[PATCH] clk: sunxi-ng: h6: Keep both parents running while switching VP9 clock

[PATCH] clk: sunxi-ng: h6: Keep both parents running while switching VP9 clock

[Jernej Skrabec]

The VP9 clock mux only switches while both parents are running. Its
reset default parent is pll-ve, which is off at boot. When the Hantro
driver sets the clock rate to 300 MHz, the clock gets reparented to
pll-periph0-2x, but the mux doesn't actually switch until pll-ve is
enabled for the video engine. Until then, the VP9 decoder has no clock
and every frame times out.

Set CLK_OPS_PARENT_ENABLE, so both parents are enabled during the
switch.

Fixes: 524353ea480b ("clk: sunxi-ng: add support for the Allwinner H6 CCU")
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
---
 drivers/clk/sunxi-ng/ccu-sun50i-h6.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-h6.c b/drivers/clk/sunxi-ng/ccu-sun50i-h6.c
index 7fccda96d444..a10f0502c5c1 100644
--- a/drivers/clk/sunxi-ng/ccu-sun50i-h6.c
+++ b/drivers/clk/sunxi-ng/ccu-sun50i-h6.c
@@ -336,12 +336,17 @@ static SUNXI_CCU_MP_WITH_MUX_GATE(emce_clk, "emce", ce_parents, 0x6b0,
 static SUNXI_CCU_GATE(bus_emce_clk, "bus-emce", "psi-ahb1-ahb2",
 		      0x6bc, BIT(0), 0);
 
+/*
+ * The mux only switches while both parents run. pll-ve is off at boot, so
+ * moving the clock away from it would otherwise leave the VP9 decoder
+ * without a clock until pll-ve gets enabled for the video engine.
+ */
 static const char * const vp9_parents[] = { "pll-ve", "pll-periph0-2x" };
 static SUNXI_CCU_M_WITH_MUX_GATE(vp9_clk, "vp9", vp9_parents, 0x6c0,
 				       0, 3,	/* M */
 				       24, 1,	/* mux */
 				       BIT(31),	/* gate */
-				       0);
+				       CLK_OPS_PARENT_ENABLE);
 
 static SUNXI_CCU_GATE(bus_vp9_clk, "bus-vp9", "psi-ahb1-ahb2",
 		      0x6cc, BIT(0), 0);
-- 
2.43.0