Some NKM 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: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
Acked-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Tested-by: Jagan Teki <jagan@xxxxxxxxxxxxxxxxxxxx>
---
Changes for v3:
- collect Stephen Ack
- add tested credit
Changes for v2:
- none
drivers/clk/sunxi-ng/ccu_nkm.c | 7 +++++++
drivers/clk/sunxi-ng/ccu_nkm.h | 1 +
2 files changed, 8 insertions(+)
diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c
index d17539dc88dd..574fd2cd2a79 100644
--- a/drivers/clk/sunxi-ng/ccu_nkm.c
+++ b/drivers/clk/sunxi-ng/ccu_nkm.c
@@ -132,6 +132,13 @@ static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux,
return rate;
}
+ if (nkm->max_rate && rate > nkm->max_rate) {
+ rate = nkm->max_rate;
+ if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate /= nkm->fixed_post_div;
+ return rate;
+ }
+
ccu_nkm_find_best(*parent_rate, rate, &_nkm);
rate = *parent_rate * _nkm.n * _nkm.k / _nkm.m;
diff --git a/drivers/clk/sunxi-ng/ccu_nkm.h b/drivers/clk/sunxi-ng/ccu_nkm.h
index ff5bd00f429f..c82590481188 100644
--- a/drivers/clk/sunxi-ng/ccu_nkm.h
+++ b/drivers/clk/sunxi-ng/ccu_nkm.h
@@ -36,6 +36,7 @@ struct ccu_nkm {
unsigned int fixed_post_div;
unsigned int min_rate;
+ unsigned int max_rate;
struct ccu_common common;
};
--
2.18.0.321.gffc6fa0e3
