+	.get_parent = rockchip_ddrclk_get_parent,
+};
+
+struct clk *rockchip_clk_register_ddrclk(const char *name, int flags,
+					 const char *const *parent_names,
+					 u8 num_parents, int mux_offset,
+					 int mux_shift, int mux_width,
+					 int div_shift, int div_width,
+					 int ddr_flag, void __iomem *reg_base,
+					 spinlock_t *lock)
+{
+	struct rockchip_ddrclk *ddrclk;
+	struct clk_init_data init;
+	struct clk *clk;
+
+	ddrclk = kzalloc(sizeof(*ddrclk), GFP_KERNEL);
+	if (!ddrclk)
+		return ERR_PTR(-ENOMEM);
+
+	init.name = name;
+	init.parent_names = parent_names;
+	init.num_parents = num_parents;
+
+	init.flags = flags;
+	init.flags |= CLK_SET_RATE_NO_REPARENT;
+
+	switch (ddr_flag) {
+	case ROCKCHIP_DDRCLK_SIP:
+		init.ops = &rockchip_ddrclk_sip_ops;
+		break;
+	default:
+		pr_err("%s: unsupported ddrclk type %d\n", __func__, ddr_flag);
+		kfree(ddrclk);
+		return ERR_PTR(-EINVAL);
+	}
+
+	ddrclk->reg_base = reg_base;
+	ddrclk->lock = lock;
+	ddrclk->hw.init = &init;
+	ddrclk->mux_offset = mux_offset;
+	ddrclk->mux_shift = mux_shift;
+	ddrclk->mux_width = mux_width;
+	ddrclk->div_shift = div_shift;
+	ddrclk->div_width = div_width;
+	ddrclk->ddr_flag = ddr_flag;
+
+	clk = clk_register(NULL, &ddrclk->hw);
+	if (IS_ERR(clk))
+		kfree(ddrclk);
+
+	return clk;
+}