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[PATCH 2/2] arm64: dts: amlogic: s4: fix mmc clock assignment

Jerome Brunet posted 2 patches 3 weeks, 6 days ago
There is a newer version of this series
[PATCH 2/2] arm64: dts: amlogic: s4: fix mmc clock assignment
Posted by Jerome Brunet 3 weeks, 6 days ago 
MMC A and C are mis-represented as having their "clkin0" input connected to
xtal while it is actually connected to the MMC clock, mostly in an attempt
to provide 24MHz to the device on this input.

Fix this and assign the clock to 24MHz to actually provide the required
rate.

Fixes: 3ab9d54b5d84 ("arm64: dts: amlogic: enable some device nodes for S4")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 arch/arm64/boot/dts/amlogic/meson-s4.dtsi | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/amlogic/meson-s4.dtsi b/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
index 62538fd9db6b1ffb33a88e12628aadefbaa453ec..6324d1eb5994009df5b09923cce373a87229f4b8 100644
--- a/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
@@ -819,13 +819,17 @@ sdio: mmc@fe088000 {
 			reg = <0x0 0xfe088000 0x0 0x800>;
 			interrupts = <GIC_SPI 176 IRQ_TYPE_LEVEL_HIGH>;
 			clocks = <&clkc_periphs CLKID_SDEMMC_A>,
-				 <&xtal>,
+				 <&clkc_periphs CLKID_SD_EMMC_A>,
 				 <&clkc_pll CLKID_FCLK_DIV2>;
 			clock-names = "core", "clkin0", "clkin1";
 			resets = <&reset RESET_SD_EMMC_A>;
 			cap-sdio-irq;
 			keep-power-in-suspend;
 			status = "disabled";
+
+			assigned-clocks = <&clkc_periphs CLKID_SD_EMMC_A>;
+			assigned-clock-parents = <0>;
+			assigned-clock-rates = <24000000>;
 		};
 
 		sd: mmc@fe08a000 {
@@ -849,13 +853,17 @@ emmc: mmc@fe08c000 {
 			reg = <0x0 0xfe08c000 0x0 0x800>;
 			interrupts = <GIC_SPI 178 IRQ_TYPE_EDGE_RISING>;
 			clocks = <&clkc_periphs CLKID_NAND>,
-				 <&xtal>,
+				 <&clkc_periphs CLKID_SD_EMMC_C>,
 				 <&clkc_pll CLKID_FCLK_DIV2>;
 			clock-names = "core", "clkin0", "clkin1";
 			resets = <&reset RESET_NAND_EMMC>;
 			no-sdio;
 			no-sd;
 			status = "disabled";
+
+			assigned-clocks = <&clkc_periphs CLKID_SD_EMMC_C>;
+			assigned-clock-parents = <0>;
+			assigned-clock-rates = <24000000>;
 		};
 	};
 };

-- 
2.47.3
Re: [PATCH 2/2] arm64: dts: amlogic: s4: fix mmc clock assignment
Posted by Chuan Liu 3 weeks, 5 days ago 
hi Jerome,

On 1/13/2026 6:39 PM, Jerome Brunet wrote:
> [ EXTERNAL EMAIL ]
> 
> MMC A and C are mis-represented as having their "clkin0" input connected to
> xtal while it is actually connected to the MMC clock, mostly in an attempt
> to provide 24MHz to the device on this input.

Right.

> 
> Fix this and assign the clock to 24MHz to actually provide the required
> rate.
> 
> Fixes: 3ab9d54b5d84 ("arm64: dts: amlogic: enable some device nodes for S4")
> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
> ---
>   arch/arm64/boot/dts/amlogic/meson-s4.dtsi | 12 ++++++++++--
>   1 file changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/amlogic/meson-s4.dtsi b/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
> index 62538fd9db6b1ffb33a88e12628aadefbaa453ec..6324d1eb5994009df5b09923cce373a87229f4b8 100644
> --- a/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
> +++ b/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
> @@ -819,13 +819,17 @@ sdio: mmc@fe088000 {
>                          reg = <0x0 0xfe088000 0x0 0x800>;
>                          interrupts = <GIC_SPI 176 IRQ_TYPE_LEVEL_HIGH>;
>                          clocks = <&clkc_periphs CLKID_SDEMMC_A>,
> -                                <&xtal>,
> +                                <&clkc_periphs CLKID_SD_EMMC_A>,
>                                   <&clkc_pll CLKID_FCLK_DIV2>;
>                          clock-names = "core", "clkin0", "clkin1";
>                          resets = <&reset RESET_SD_EMMC_A>;
>                          cap-sdio-irq;
>                          keep-power-in-suspend;
>                          status = "disabled";
> +
> +                       assigned-clocks = <&clkc_periphs CLKID_SD_EMMC_A>;
> +                       assigned-clock-parents = <0>;

Is it possible to remove assigned-clock-parent?

> +                       assigned-clock-rates = <24000000>;
>                  };
> 
>                  sd: mmc@fe08a000 {
> @@ -849,13 +853,17 @@ emmc: mmc@fe08c000 {
>                          reg = <0x0 0xfe08c000 0x0 0x800>;
>                          interrupts = <GIC_SPI 178 IRQ_TYPE_EDGE_RISING>;
>                          clocks = <&clkc_periphs CLKID_NAND>,
> -                                <&xtal>,
> +                                <&clkc_periphs CLKID_SD_EMMC_C>,
>                                   <&clkc_pll CLKID_FCLK_DIV2>;
>                          clock-names = "core", "clkin0", "clkin1";
>                          resets = <&reset RESET_NAND_EMMC>;
>                          no-sdio;
>                          no-sd;
>                          status = "disabled";
> +
> +                       assigned-clocks = <&clkc_periphs CLKID_SD_EMMC_C>;
> +                       assigned-clock-parents = <0>;
> +                       assigned-clock-rates = <24000000>;
>                  };
>          };
>   };
> 
> --
> 2.47.3
> 
> 
> _______________________________________________
> linux-amlogic mailing list
> linux-amlogic@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-amlogic
Re: [PATCH 2/2] arm64: dts: amlogic: s4: fix mmc clock assignment
Posted by Neil Armstrong 3 weeks, 5 days ago 
On 1/14/26 03:48, Chuan Liu wrote:
> hi Jerome,
> 
> On 1/13/2026 6:39 PM, Jerome Brunet wrote:
>> [ EXTERNAL EMAIL ]
>>
>> MMC A and C are mis-represented as having their "clkin0" input connected to
>> xtal while it is actually connected to the MMC clock, mostly in an attempt
>> to provide 24MHz to the device on this input.
> 
> Right.
> 
>>
>> Fix this and assign the clock to 24MHz to actually provide the required
>> rate.
>>
>> Fixes: 3ab9d54b5d84 ("arm64: dts: amlogic: enable some device nodes for S4")
>> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
>> ---
>>   arch/arm64/boot/dts/amlogic/meson-s4.dtsi | 12 ++++++++++--
>>   1 file changed, 10 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/arm64/boot/dts/amlogic/meson-s4.dtsi b/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
>> index 62538fd9db6b1ffb33a88e12628aadefbaa453ec..6324d1eb5994009df5b09923cce373a87229f4b8 100644
>> --- a/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
>> +++ b/arch/arm64/boot/dts/amlogic/meson-s4.dtsi
>> @@ -819,13 +819,17 @@ sdio: mmc@fe088000 {
>>                          reg = <0x0 0xfe088000 0x0 0x800>;
>>                          interrupts = <GIC_SPI 176 IRQ_TYPE_LEVEL_HIGH>;
>>                          clocks = <&clkc_periphs CLKID_SDEMMC_A>,
>> -                                <&xtal>,
>> +                                <&clkc_periphs CLKID_SD_EMMC_A>,
>>                                   <&clkc_pll CLKID_FCLK_DIV2>;
>>                          clock-names = "core", "clkin0", "clkin1";
>>                          resets = <&reset RESET_SD_EMMC_A>;
>>                          cap-sdio-irq;
>>                          keep-power-in-suspend;
>>                          status = "disabled";
>> +
>> +                       assigned-clocks = <&clkc_periphs CLKID_SD_EMMC_A>;
>> +                       assigned-clock-parents = <0>;
> 
> Is it possible to remove assigned-clock-parent?

Yes it's not necessary to keep it.

Neil

> 
>> +                       assigned-clock-rates = <24000000>;
>>                  };
>>
>>                  sd: mmc@fe08a000 {
>> @@ -849,13 +853,17 @@ emmc: mmc@fe08c000 {
>>                          reg = <0x0 0xfe08c000 0x0 0x800>;
>>                          interrupts = <GIC_SPI 178 IRQ_TYPE_EDGE_RISING>;
>>                          clocks = <&clkc_periphs CLKID_NAND>,
>> -                                <&xtal>,
>> +                                <&clkc_periphs CLKID_SD_EMMC_C>,
>>                                   <&clkc_pll CLKID_FCLK_DIV2>;
>>                          clock-names = "core", "clkin0", "clkin1";
>>                          resets = <&reset RESET_NAND_EMMC>;
>>                          no-sdio;
>>                          no-sd;
>>                          status = "disabled";
>> +
>> +                       assigned-clocks = <&clkc_periphs CLKID_SD_EMMC_C>;
>> +                       assigned-clock-parents = <0>;
>> +                       assigned-clock-rates = <24000000>;
>>                  };
>>          };
>>   };
>>
>> -- 
>> 2.47.3
>>
>>
>> _______________________________________________
>> linux-amlogic mailing list
>> linux-amlogic@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-amlogic
>

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