[RFC PATCH v1 1/6] rockchip: rockchip: add new clock-type for the ddrclk

Lin Huang
2016-06-03T09:55:14Z

On new rockchip platform(rk3399 etc), there have dcf controller to
do ddr frequency scaling, and this controller will implement in
arm-trust-firmware. We add a special clock-type to handle that.

Signed-off-by: Lin Huang <hl@rock-chips.com>
---
Changes in v1:
- None

drivers/clk/rockchip/Makefile | 1 +
drivers/clk/rockchip/clk-ddr.c | 147 +++++++++++++++++++++++++++++++++++++++++
drivers/clk/rockchip/clk.c | 9 +++
drivers/clk/rockchip/clk.h | 27 ++++++++
4 files changed, 184 insertions(+)
create mode 100644 drivers/clk/rockchip/clk-ddr.c

diff --git a/drivers/clk/rockchip/Makefile b/drivers/clk/rockchip/Makefile
index f47a2fa..b5f2c8e 100644
--- a/drivers/clk/rockchip/Makefile
+++ b/drivers/clk/rockchip/Makefile
@@ -8,6 +8,7 @@ obj-y += clk-pll.o
obj-y += clk-cpu.o
obj-y += clk-inverter.o
obj-y += clk-mmc-phase.o
+obj-y += clk-ddr.o
obj-$(CONFIG_RESET_CONTROLLER) += softrst.o

obj-y += clk-rk3036.o
diff --git a/drivers/clk/rockchip/clk-ddr.c b/drivers/clk/rockchip/clk-ddr.c
new file mode 100644
index 0000000..5b6630d
--- /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/of.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.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 mux_flag;
+ int div_shift;
+ int div_width;
+ int div_flag;
+ spinlock_t *lock;
+};
+
+#define to_rockchip_ddrclk_hw(hw) container_of(hw, struct rockchip_ddrclk, hw)
+#define val_mask(width) ((1 << (width)) - 1)
+
+static int rockchip_ddrclk_set_rate(struct clk_hw *hw, unsigned long drate,
+ unsigned long prate)
+{
+ struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
+ unsigned long flags;
+
+ spin_lock_irqsave(ddrclk->lock, flags);
+
+ /* TODO: set ddr rate in bl31 */
+
+ spin_unlock_irqrestore(ddrclk->lock, flags);
+
+ return 0;
+}
+
+static unsigned long
+rockchip_ddrclk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct rockchip_ddrclk *ddrclk = to_rockchip_ddrclk_hw(hw);
+ int val;
+
+ val = clk_readl(ddrclk->reg_base +
+ ddrclk->mux_offset) >> ddrclk->div_shift;
+ val &= val_mask(ddrclk->div_width);
+
+ return DIV_ROUND_UP_ULL((u64)parent_rate, val + 1);
+}
+
+static long clk_ddrclk_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *prate)
+{
+ return rate;
+}
+
+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 &= val_mask(ddrclk->mux_width);
+
+ if (val >= num_parents)
+ return -EINVAL;
+
+ return val;
+}
+
+static const struct clk_ops rockchip_ddrclk_ops = {
+ .recalc_rate = rockchip_ddrclk_recalc_rate,
+ .set_rate = rockchip_ddrclk_set_rate,
+ .round_rate = clk_ddrclk_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 mux_flag, int div_shift,
+ int div_width, int div_flag,
+ void __iomem *reg_base,
+ spinlock_t *lock)
+{
+ struct rockchip_ddrclk *ddrclk;
+ struct clk_init_data init;
+ struct clk *clk;
+ int ret;
+
+ 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.ops = &rockchip_ddrclk_ops;
+
+ init.flags = flags;
+ init.flags |= CLK_SET_RATE_NO_REPARENT;
+ init.flags |= CLK_GET_RATE_NOCACHE;
+
+ 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->mux_flag = mux_flag;
+ ddrclk->div_shift = div_shift;
+ ddrclk->div_width = div_width;
+ ddrclk->div_flag = div_flag;
+
+ clk = clk_register(NULL, &ddrclk->hw);
+ if (IS_ERR(clk)) {
+ pr_err("%s: could not register ddrclk %s\n", __func__, name);
+ ret = PTR_ERR(clk);
+ goto free_ddrclk;
+ }
+
+ return clk;
+
+free_ddrclk:
+ kfree(ddrclk);
+ return ERR_PTR(ret);
+}
diff --git a/drivers/clk/rockchip/clk.c b/drivers/clk/rockchip/clk.c
index 7ffd134..6ac1aa5 100644
--- a/drivers/clk/rockchip/clk.c
+++ b/drivers/clk/rockchip/clk.c
@@ -484,6 +484,15 @@ void __init rockchip_clk_register_branches(
list->gate_offset, list->gate_shift,
list->gate_flags, flags, &ctx->lock);
break;
+ case branch_ddrc:
+ clk = rockchip_clk_register_ddrclk(
+ list->name, list->flags,
+ list->parent_names, list->num_parents,
+ list->muxdiv_offset, list->mux_shift,
+ list->mux_width, list->mux_flags,
+ list->div_shift, list->div_width,
+ list->div_flags, ctx->reg_base, &ctx->lock);
+ break;
}

/* none of the cases above matched */
diff --git a/drivers/clk/rockchip/clk.h b/drivers/clk/rockchip/clk.h
index 2194ffa..4033fe4 100644
--- a/drivers/clk/rockchip/clk.h
+++ b/drivers/clk/rockchip/clk.h
@@ -281,6 +281,13 @@ struct clk *rockchip_clk_register_mmc(const char *name,
const char *const *parent_names, u8 num_parents,
void __iomem *reg, int shift);

+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 mux_flag, int div_shift, int div_width,
+ int div_flag, void __iomem *reg_base,
+ spinlock_t *lock);
+
#define ROCKCHIP_INVERTER_HIWORD_MASK BIT(0)

struct clk *rockchip_clk_register_inverter(const char *name,
@@ -299,6 +306,7 @@ enum rockchip_clk_branch_type {
branch_mmc,
branch_inverter,
branch_factor,
+ branch_ddrc,
};

struct rockchip_clk_branch {
@@ -488,6 +496,25 @@ struct rockchip_clk_branch {
.child = ch, \
}

+#define COMPOSITE_DDRC(_id, cname, pnames, f, mo, ms, mw, mf, \
+ ds, dw, df) \
+ { \
+ .id = _id, \
+ .branch_type = branch_ddrc, \
+ .name = cname, \
+ .parent_names = pnames, \
+ .num_parents = ARRAY_SIZE(pnames), \
+ .flags = f, \
+ .muxdiv_offset = mo, \
+ .mux_shift = ms, \
+ .mux_width = mw, \
+ .mux_flags = mf, \
+ .div_shift = ds, \
+ .div_width = dw, \
+ .div_flags = df, \
+ .gate_offset = -1, \
+ }
+
#define MUX(_id, cname, pnames, f, o, s, w, mf) \
{ \
.id = _id, \
--
1.9.1