[PATCH v4 1/3] clk: sunxi-ng: div: Add support for fixed post-divider

From: Icenowy Zheng
Date: Sat Aug 12 2017 - 08:44:59 EST


From: Priit Laes <plaes@xxxxxxxxx>

SATA clock on sun4i/sun7i is of type (parent) / M / 6 where
6 is fixed post-divider.

Signed-off-by: Priit Laes <plaes@xxxxxxxxx>
---
It's based on the patch in v6 of the A10/A20 CCU patchset, but with
ccu_div_round_rate fixed.

drivers/clk/sunxi-ng/ccu_div.c | 22 +++++++++++++++++++---
drivers/clk/sunxi-ng/ccu_div.h | 3 ++-
2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/sunxi-ng/ccu_div.c b/drivers/clk/sunxi-ng/ccu_div.c
index c0e5c10d0091..baa3cf96507b 100644
--- a/drivers/clk/sunxi-ng/ccu_div.c
+++ b/drivers/clk/sunxi-ng/ccu_div.c
@@ -21,10 +21,18 @@ static unsigned long ccu_div_round_rate(struct ccu_mux_internal *mux,
{
struct ccu_div *cd = data;

- return divider_round_rate_parent(&cd->common.hw, parent,
+ if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate *= cd->fixed_post_div;
+
+ rate = divider_round_rate_parent(&cd->common.hw, parent,
rate, parent_rate,
cd->div.table, cd->div.width,
cd->div.flags);
+
+ if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate /= cd->fixed_post_div;
+
+ return rate;
}

static void ccu_div_disable(struct clk_hw *hw)
@@ -62,8 +70,13 @@ static unsigned long ccu_div_recalc_rate(struct clk_hw *hw,
parent_rate = ccu_mux_helper_apply_prediv(&cd->common, &cd->mux, -1,
parent_rate);

- return divider_recalc_rate(hw, parent_rate, val, cd->div.table,
- cd->div.flags);
+ val = divider_recalc_rate(hw, parent_rate, val, cd->div.table,
+ cd->div.flags);
+
+ if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ val /= cd->fixed_post_div;
+
+ return val;
}

static int ccu_div_determine_rate(struct clk_hw *hw,
@@ -86,6 +99,9 @@ static int ccu_div_set_rate(struct clk_hw *hw, unsigned long rate,
parent_rate = ccu_mux_helper_apply_prediv(&cd->common, &cd->mux, -1,
parent_rate);

+ if (cd->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate *= cd->fixed_post_div;
+
val = divider_get_val(rate, parent_rate, cd->div.table, cd->div.width,
cd->div.flags);

diff --git a/drivers/clk/sunxi-ng/ccu_div.h b/drivers/clk/sunxi-ng/ccu_div.h
index 08d074451204..f3a5028dcd14 100644
--- a/drivers/clk/sunxi-ng/ccu_div.h
+++ b/drivers/clk/sunxi-ng/ccu_div.h
@@ -86,9 +86,10 @@ struct ccu_div_internal {
struct ccu_div {
u32 enable;

- struct ccu_div_internal div;
+ struct ccu_div_internal div;
struct ccu_mux_internal mux;
struct ccu_common common;
+ unsigned int fixed_post_div;
};

#define SUNXI_CCU_DIV_TABLE_WITH_GATE(_struct, _name, _parent, _reg, \
--
2.13.0