Hi Heiko,
On 2016年06月03日 20:51, Heiko Stübner wrote:
Am Freitag, 3. Juni 2016, 17:55:14 schrieb Lin Huang:
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 <h...@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 <h...@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)
maybe use GENMASK?
Oh, yes, we can use it. Will fix next version.
+
+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 */
I expect this interface to be in existence and merged into the main ATF first.
Right now the whole clock-type does nothing more than a simple COMPOSITE with
added CLK_DIVIDER_READ_ONLY | CLK_MUX_READ_ONLY.
Also Mike is propably still working in the so called coordinated rate change
for clocks needing special handling on rate changes, which might provide a
second approach to this.
You mean there is a patch set can handle it now? Can you tell me
the ID,
I want to check it.
So please, first of all get the ATF-interface merged and meanwhile if you need
to read the clock-rate, just use a regular composite, with the read-only flags.
My colleague are wroking on ATF code now, I agree with you, We can
not merge
this patch set before ATF-interface merged. And we do not need to
add a new code
if we only want to read ddr clock rate(we can get the ddr rate to
read dpll), so i prefer
to keep this function for now, and do review first, once the ATF
code ready, we can merge
soon it(i hope :-P ) .
+ 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);
return divider_recalc_rate(...)
got it , thank you.
Heiko
--
Lin Huang
