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S32G Linux with ATF adjust clock for spread spectrum

Hi Linux BSP team,

Customer inquired the guidance on how to adjust the clock spread spectrum settings in the Linux BSP with ATF.

I checked S32G latest BSP, the following clock spread spectrum related PLL Frequency Modulation(PLLFM)register configuration is not found.

My question is that do we have the plan to add this support in Linux BSP?

BRs,

Tianxiang

Linux BSPRe: S32G Linux with ATF adjust clock for spread spectrum

Rather than spread spectrum that can in theory only works at 1516MHz (DS value just below 1600MHz) as it is not down-spread, meaning you overclock you DDR otherwise, Valeo has decided to simply move the DDR freq to 1590MHz (far closer to 1600MHz) as it is easier to implement compared to SS. But as 1590MHz, is not in the DS and calibration tool, it is at their own risk. Here is the article:

[S32G] change the DDR frequency to 1590MHz and measure the results with a 20€ SDR dongle

Re: S32G Linux with ATF adjust clock for spread spectrum

Hi Ghennadi,

Got it, thanks for the quick confirmation.

BRs,

Tianxiang

Re: S32G Linux with ATF adjust clock for spread spectrum

Hi @Tianxiang_Huang ,

As of today, the clock spread spectrum for DDR PLL Frequency Modulation is not supported, and it is not planned to be added anytime soon. A detailed change request is needed in case this is relevant for one or more clients. Please take into account that any DDR-related change has to be synchronized with DDR tool given that TF-A integrates the code generated by this tool. 

Regards,

Ghennadi