[PATCH v2 4/6] soc: qcom: cmd-db: Allow boot without CMD DB data

[Varadarajan Narayanan]

On Mon, Jun 08, 2026 at 02:36:31PM +0530, Balaji Selvanathan wrote:
> In snagboot mode, XBL loads U-Boot directly without populating CMD DB.
> The cmd-db driver fails to bind when CMD DB magic is invalid, blocking
> boot even when CMD DB is not strictly required.
>
> Add QCOM_COMMAND_DB_OPTIONAL config to allow the driver to bind
> successfully when CMD DB data is absent. When enabled, a warning is
> logged and cmd_db_header is set to NULL, so consumer drivers receive
> errors on resource queries rather than preventing boot entirely.
>
> Signed-off-by: Balaji Selvanathan <balaji.selvanathan at oss.qualcomm.com>
> ---
> Changes in v2:
> - No changes
> ---
>  drivers/soc/qcom/Kconfig  | 16 ++++++++++++++++
>  drivers/soc/qcom/cmd-db.c | 10 ++++++++++
>  2 files changed, 26 insertions(+)
>
> diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
> index 8243805e46a..239d87e044f 100644
> --- a/drivers/soc/qcom/Kconfig
> +++ b/drivers/soc/qcom/Kconfig
> @@ -18,6 +18,22 @@ config QCOM_COMMAND_DB
>  	  resource on a RPM-hardened platform must use this database to get
>  	  SoC specific identifier and information for the shared resources.
>
> +config QCOM_COMMAND_DB_OPTIONAL
> +	bool "Allow operation without Command DB data"
> +	depends on QCOM_COMMAND_DB
> +	help
> +	  Allow the Command DB driver to bind successfully even when CMD DB
> +	  data is not populated or has an invalid magic number.
> +
> +	  This is useful for platforms where CMD DB is not populated by

incomplete sentence?

-Varada

> +
> +	  When enabled, missing CMD DB will generate warnings but allow boot
> +	  to continue. Consumer drivers must handle cmd_db API failures
> +	  gracefully by checking return values.
> +
> +	  If unsure, say N. Most production Qualcomm platforms require
> +	  valid CMD DB data.
> +
>  config QCOM_RPMH
>  	bool "Qualcomm RPMh support"
>  	depends on QCOM_COMMAND_DB
> diff --git a/drivers/soc/qcom/cmd-db.c b/drivers/soc/qcom/cmd-db.c
> index d0a6047b8a6..b4682d811f7 100644
> --- a/drivers/soc/qcom/cmd-db.c
> +++ b/drivers/soc/qcom/cmd-db.c
> @@ -252,8 +252,18 @@ static int cmd_db_bind(struct udevice *dev)
>
>  	cmd_db_header = base;
>  	if (!cmd_db_magic_matches(cmd_db_header)) {
> +#ifdef CONFIG_QCOM_COMMAND_DB_OPTIONAL
> +		log_warning("%s: CMD DB magic not found (0x%02x%02x%02x%02x)\n",
> +			    __func__, cmd_db_header->magic[0], cmd_db_header->magic[1],
> +			    cmd_db_header->magic[2], cmd_db_header->magic[3]);
> +		log_warning("%s: CMD DB data unavailable, resource queries will fail\n",
> +			    __func__);
> +		cmd_db_header = NULL;
> +		return 0;
> +#else
>  		log_err("%s: Invalid Command DB Magic\n", __func__);
>  		return -EINVAL;
> +#endif
>  	}
>
>  	return 0;
>
> --
> 2.34.1
>