Hi, Daniel > Subject: Re: [PATCH V15 RESEND 5/5] arm64: dts: imx: add i.MX8QXP thermal > support > > On 22/02/2020 00:53, Anson Huang wrote: > > Hi, Daniel > > > > [ ... ] > > >>> + > >>> + thermal_zones: thermal-zones { > >>> + cpu-thermal0 { > >>> + polling-delay-passive = <250>; > >>> + polling-delay = <2000>; > >>> + thermal-sensors = <&tsens IMX_SC_R_SYSTEM>; > >>> + trips { > >>> + cpu_alert0: trip0 { > >>> + temperature = <107000>; > >>> + hysteresis = <2000>; > >>> + type = "passive"; > >>> + }; > >> > >> May be you can add a 'hot' trip point before 'critical' for future > >> use before reaching the emergency shutdown. > > > > The 'passive' trip is actually the 'hot' trip point you mentioned, and > > I have combined it to below cooling map which will throttle cpu-freq when > passive (hot) point is reached. > > We all use 'passive' as 'hot' alarm and trigger cpu-freq throttle on i.MX > platforms. > > Sorry, I'm not sure to get the point. A 'hot' trip point is not a 'passive' trip > point. The 'hot' trip point is a critical temperature and a notification is raised > [1][2]. > > It is the last chance for the system to do something before the next trip point > 'critical' is reached and where an emergency shutdown is done. > > The 'passive' trip point is the target temperature for mitigation in a normal > situation when the system is loaded. Ah, now I understand your point, as all i.MX SoCs ONLY support passive and critical point, and never support the notification of hot trip point, so I think it should be OK to leave i.MX8QXP same as other i.MX SoCs, if we plan to support hot trip point notification, I will cut another patch for all i.MX SoCs, does it make sense to you? If yes, please help review the V16 patch set I sent out. thanks again for review, Anson > > [1] > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgit.ker > nel.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Ftorvalds%2Flinux.git%2F > tree%2Fdrivers%2Fthermal%2Fthermal_core.c%23n288&data=02%7C01 > %7Canson.huang%40nxp.com%7C2a1422c3cb0f46c3b13308d7b76c198c%7C > 686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637179547223360051&a > mp;sdata=fRmsFbCVFdv3VwFEqp1sSHxt2rucQ33yYnnaPE5gs1g%3D&res > erved=0 > [2] > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgit.ker > nel.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Ftorvalds%2Flinux.git%2F > tree%2Fdrivers%2Fthermal%2Fthermal_core.c%23n420&data=02%7C01 > %7Canson.huang%40nxp.com%7C2a1422c3cb0f46c3b13308d7b76c198c%7C > 686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637179547223360051&a > mp;sdata=QEiwQcL8FZKg6Rs7y9h9XKvFf%2FlVeo20MwKTiqUbMwA%3D&am > p;reserved=0 > > > > > -- > > <https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww. > linaro.org%2F&data=02%7C01%7Canson.huang%40nxp.com%7C2a1422 > c3cb0f46c3b13308d7b76c198c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C > 0%7C0%7C637179547223360051&sdata=xT2UtNHHA826aziV1aUmPXpa > Bnq7dBm%2FJPFG4S2%2F5qQ%3D&reserved=0> Linaro.org │ Open > source software for ARM SoCs > > Follow Linaro: > <https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww. > facebook.com%2Fpages%2FLinaro&data=02%7C01%7Canson.huang%4 > 0nxp.com%7C2a1422c3cb0f46c3b13308d7b76c198c%7C686ea1d3bc2b4c6fa9 > 2cd99c5c301635%7C0%7C0%7C637179547223360051&sdata=eSr89jm2 > Qxzpi2bX%2BN%2FchizrkF372ypyLgv5%2BuI82Ic%3D&reserved=0> > Facebook | > <https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Ftwitte > r.com%2F%23!%2Flinaroorg&data=02%7C01%7Canson.huang%40nxp.c > om%7C2a1422c3cb0f46c3b13308d7b76c198c%7C686ea1d3bc2b4c6fa92cd99 > c5c301635%7C0%7C0%7C637179547223360051&sdata=cRydP%2FJpfuD > uZFXUivk6F4At1lc%2FsOHdSzDDnDtDOug%3D&reserved=0> Twitter | > <https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww. > linaro.org%2Flinaro- > blog%2F&data=02%7C01%7Canson.huang%40nxp.com%7C2a1422c3cb0 > f46c3b13308d7b76c198c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0 > %7C637179547223360051&sdata=wlwlbrLGXt%2Fdpuvw2xpCToiAIweud > QDvLc8x0kgJOoQ%3D&reserved=0> Blog