Re: [PATCH v3] arm64: errata: Add NXP iMX8QM workaround for A53 cache coherency issue

From: Francesco Dolcini

Date: Mon Aug 10 2026 - 11:12:52 EST


Hello Peng,
thanks for the patch, very much appreciated.

On Mon, Aug 03, 2026 at 04:54:44PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
>
> According to NXP errata document IMX8_1N94W[1], the i.MX8QuadMax SoC
> suffers from a cache coherency issue (ERR050104). The upper bits, above
> bit 35, of the ARADDR and ACADDR buses within the Arm A53 subsystem
> have been incorrectly connected. This causes some TLBI and IC
> maintenance operations exchanged between the A53 and A72 core clusters
> to be corrupted.

...

> diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
> index 5db8f0619e4b..4ba68c1f29b2 100644
> --- a/arch/arm64/kernel/cpu_errata.c
> +++ b/arch/arm64/kernel/cpu_errata.c
> @@ -200,6 +202,28 @@ cpu_enable_cache_maint_trap(const struct arm64_cpu_capabilities *__unused)
> sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCI, 0);
> }
>
> +#ifdef CONFIG_NXP_IMX8QM_ERRATUM_ERR050104
> +static bool
> +is_imx8qm_soc(const struct arm64_cpu_capabilities *entry, int scope)
> +{
> + WARN_ON(preemptible());
> +
> + return of_machine_is_compatible("fsl,imx8qm");

fsl,imx8qp is also affected, please adjust


Francesco