[PATCH 1/5] clk: sunxi-ng: Add maximum rate constraint to NM PLLs

From: Jernej Skrabec
Date: Thu Aug 09 2018 - 12:52:37 EST


On some NM PLLs, frequency can be set above PLL working range.

Add a constraint for maximum supported rate. This way, drivers can
specify which is maximum allowed rate for PLL.

Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
---
drivers/clk/sunxi-ng/ccu_nm.c | 7 +++++++
drivers/clk/sunxi-ng/ccu_nm.h | 30 ++++++++++++++++++++++++++++++
2 files changed, 37 insertions(+)

diff --git a/drivers/clk/sunxi-ng/ccu_nm.c b/drivers/clk/sunxi-ng/ccu_nm.c
index 4e2073307f34..6fe3c14f7b2d 100644
--- a/drivers/clk/sunxi-ng/ccu_nm.c
+++ b/drivers/clk/sunxi-ng/ccu_nm.c
@@ -124,6 +124,13 @@ static long ccu_nm_round_rate(struct clk_hw *hw, unsigned long rate,
return rate;
}

+ if (nm->max_rate && rate > nm->max_rate) {
+ rate = nm->max_rate;
+ if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate /= nm->fixed_post_div;
+ return rate;
+ }
+
if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) {
if (nm->common.features & CCU_FEATURE_FIXED_POSTDIV)
rate /= nm->fixed_post_div;
diff --git a/drivers/clk/sunxi-ng/ccu_nm.h b/drivers/clk/sunxi-ng/ccu_nm.h
index 1d8b459c50b7..de232f2199a6 100644
--- a/drivers/clk/sunxi-ng/ccu_nm.h
+++ b/drivers/clk/sunxi-ng/ccu_nm.h
@@ -38,6 +38,7 @@ struct ccu_nm {

unsigned int fixed_post_div;
unsigned int min_rate;
+ unsigned int max_rate;

struct ccu_common common;
};
@@ -115,6 +116,35 @@ struct ccu_nm {
}, \
}

+#define SUNXI_CCU_NM_WITH_FRAC_GATE_LOCK_MIN_MAX(_struct, _name, \
+ _parent, _reg, \
+ _min_rate, _max_rate, \
+ _nshift, _nwidth, \
+ _mshift, _mwidth, \
+ _frac_en, _frac_sel, \
+ _frac_rate_0, \
+ _frac_rate_1, \
+ _gate, _lock, _flags) \
+ struct ccu_nm _struct = { \
+ .enable = _gate, \
+ .lock = _lock, \
+ .n = _SUNXI_CCU_MULT(_nshift, _nwidth), \
+ .m = _SUNXI_CCU_DIV(_mshift, _mwidth), \
+ .frac = _SUNXI_CCU_FRAC(_frac_en, _frac_sel, \
+ _frac_rate_0, \
+ _frac_rate_1), \
+ .min_rate = _min_rate, \
+ .max_rate = _max_rate, \
+ .common = { \
+ .reg = _reg, \
+ .features = CCU_FEATURE_FRACTIONAL, \
+ .hw.init = CLK_HW_INIT(_name, \
+ _parent, \
+ &ccu_nm_ops, \
+ _flags), \
+ }, \
+ }
+
#define SUNXI_CCU_NM_WITH_GATE_LOCK(_struct, _name, _parent, _reg, \
_nshift, _nwidth, \
_mshift, _mwidth, \
--
2.18.0