diff mbox series

[2/4] clk: renesas: r8a779f0: Fix SCIF parent clocks

Message ID 20221103143440.46449-3-wsa+renesas@sang-engineering.com (mailing list archive)
State Accepted
Delegated to: Geert Uytterhoeven
Headers show
Series r8a779f0: update SCIF parent clocks | expand

Commit Message

Wolfram Sang Nov. 3, 2022, 2:34 p.m. UTC
As serial communication requires a clean clock signal, the Serial
Communication Interfaces with FIFO (SCIF) is clocked by a clock that is
not affected by Spread Spectrum or Fractional Multiplication.

Hence change the parent clocks for the SCIF modules from the S0D12_PER
clock to the SASYNCPERD4 clock (which has the same clock rate), cfr.
R-Car S4-8 Hardware User's Manual rev. 0.81.

Fixes: 24aaff6a6ce4 ("clk: renesas: cpg-mssr: Add support for R-Car S4-8")
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 drivers/clk/renesas/r8a779f0-cpg-mssr.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Comments

Geert Uytterhoeven Nov. 7, 2022, 4:11 p.m. UTC | #1
On Thu, Nov 3, 2022 at 3:34 PM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> As serial communication requires a clean clock signal, the Serial
> Communication Interfaces with FIFO (SCIF) is clocked by a clock that is
> not affected by Spread Spectrum or Fractional Multiplication.
>
> Hence change the parent clocks for the SCIF modules from the S0D12_PER
> clock to the SASYNCPERD4 clock (which has the same clock rate), cfr.
> R-Car S4-8 Hardware User's Manual rev. 0.81.
>
> Fixes: 24aaff6a6ce4 ("clk: renesas: cpg-mssr: Add support for R-Car S4-8")
> Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
i.e. will queue in renesas-clk-for-v6.2.

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
diff mbox series

Patch

diff --git a/drivers/clk/renesas/r8a779f0-cpg-mssr.c b/drivers/clk/renesas/r8a779f0-cpg-mssr.c
index fd1462425316..800fdc104edd 100644
--- a/drivers/clk/renesas/r8a779f0-cpg-mssr.c
+++ b/drivers/clk/renesas/r8a779f0-cpg-mssr.c
@@ -144,10 +144,10 @@  static const struct mssr_mod_clk r8a779f0_mod_clks[] __initconst = {
 	DEF_MOD("msiof3",	621,	R8A779F0_CLK_MSO),
 	DEF_MOD("pcie0",	624,	R8A779F0_CLK_S0D2),
 	DEF_MOD("pcie1",	625,	R8A779F0_CLK_S0D2),
-	DEF_MOD("scif0",	702,	R8A779F0_CLK_S0D12_PER),
-	DEF_MOD("scif1",	703,	R8A779F0_CLK_S0D12_PER),
-	DEF_MOD("scif3",	704,	R8A779F0_CLK_S0D12_PER),
-	DEF_MOD("scif4",	705,	R8A779F0_CLK_S0D12_PER),
+	DEF_MOD("scif0",	702,	R8A779F0_CLK_SASYNCPERD4),
+	DEF_MOD("scif1",	703,	R8A779F0_CLK_SASYNCPERD4),
+	DEF_MOD("scif3",	704,	R8A779F0_CLK_SASYNCPERD4),
+	DEF_MOD("scif4",	705,	R8A779F0_CLK_SASYNCPERD4),
 	DEF_MOD("sdhi0",        706,    R8A779F0_CLK_SD0),
 	DEF_MOD("sys-dmac0",	709,	R8A779F0_CLK_S0D3_PER),
 	DEF_MOD("sys-dmac1",	710,	R8A779F0_CLK_S0D3_PER),