Re: [PATCH 3/7] firmware: arm_scmi: imx: Support getting cfg info of MISC protocol

[Sudeep Holla <sudeep.holla@arm.com>]

On Fri, Jul 04, 2025 at 06:07:41PM +0800, Peng Fan wrote:
> On Wed, Jul 02, 2025 at 04:21:58PM +0100, Sudeep Holla wrote:
> >On Fri, Jun 27, 2025 at 02:03:46PM +0800, Peng Fan wrote:
> >> MISC protocol supports getting the System Manager(SM) mode selection
> >> and configuration name. Add the API for user to retrieve the information
> >> from SM.
> >> 
> >> Signed-off-by: Peng Fan <peng.fan@nxp.com>
> >> ---
> >>  .../firmware/arm_scmi/vendors/imx/imx-sm-misc.c    | 30 ++++++++++++++++++++++
> >>  include/linux/scmi_imx_protocol.h                  |  5 ++++
> >>  2 files changed, 35 insertions(+)
> >> 
> >> diff --git a/drivers/firmware/arm_scmi/vendors/imx/imx-sm-misc.c b/drivers/firmware/arm_scmi/vendors/imx/imx-sm-misc.c
> >> index 1b24d070c6f4856b92f515fcdba5836fd6498ce6..8ce4bf92e6535af2f30d72a34717678613b35049 100644
> >> --- a/drivers/firmware/arm_scmi/vendors/imx/imx-sm-misc.c
> >> +++ b/drivers/firmware/arm_scmi/vendors/imx/imx-sm-misc.c
> >> @@ -26,6 +26,7 @@ enum scmi_imx_misc_protocol_cmd {
> >>  	SCMI_IMX_MISC_CTRL_SET	= 0x3,
> >>  	SCMI_IMX_MISC_CTRL_GET	= 0x4,
> >>  	SCMI_IMX_MISC_DISCOVER_BUILDINFO = 0x6,
> >> +	SCMI_IMX_MISC_CFG_INFO = 0xC,
> >>  	SCMI_IMX_MISC_CTRL_NOTIFY = 0x8,
> >>  };
> >>  
> >> @@ -73,6 +74,11 @@ struct scmi_imx_misc_buildinfo_out {
> >>  	u8 buildtime[MISC_MAX_BUILDTIME];
> >>  };
> >>  
> >> +struct scmi_imx_misc_cfg_info_out {
> >> +	__le32 msel;
> >
> >Now, I realise, this mode select is not properly defined in the document.
> >Just 32-bit word. What are those values ? Any fixed list of values with
> >well defined modes or configurations ? If so, please add to the document.
> 
> The current used value are 0,1,2. It is used to decide the logic machine
> boot order, such as 0 means booting LM0, LM1, LM2, LM3...
> Regarding 0,1,2 using which LM order, it could be defined by user in
> i.MX9 System Manger cfg file. That means 1 could mean LM0, LM2, LM3, LM1
> or LM0, LM3, LM1, LM2.
> 

This sounds like this is not well defined and could change on a different
platform ? If so, how will you manage this extension across i.MX platforms ?

Or the above order is actually fixed and will remain same across the
platforms ?

-- 
Regards,
Sudeep