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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Last-TLS-Session-Version: TLSv1.3 X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.39 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.8 at phobos.denx.de X-Virus-Status: Clean Hi Tom, > On Tue, Sep 09, 2025 at 06:44:45PM +0300, Svyatoslav Ryhel wrote: > > =D0=B2=D1=82, 9 =D0=B2=D0=B5=D1=80. 2025=E2=80=AF=D1=80. =D0=BE 18:39 T= om Rini =D0=BF=D0=B8=D1=88=D0=B5: =20 > > > > > > On Tue, Sep 09, 2025 at 02:26:19PM +0300, Svyatoslav Ryhel wrote: > > > =20 > > > > =D0=B2=D1=82, 9 =D0=B2=D0=B5=D1=80. 2025=E2=80=AF=D1=80. =D0=BE 13:= 15 =C5=81ukasz Majewski > > > > =D0=BF=D0=B8=D1=88=D0=B5: =20 > > > > > > > > > > Hi Svyatoslav, > > > > > =20 > > > > > > =D0=BF=D0=BD, 8 =D0=B2=D0=B5=D1=80. 2025=E2=80=AF=D1=80. =D0=BE= 15:41 =C5=81ukasz Majewski > > > > > > =D0=BF=D0=B8=D1=88=D0=B5: =20 > > > > > > > > > > > > > > Hi Svyatoslav, > > > > > > > =20 > > > > > > > > =D0=B2=D1=82, 26 =D1=81=D0=B5=D1=80=D0=BF. 2025=E2=80=AF=D1= =80. =D0=BE 12:39 Lukasz Majewski > > > > > > > > =D0=BF=D0=B8=D1=88=D0=B5: =20 > > > > > > > > > > > > > > > > > > The Tegra30 SoC is a bit special, as it doesn't have > > > > > > > > > the separate IP block to provide watchdog > > > > > > > > > functionality. > > > > > > > > > > > > > > > > > > Instead, timer IP block allows such functionality > > > > > > > > > when properly configured. > > > > > > > > > > > > > > > > > > As in the tegra30.dtsi there is a timer node, which > > > > > > > > > "covers" all timers, with 'nvidia,tegra30-timer' > > > > > > > > > compatibility it was necessary to manually bind > > > > > > > > > U-Boot's WDT driver (based on WDT_UCLASS). > > > > > > > > > > > > > > > > > > Signed-off-by: Lukasz Majewski > > > > > > > > > --- > > > > > > > > > drivers/timer/tegra-timer.c | 18 ++++++++++++++++++ > > > > > > > > > 1 file changed, 18 insertions(+) > > > > > > > > > =20 > > > > > > > > > > > > > > > > What is the practical application for this diver in > > > > > > > > therms of Tegra and U-Boot overall? =20 > > > > > > > > > > > > > > You have the WDT functionality working. It uses the same > > > > > > > DTS bindings as ones used in Linux. =20 > > > > > > > > > > > > Why do we need WDT for Tegra in U-Boot at all? =20 > > > > > > > > > > Can you correct me if I draw wrong conclusion - you ask why > > > > > Tegra needs to support watchdog in u-boot bootloader ? > > > > > =20 > > > > > > It is not used and has > > > > > > no practical application. > > > > > > =20 > > > > > > > > > > Yes, it has ... > > > > > > > > > > Customer has number of Tegra30 colibri modules in the field. > > > > > They want to switch to u-boot + linux kernel BSP. > > > > > > > > > > For their application - it would be welcome if the device > > > > > could reboot and start emergency procedure in the case of not > > > > > being able to start Linux. > > > > > > > > > > The procedure is that we start Watchdog at very early boot - > > > > > then we do have for example 30 seconds to "feed" the Watchdog > > > > > in Linux > > > > > > > > > > When we fail, after watchdog reboot, we can switch to another > > > > > rootfs partition (the A/B scheme of booting) or start > > > > > emergency system.=20 > > > > > > > > So when are you going to submit this board variant? If driver > > > > has no users, it is removed. =20 > > > > > > I assume it would be enabled on colibri_t30_defconfig. > > > =20 > >=20 > > T30 colibri does not need it and does not use it with current > > configuration, hence I am asking about board submission. =20 >=20 > It's a devkit where I'm pretty sure the watchdog exists, so we can > enable it there and be done. Just because it doesn't use it today > doesn't mean it can't use it in the future if we enable it, the "use > watchdog to make sure A/B system configures are stable" is a common > use case. +1 --=20 Best regards, Lukasz Majewski -- Nabla Software Engineering GmbH HRB 40522 Augsburg Phone: +49 821 45592596 E-Mail: office@nabladev.com Geschftsfhrer : Stefano Babic