From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Enable CLK_SET_RATE_PARENT for mux clocks so that rate changes can properly
propagate to their parent clocks. Several clocks in the R9A09G077 CPG tree
depend on upstream PLL or divider outputs being recalculated when a child
requests a new frequency. Without this flag, rate adjustments stop at the
mux layer, leaving parent rates unchanged and preventing the clock tree
from converging on the intended values.

Set the flag in DEF_MUX to ensure that parent clocks participate in rate
negotiation, which is required for correct operation of the display and
peripheral related clocks being added for RZ/T2H support.

Fixes: 065fe720eec6e ("clk: renesas: Add support for R9A09G077 SoC")
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
 drivers/clk/renesas/r9a09g077-cpg.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/renesas/r9a09g077-cpg.c b/drivers/clk/renesas/r9a09g077-cpg.c
index 7367a713991d..dfd77a1ecc92 100644
--- a/drivers/clk/renesas/r9a09g077-cpg.c
+++ b/drivers/clk/renesas/r9a09g077-cpg.c
@@ -78,7 +78,7 @@ enum rzt2h_clk_types {
 #define DEF_MUX(_name, _id, _conf, _parent_names, _num_parents, _mux_flags) \
 	DEF_TYPE(_name, _id, CLK_TYPE_RZT2H_MUX, .conf = _conf, \
 		 .parent_names = _parent_names, .num_parents = _num_parents, \
-		 .flag = 0, .mux_flags = _mux_flags)
+		 .flag = CLK_SET_RATE_PARENT, .mux_flags = _mux_flags)
 #define DEF_DIV_FSELXSPI(_name, _id, _parent, _conf, _dtable) \
 	DEF_TYPE(_name, _id, CLK_TYPE_RZT2H_FSELXSPI, .conf = _conf, \
 		 .parent = _parent, .dtable = _dtable, .flag = 0)
-- 
2.52.0

On Fri, 21 Nov 2025 at 10:09, Prabhakar <prabhakar.csengg@gmail.com> wrote:
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
>
> Enable CLK_SET_RATE_PARENT for mux clocks so that rate changes can properly
> propagate to their parent clocks. Several clocks in the R9A09G077 CPG tree
> depend on upstream PLL or divider outputs being recalculated when a child
> requests a new frequency. Without this flag, rate adjustments stop at the
> mux layer, leaving parent rates unchanged and preventing the clock tree
> from converging on the intended values.
>
> Set the flag in DEF_MUX to ensure that parent clocks participate in rate
> negotiation, which is required for correct operation of the display and
> peripheral related clocks being added for RZ/T2H support.
>
> Fixes: 065fe720eec6e ("clk: renesas: Add support for R9A09G077 SoC")
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
i.e. will queue in renesas-clk for v6.20.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds