Re: [PATCH v9 1/4] clk: meson: add one based divider support for sclk divider
From: Jerome Brunet <jbrunet@baylibre.com>
Date: 2019-01-22 09:25:24
Also in:
linux-amlogic, linux-clk, linux-devicetree, lkml
On Tue, 2019-01-08 at 21:50 +0800, Jianxin Pan wrote:
quoted hunk ↗ jump to hunk
When CLK_DIVIDER_ONE_BASED flag is set, the sclk divider will be: one based divider (div = val), and zero value gates the clock Signed-off-by: Jianxin Pan <redacted> --- drivers/clk/meson/Makefile | 3 ++- drivers/clk/meson/clkc-audio.h | 8 ------ drivers/clk/meson/clkc.h | 10 ++++++- drivers/clk/meson/sclk-div.c | 59 ++++++++++++++++++++++++++++----------- --- 4 files changed, 50 insertions(+), 30 deletions(-)diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile index a849aa8..acd8694 100644 --- a/drivers/clk/meson/Makefile +++ b/drivers/clk/meson/Makefile@@ -4,7 +4,8 @@ obj-$(CONFIG_COMMON_CLK_AMLOGIC) += clk-pll.o clk-mpll.o clk-phase.o vid-pll-div.o obj-$(CONFIG_COMMON_CLK_AMLOGIC) += clk-input.o -obj-$(CONFIG_COMMON_CLK_AMLOGIC_AUDIO) += clk-triphase.o sclk-div.o +obj-$(CONFIG_COMMON_CLK_AMLOGIC) += sclk-div.o +obj-$(CONFIG_COMMON_CLK_AMLOGIC_AUDIO) += clk-triphase.o obj-$(CONFIG_COMMON_CLK_MESON_AO) += meson-aoclk.o obj-$(CONFIG_COMMON_CLK_MESON8B) += meson8b.o obj-$(CONFIG_COMMON_CLK_GXBB) += gxbb.o gxbb-aoclk.o gxbb-aoclk- 32k.odiff --git a/drivers/clk/meson/clkc-audio.h b/drivers/clk/meson/clkc-audio.h index 0a7c157..286ff12 100644 --- a/drivers/clk/meson/clkc-audio.h +++ b/drivers/clk/meson/clkc-audio.h@@ -15,14 +15,6 @@ struct meson_clk_triphase_data { struct parm ph2; }; -struct meson_sclk_div_data { - struct parm div; - struct parm hi; - unsigned int cached_div; - struct clk_duty cached_duty; -}; - extern const struct clk_ops meson_clk_triphase_ops; -extern const struct clk_ops meson_sclk_div_ops; #endif /* __MESON_CLKC_AUDIO_H */diff --git a/drivers/clk/meson/clkc.h b/drivers/clk/meson/clkc.h index 6183b22..00b3320 100644 --- a/drivers/clk/meson/clkc.h +++ b/drivers/clk/meson/clkc.h@@ -27,6 +27,14 @@ struct parm { u8 width; }; +struct meson_sclk_div_data { + struct parm div; + struct parm hi; + unsigned int cached_div; + struct clk_duty cached_duty; + u8 flags; +}; + static inline unsigned int meson_parm_read(struct regmap *map, struct parm*p) { unsigned int val;@@ -118,10 +126,10 @@ struct clk_regmap _name = {\ extern const struct clk_ops meson_clk_mpll_ops; extern const struct clk_ops meson_clk_phase_ops; extern const struct clk_ops meson_vid_pll_div_ro_ops; +extern const struct clk_ops meson_sclk_div_ops; struct clk_hw *meson_clk_hw_register_input(struct device *dev, const char *of_name, const char *clk_name, unsigned long flags); - #endif /* __CLKC_H */diff --git a/drivers/clk/meson/sclk-div.c b/drivers/clk/meson/sclk-div.c index bc64019..a6c425b 100644 --- a/drivers/clk/meson/sclk-div.c +++ b/drivers/clk/meson/sclk-div.c@@ -4,42 +4,60 @@ * Author: Jerome Brunet <jbrunet@baylibre.com> * * Sample clock generator divider: - * This HW divider gates with value 0 but is otherwise a zero baseddivider: + * This HW divider gates with value 0 * * val >= 1 - * divider = val + 1 + * divider = val + 1 if ONE_BASED is not set, otherwise divider = val. * * The duty cycle may also be set for the LR clock variant. The duty cycle * ratio is: * * hi = [0 - val] - * duty_cycle = (1 + hi) / (1 + val) + * duty_cycle = (1 + hi) / (1 + val) if ONE_BASED is not set, otherwise: + * duty_cycle = hi / (1 + val) */ -#include "clkc-audio.h" +#include "clkc.h" -static inline struct meson_sclk_div_data * -meson_sclk_div_data(struct clk_regmap *clk) +static inline int get_reg(int val, unsigned char flag)
s/get_reg/sclk_get_reg
{
- return (struct meson_sclk_div_data *)clk->data;
+ WARN_ON(val < 1);I don't think this WARN is justified, especially since you are using this function to set the hi value.
+ if ((flag & CLK_DIVIDER_ONE_BASED) || !val)
I don't like that you make a dependency on the generic divider just for this. Please make your own flag like MESON_SCLK_ONE_BASED
+ return val; + else + return val - 1; +} + +static inline int get_value(int reg, unsigned char flag)
s/get_value/sclk_get_divider
+{
+ if (flag & CLK_DIVIDER_ONE_BASED)
+ return reg;
+ else
+ return reg + 1;
}
-static int sclk_div_maxval(struct meson_sclk_div_data *sclk)
+static inline struct meson_sclk_div_data *
+meson_sclk_div_data(struct clk_regmap *clk)
{
- return (1 << sclk->div.width) - 1;
+ return (struct meson_sclk_div_data *)clk->data;
}
static int sclk_div_maxdiv(struct meson_sclk_div_data *sclk)
{
- return sclk_div_maxval(sclk) + 1;
+ unsigned int reg = clk_div_mask(sclk->div.width);same here, leave the generic divider alone. `(1 << sclk->div.width) - 1` was fine to get max register value.
+
+ return get_value(reg, sclk->flags);
}
static int sclk_div_getdiv(struct clk_hw *hw, unsigned long rate,
unsigned long prate, int maxdiv)
{
int div = DIV_ROUND_CLOSEST_ULL((u64)prate, rate);
+ struct clk_regmap *clk = to_clk_regmap(hw);
+ struct meson_sclk_div_data *sclk = meson_sclk_div_data(clk);
+ int mindiv = get_value(1, sclk->flags);maxdiv is provided as a param while mindiv is computed inside this function. let's be coherent and pick one approach.
quoted hunk ↗ jump to hunk
- return clamp(div, 2, maxdiv); + return clamp(div, mindiv, maxdiv); } static int sclk_div_bestdiv(struct clk_hw *hw, unsigned long rate,@@ -47,7 +65,7 @@ static int sclk_div_bestdiv(struct clk_hw *hw, unsignedlong rate, struct meson_sclk_div_data *sclk) { struct clk_hw *parent = clk_hw_get_parent(hw); - int bestdiv = 0, i; + int bestdiv = 0, i, mindiv; unsigned long maxdiv, now, parent_now; unsigned long best = 0, best_parent = 0;@@ -64,8 +82,9 @@ static int sclk_div_bestdiv(struct clk_hw *hw, unsignedlong rate, * unsigned long in rate * i below */ maxdiv = min(ULONG_MAX / rate, maxdiv); + mindiv = get_value(1, sclk->flags); - for (i = 2; i <= maxdiv; i++) { + for (i = mindiv; i <= maxdiv; i++) { /* * It's the most ideal case if the requested rate can be * divided from parent clock without needing to change@@ -111,10 +130,7 @@ static void sclk_apply_ratio(struct clk_regmap *clk, sclk->cached_duty.num, sclk->cached_duty.den); - if (hi) - hi -= 1; - - meson_parm_write(clk->map, &sclk->hi, hi); + meson_parm_write(clk->map, &sclk->hi, get_reg(hi, sclk->flags)); } static int sclk_div_set_duty_cycle(struct clk_hw *hw,@@ -145,7 +161,7 @@ static int sclk_div_get_duty_cycle(struct clk_hw *hw, } hi = meson_parm_read(clk->map, &sclk->hi); - duty->num = hi + 1; + duty->num = get_value(hi, sclk->flags); duty->den = sclk->cached_div; return 0; }@@ -153,10 +169,13 @@ static int sclk_div_get_duty_cycle(struct clk_hw *hw, static void sclk_apply_divider(struct clk_regmap *clk, struct meson_sclk_div_data *sclk) { + unsigned int div; + if (MESON_PARM_APPLICABLE(&sclk->hi)) sclk_apply_ratio(clk, sclk); - meson_parm_write(clk->map, &sclk->div, sclk->cached_div - 1); + div = get_reg(sclk->cached_div, sclk->flags); + meson_parm_write(clk->map, &sclk->div, div); } static int sclk_div_set_rate(struct clk_hw *hw, unsigned long rate,@@ -224,7 +243,7 @@ static void sclk_div_init(struct clk_hw *hw) if (!val) sclk->cached_div = sclk_div_maxdiv(sclk); else - sclk->cached_div = val + 1; + sclk->cached_div = get_value(val, sclk->flags); sclk_div_get_duty_cycle(hw, &sclk->cached_duty); }
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