Dear Krzysztof, Il Sat, Apr 13, 2024 at 12:58:35PM +0200, Krzysztof Kozlowski ha scritto: > On 12/04/2024 09:21, Fabio Aiuto wrote: > > Dear Krzysztof, > > > > Il Thu, Apr 11, 2024 at 09:52:12PM +0200, Krzysztof Kozlowski ha scritto: > >> On 11/04/2024 18:58, Fabio Aiuto wrote: > >>> Add property to trigger warm reset on PMIC_RST_B assertion > >>> > >> > >> That's rather vague and does not tell me much why this is supposed to be > >> board level configuration. It sounds more like a debugging feature: > >> during development you want to retain memory contents for pstore etc. > >> Then I could imagine this should be turned runtime, e.g. via > >> sysfs/debugfs, because for example you want to start inspecting a > >> customer's device. > > > > thanks, I spent too few time writing this commit log and I apologize > > for that. I was thinking about something like: > > > > The default configuration of the PMIC behavior makes the PMIC > > power cycle most regulators on PMIC_RST_B assertion. This power > > cycling causes the memory contents of OCRAM to be lost. > > Some systems needs some memory that survives reset and > > reboot, therefore add a property to tell PMIC_RST_B is > > wired. > > > > The actual configuration is made at probe time, anyway we need > > to override the default behavior of the pmic to get a warm reset > > everytime the PMIC_RST_B pin is asserted and this property tells > > us that "something is wired to that pin" and "it has to behave > > that way on pin assertion". Our use cases do not meet the need > > of further runtime configuration change. > > What is the use case? I just have an external power button connected to that pin, it works either with warm reset and cold-reset-except-ldo12. Moreover the default behavior is cold reset and not reset-disabled. Anyway I thought it was useful for other people to add a property selecting behavior for that pin too as was done for WDOG_B. That's why I mainly duplicated the logic. If there is a pin adding a reset source it's a good point to provide a way to access the register bits related to this signal. > > Sorry, you did not bring any further argument why this is board > specific. And please don't explain how probing works, but address the > problem here: why type of reset is specific to board design. To me it is > OS policy. > Why reset type is specific to board design? I'm sorry but I don't know what you mean, as said my intention was to enlarge the number of configurable bits in pca9450 register space hoping this would be useful for someone. All I can say is that is specific to board design for the same reason the wdog_b- reset type was specific to board design. Thank you for your time, fabio > Best regards, > Krzysztof >
