Re: [PATCH 2/2] arm64: dts: imx8qm-tqma8qm: Re-enable A72 cluster after ERR050104 workaround

[Alexander Stein]

Hi Peng,

thanks for the patch.

Am Donnerstag, 22. Oktober 2026, 03:50:02 Mitteleuropäische Sommerzeit schrieb Peng Fan (OSS):
> From: Peng Fan <peng.fan@xxxxxxx>
> 
> The ERR050104 cache coherency workaround for i.MX8QM/8QP has been
> merged upstream (d44e08dab27d). The workaround addresses the incorrect
> wiring of upper address bits in the A53 subsystem that corrupts TLBI and
> IC maintenance operations between A53 and A72 clusters.
> 
> Previously the A72 CPUs (cpu@100, cpu@101) and cpu-map were removed
> from the TQMa8QM DTSI with an explicit comment "Due to missing
> workaround for ERR050104". With the software workaround is in place,
> remove the workaround-comment block and restore the full SMP topology.
> 
> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> ---
>  arch/arm64/boot/dts/freescale/imx8qm-tqma8qm.dtsi | 7 -------
>  1 file changed, 7 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/freescale/imx8qm-tqma8qm.dtsi b/arch/arm64/boot/dts/freescale/imx8qm-tqma8qm.dtsi
> index f0e398eb2aad7..8cd6e75eb87a9 100644
> --- a/arch/arm64/boot/dts/freescale/imx8qm-tqma8qm.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8qm-tqma8qm.dtsi
> @@ -15,13 +15,6 @@ / {
>  	model = "TQ-Systems i.MX8QM TQMa8QM";
>  	compatible = "tq,imx8qm-tqma8qm", "fsl,imx8qm";
>  
> -	/* Due to missing workaround for ERR050104 */
> -	cpus {
> -		/delete-node/ cpu-map;
> -		/delete-node/ cpu@100;
> -		/delete-node/ cpu@101;
> -	};
> -

While the patch itself is correct, it is not sufficient. Instead please
revert commit 5d20f1ccb3393 ("arm64: dts: imx8qm-tqma8qm-mba8x: Disable
Cortex-A72 cluster"). This will restore the thermal zone for cpu1-cluster.
This commit was created with the intention to be reverted, once the
errata has been dealt with.
With the revert:
Reviewed-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>

Thanks and best regards,
Alexander

>  	memory@80000000 {
>  		device_type = "memory";
>  		/*
> 
> 


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