Re: [PATCH v4 2/7] reset: Add explicit cold reset support

[Quentin Schulz <quentin.schulz@cherry.de>]

Hi Denis,

On 6/3/26 9:07 AM, dmukhin@ford.com wrote:
> Some prototype boards default to a non-cold reset type, e.g. warm reset.
> 
> Add 'reset -c' so users can explicitly request a cold reset when needed.
> 
> Signed-off-by: Denis Mukhin <dmukhin@ford.com>
> ---
> Changes since v3:
> - preserved existing behavior for 'reset -edl' handling
> - corrected commit message formatting
> ---
>   cmd/boot.c                         |  3 ++-
>   drivers/sysreset/sysreset-uclass.c | 13 +++++++++++--
>   2 files changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/cmd/boot.c b/cmd/boot.c
> index 29cdf4a9a81a..5cac6cf3fed0 100644
> --- a/cmd/boot.c
> +++ b/cmd/boot.c
> @@ -59,13 +59,14 @@ U_BOOT_CMD(
>   U_BOOT_CMD(
>   	reset, 2, 0,	do_reset,
>   	"Perform RESET of the CPU",
> -	"- cold boot without level specifier\n"
> +	"- reset using the configured default type\n"

NACK. It performs a cold boot when the level (-w) is not specified so we 
need to keep this as is.

>   #if IS_ENABLED(CONFIG_SYSRESET_CMD_RESET_ARGS)
>   // All options handled by sysreset drivers via their sysreset_ops.request_arg callback
>   #ifdef CONFIG_SYSRESET_QCOM_PSCI
>   	"reset -edl - Boot to Emergency DownLoad mode\n"
>   #endif
>   #endif
> +	"reset -c - cold reset if implemented\n"

But... why? `reset` already does that why do we need yet another option 
for something we already do when no argument is passed?

>   	"reset -w - warm reset if implemented"
>   );
>   
> diff --git a/drivers/sysreset/sysreset-uclass.c b/drivers/sysreset/sysreset-uclass.c
> index 5c6dd7cc1c55..1ba698b37285 100644
> --- a/drivers/sysreset/sysreset-uclass.c
> +++ b/drivers/sysreset/sysreset-uclass.c
> @@ -168,8 +168,17 @@ int do_reset(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
>   	if (argc > 2)
>   		return CMD_RET_USAGE;
>   
> -	if (argc == 2 && argv[1][0] == '-' && argv[1][1] == 'w') {
> -		reset_type = SYSRESET_WARM;
> +	if (argc == 2 && argv[1][0] == '-' && strlen(argv[1]) == 2) {
> +		switch (argv[1][1]) {
> +		case 'c':
> +			reset_type = SYSRESET_COLD;
> +			break;
> +		case 'w':
> +			reset_type = SYSRESET_WARM;
> +			break;
> +		default:
> +			return CMD_RET_USAGE;

NACK. We support passing arguments to sysreset drivers whenever -w is 
not passed, so this will break them. See the sysreset_walk_arg below.

Cheers,
Quentin