[PATCH 07/13] arm64: dts: ti: k3-am69-aquila: fix USB clocking for compliance

[Siddharth Vadapalli]

On 05/05/26 16:38, Francesco Dolcini wrote:
> Hi Siddharth,
> 
> On Tue, May 05, 2026 at 04:36:08PM +0530, Siddharth Vadapalli wrote:
>> According to section "6.5.3 Normative Spread Spectrum Clocking (SSC)" of
>> the USB 3.2 Specification, SSC should be enabled by default. This protects
>> against EMI violations. Hence, enable internal SSC for USB SuperSpeed.
>>
>> Fixes: 39ac6623b1d8 ("arm64: dts: ti: Add Aquila AM69 Support")
>> Cc: <stable at vger.kernel.org>
>> Signed-off-by: Siddharth Vadapalli <s-vadapalli at ti.com>
>> ---
>>   arch/arm64/boot/dts/ti/k3-am69-aquila.dtsi | 6 ++++++
>>   1 file changed, 6 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/ti/k3-am69-aquila.dtsi b/arch/arm64/boot/dts/ti/k3-am69-aquila.dtsi
>> index 5119baf62a4c..7c98ee81ccb5 100644
>> --- a/arch/arm64/boot/dts/ti/k3-am69-aquila.dtsi
>> +++ b/arch/arm64/boot/dts/ti/k3-am69-aquila.dtsi
>> @@ -1423,6 +1423,7 @@ serdes0_usb0_ss_link: phy at 3 {
>>   		resets = <&serdes_wiz0 4>;
>>   		cdns,num-lanes = <1>;
>>   		cdns,phy-type = <PHY_TYPE_USB3>;
>> +		cdns,ssc-mode = <2>; /* 2 for internal SSC */
>>   	};
>>   };
>>   
>> @@ -1502,6 +1503,11 @@ &serdes_ln_ctrl {
>>   
>>   &serdes_wiz0 {
>>   	status = "okay";
>> +	ti,core-clk-sel = <1>;  /* Select internal reference clock */
>> +	ti,ssc-enable; /* Enable SSC */
>> +	ti,ssc-type = <1>; /* 1 for Downspread */
>> +	ti,ssc-frequency-hz = <33000>; /* 33 KHz */
>> +	ti,ssc-depth-per-mil = <5>; /* 0.5% depth */
> 
> These properties must go before status. Please see the coding guideline.
Thank you for pointing it out. I will fix this in all relevant patches of 
this series and post the v2 series in a day (to allow others to review as 
well).

As indicated in the cover letter, I was able to test this series on all TI 
Boards (EVMs / SKs). It will help if you could test this series on Toradex 
boards.

Regards,
Siddharth.