Hi Balaji, On 16/06/2026 11:22, 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.
Since we know we're in snagboot mode, as I mentioned before we don't need this additional option, just check for CONFIG_QCOM_SNAGBOOT_MODE instead rather than introduce another footgun. > > Signed-off-by: Balaji Selvanathan <[email protected]> > --- > Changes in v3: > - Used "if (IS_ENABLED(CONFIG_QCOM_COMMAND_DB_OPTIONAL))" instead > of #ifdef > > Changes in v2: > - No changes > --- > drivers/soc/qcom/Kconfig | 18 ++++++++++++++++++ > drivers/soc/qcom/cmd-db.c | 14 ++++++++++++-- > 2 files changed, 30 insertions(+), 2 deletions(-) > > diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig > index 8243805e46a..7f4cf1b9a98 100644 > --- a/drivers/soc/qcom/Kconfig > +++ b/drivers/soc/qcom/Kconfig > @@ -18,6 +18,24 @@ 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 the > + previous bootloader (e.g., snagboot mode where XBL loads U-Boot > + directly without initializing CMD DB). > + > + 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..9b5091f5b5a 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)) { > - log_err("%s: Invalid Command DB Magic\n", __func__); > - return -EINVAL; > + if (IS_ENABLED(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__); You can drop these warnings if snagboot mode is enabled since that's the expected case. I think it would be more appropriate to log a warning if snagboot is enabled and we DO have a valid cmd-db, since that isn't an expected usecase right? Kind regards, > + cmd_db_header = NULL; > + return 0; > + } else { > + log_err("%s: Invalid Command DB Magic\n", __func__); > + return -EINVAL; > + } > } > > return 0; > -- // Casey (she/her)
