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path: root/drivers/clk/rockchip/clk-ddr.c
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-rw-r--r--drivers/clk/rockchip/clk-ddr.c154
1 files changed, 154 insertions, 0 deletions
diff --git a/drivers/clk/rockchip/clk-ddr.c b/drivers/clk/rockchip/clk-ddr.c
new file mode 100644
index 000000000000..8feba93672c5
--- /dev/null
+++ b/drivers/clk/rockchip/clk-ddr.c
@@ -0,0 +1,154 @@
+/*
+ * 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);
+ int num_parents = clk_hw_get_num_parents(hw);
+ u32 val;
+
+ val = clk_readl(ddrclk->reg_base +
+ ddrclk->mux_offset) >> ddrclk->mux_shift;
+ val &= GENMASK(ddrclk->mux_width - 1, 0);
+
+ if (val >= num_parents)
+ return -EINVAL;
+
+ 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)) {
+ pr_err("%s: could not register ddrclk %s\n", __func__, name);
+ kfree(ddrclk);
+ return NULL;
+ }
+
+ return clk;
+}