Re: [PATCH 3/4] firmware: qcom: scm: Add minidump SRAM support

[Mukesh Ojha]

On Fri, May 08, 2026 at 12:40:35PM +0200, Konrad Dybcio wrote:
> On 5/7/26 3:50 PM, Dmitry Baryshkov wrote:
> > On Thu, May 07, 2026 at 01:37:19PM +0530, Mukesh Ojha wrote:
> >> On most Qualcomm SoCs where minidump is supported, a word in always-on
> >> SRAM is shared between the kernel and boot firmware. Before DDR is
> >> initialised on the warm reset following a crash, firmware reads this
> >> word to decide if minidump is enabled and collect a minidump and where
> >> to deliver it (USB upload to a host, or save to local storage).
> >>
> >> The SRAM region is described by a 'sram'/'sram-names' phandle pair on
> >> the SCM DT node. If the property is absent the feature is silently
> >> disabled, keeping existing SoCs unaffected.
> >>
> >> Expose a 'minidump_dest' module parameter (default: usb) so the user can
> >> select the destination. Only the string names "usb" or "storage" are
> >> accepted; an invalid value is rejected with -EINVAL. Changing the
> >> destination while minidump mode is already active updates SRAM immediately.
> >>
> >> Suggested-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
> >> Signed-off-by: Mukesh Ojha <mukesh.ojha@xxxxxxxxxxxxxxxx>
> >> ---
> 
> 
> >> +	if (of_property_match_string(np, "sram-names", "minidump") < 0)
> >> +		return 0;
> > 
> > Do you actually need sram-names? Just to verify that it has one string?
> 
> I requested that, because SCM is a very generic node and index-based
> lookups would age like fine milk

I am going to drop this as per Rob's comment. Let me know if you think otherwise.

> 
> Konrad

-- 
-Mukesh Ojha