RE: [PATCH V2 12/12] imx: imx8m: move CONFIG_SPL_SYS_[I,D]CACHE_OFF to defconfig

Subject: Re: [PATCH V2 12/12] imx: imx8m: move CONFIG_SPL_SYS_[I,D]CACHE_OFF to defconfig

Hi Peng

On Sun, Jan 3, 2021 at 6:43 AM Peng Fan (OSS) peng.fan@oss.nxp.com wrote:

...

diff --git a/configs/imx8mn_ddr4_evk_defconfig b/configs/imx8mn_ddr4_evk_defconfig index b4b511ed43..d6000d9e87 100644 --- a/configs/imx8mn_ddr4_evk_defconfig +++ b/configs/imx8mn_ddr4_evk_defconfig @@ -1,4 +1,6 @@ CONFIG_ARM=y +CONFIG_SPL_SYS_ICACHE_OFF=y +CONFIG_SPL_SYS_DCACHE_OFF=y

I understand that this patch is just moving these symbols from include file to defconfig, but a more fundamental question: why do we need to disable caches in the first place?

No need to disable icache. Dcache needs to be off, since we not have MMU setup.

I could use a follow up patch to enable icache, agree?

Thanks, Peng.

My understanding is that it is safe to run with caches enabled on these imx8 platforms.

Please clarify.

Thanks,

Fabio Estevam