[PATCH] ARM: imx: Get rid of only i.MX8M SMCCC arch call

[Peng Fan (OSS)]

On 2022/3/31 10:56, Marek Vasut wrote:
> This is the only place where i.MX8M code does SMCCC call, remove it.
> The output has little value as it prints some part of commit ID, and
> worse, if there is no SMC handler installed, the code outright hangs
> or crashes the system.
> 
> By removing this one instance of SMCCC call, U-Boot no longer depends
> on SMC handlers and can boot without hanging in any case. If there is
> a need to dump this commit ID, use CMD_SMC instead and do 'smc' call
> from U-Boot shell or scripts instead of hard-coding SMCCC dependency
> into architecture code. This particular code can be replaced by:
>   => smc 0xc2000003 0 0 0 0 0 0
> 
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Fabio Estevam <festevam at gmail.com>
> Cc: Peng Fan <peng.fan at nxp.com>
> Cc: Stefano Babic <sbabic at denx.de>
This should be ok, since ATF could print out log itself during boot.

Reviewed-by: Peng Fan <peng.fan at nxp.com>

> ---
> NOTE: This could also be hidden behind ARM_PSCI_FW , but I would rather
>        just remove this hard dependency, it makes U-Boot porting easier.
> ---
>   arch/arm/mach-imx/imx8m/soc.c | 20 --------------------
>   1 file changed, 20 deletions(-)
> 
> diff --git a/arch/arm/mach-imx/imx8m/soc.c b/arch/arm/mach-imx/imx8m/soc.c
> index 1a5a391443d..45c5476bbc7 100644
> --- a/arch/arm/mach-imx/imx8m/soc.c
> +++ b/arch/arm/mach-imx/imx8m/soc.c
> @@ -27,7 +27,6 @@
>   #include <fdt_support.h>
>   #include <fsl_wdog.h>
>   #include <imx_sip.h>
> -#include <linux/arm-smccc.h>
>   #include <linux/bitops.h>
>   
>   DECLARE_GLOBAL_DATA_PTR;
> @@ -1191,27 +1190,8 @@ void reset_cpu(void)
>   #endif
>   
>   #if defined(CONFIG_ARCH_MISC_INIT)
> -static void acquire_buildinfo(void)
> -{
> -	u64 atf_commit = 0;
> -	struct arm_smccc_res res;
> -
> -	/* Get ARM Trusted Firmware commit id */
> -	arm_smccc_smc(IMX_SIP_BUILDINFO, IMX_SIP_BUILDINFO_GET_COMMITHASH,
> -		      0, 0, 0, 0, 0, 0, &res);
> -	atf_commit = res.a0;
> -	if (atf_commit == 0xffffffff) {
> -		debug("ATF does not support build info\n");
> -		atf_commit = 0x30; /* Display 0, 0 ascii is 0x30 */
> -	}
> -
> -	printf("\n BuildInfo:\n  - ATF %s\n\n", (char *)&atf_commit);
> -}
> -
>   int arch_misc_init(void)
>   {
> -	acquire_buildinfo();
> -
>   	return 0;
>   }
>   #endif
>