| Message ID | 20250113112349.801875-1-prabhakar.mahadev-lad.rj@bp.renesas.com |
|---|---|
| Headers | show |
| Series | Add support to retrieve the bootstatus from watchdog for RZ/V2H(P) SoC | expand |
On Mon, Jan 13, 2025 at 11:38:08AM +0000, Biju Das wrote: > Hi Prabhakar, > > > -----Original Message----- > > From: Prabhakar <prabhakar.csengg@gmail.com> > > Sent: 13 January 2025 11:24 > > Subject: [PATCH v3 0/6] Add support to retrieve the bootstatus from watchdog for RZ/V2H(P) SoC > > > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > > > > Hi All, > > > > This patch series adds SYSCON support to retrieve boot status information for RZ/V2H(P) SoC. > > Summary of Changes, > > > > Clock: > > Add syscon compatible support to the CPG block in bindings and > > device trees. > > > > Watchdog: > > Document the renesas,r9a09g057-syscon-wdt-errorrst property. > > Update the watchdog driver to fetch and report boot status via > > Error Reset Registers (CPG_ERROR_RSTm). > > > > Device Tree: > > Add the syscon property to CPG and WDT nodes in R9A09G057 and > > R9A09G047 SoC DTSI. > > > > These changes enable the watchdog driver to identify boot sources like Power-on Reset and Watchdog > > Reset, improving system diagnostics. > > This means that, we should assume U-boot/bootloader should not clear the WDT reset status bit. > > If they clear it, there should be a way to propagate it from u-boot/bootloader to linux, > otherwise, we get wrong bootstatus in linux. > But the clearing of watchdog status by one of the cases: > > 1) u-boot identify the boot source and clear the status bit > 2) u-boot identify the boot source and does not clear the status bit, but linux clear it. > 3) u-boot does not touch WDT status bits, but linux clear it. Sounds like the same problem as this[1]. If that works for you, please comment there. Always better if there is more than 1 user for something "common". Rob [1]https://lore.kernel.org/devicetree-spec/48defa98-9718-4997-86cb-b171187708a6@cherry.de/T/#u
Hi Guenter and Rob, On Tue, Jan 14, 2025 at 8:17 PM Guenter Roeck <linux@roeck-us.net> wrote: > > On 1/14/25 12:03, Rob Herring wrote: > > On Mon, Jan 13, 2025 at 11:38:08AM +0000, Biju Das wrote: > >> Hi Prabhakar, > >> > >>> -----Original Message----- > >>> From: Prabhakar <prabhakar.csengg@gmail.com> > >>> Sent: 13 January 2025 11:24 > >>> Subject: [PATCH v3 0/6] Add support to retrieve the bootstatus from watchdog for RZ/V2H(P) SoC > >>> > >>> From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> > >>> > >>> Hi All, > >>> > >>> This patch series adds SYSCON support to retrieve boot status information for RZ/V2H(P) SoC. > >>> Summary of Changes, > >>> > >>> Clock: > >>> Add syscon compatible support to the CPG block in bindings and > >>> device trees. > >>> > >>> Watchdog: > >>> Document the renesas,r9a09g057-syscon-wdt-errorrst property. > >>> Update the watchdog driver to fetch and report boot status via > >>> Error Reset Registers (CPG_ERROR_RSTm). > >>> > >>> Device Tree: > >>> Add the syscon property to CPG and WDT nodes in R9A09G057 and > >>> R9A09G047 SoC DTSI. > >>> > >>> These changes enable the watchdog driver to identify boot sources like Power-on Reset and Watchdog > >>> Reset, improving system diagnostics. > >> > >> This means that, we should assume U-boot/bootloader should not clear the WDT reset status bit. > >> > >> If they clear it, there should be a way to propagate it from u-boot/bootloader to linux, > >> otherwise, we get wrong bootstatus in linux. > >> But the clearing of watchdog status by one of the cases: > >> > >> 1) u-boot identify the boot source and clear the status bit > >> 2) u-boot identify the boot source and does not clear the status bit, but linux clear it. > >> 3) u-boot does not touch WDT status bits, but linux clear it. > > > > Sounds like the same problem as this[1]. If that works for you, please > > comment there. Always better if there is more than 1 user for something > > "common". > > > > Rob > > > > [1]https://lore.kernel.org/devicetree-spec/48defa98-9718-4997-86cb-b171187708a6@cherry.de/T/#u > > If this ends up being provided through /chosen, it should probably be supported > in the watchdog core. > There wasn't any conclusion on the thread [0]. Can you please recommend how you want me to proceed on this series. [0] https://lore.kernel.org/devicetree-spec/48defa98-9718-4997-86cb-b171187708a6@cherry.de/T/#m2f1c7f5c8166522982cecf9351903ab06ca4f9ee Cheers, Prabhakar
From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Hi All, This patch series adds SYSCON support to retrieve boot status information for RZ/V2H(P) SoC. Summary of Changes, Clock: Add syscon compatible support to the CPG block in bindings and device trees. Watchdog: Document the renesas,r9a09g057-syscon-wdt-errorrst property. Update the watchdog driver to fetch and report boot status via Error Reset Registers (CPG_ERROR_RSTm). Device Tree: Add the syscon property to CPG and WDT nodes in R9A09G057 and R9A09G047 SoC DTSI. These changes enable the watchdog driver to identify boot sources like Power-on Reset and Watchdog Reset, improving system diagnostics. v2->v3 - Updated comment section to mentione there arent any ABI breakages with this patch series. Cheers, Prabhakar Lad Prabhakar (6): dt-bindings: clock: rzv2h-cpg: Add syscon compatible for CPG block arm64: dts: renesas: r9a09g047: Add `syscon` compatible for CPG node arm64: dts: renesas: r9a09g057: Add `syscon` compatible for CPG node dt-bindings: watchdog: renesas: Document `renesas,syscon-cpg-error-rst` property watchdog: rzv2h_wdt: Add support to retrieve the bootstatus information arm64: dts: renesas: r9a09g057: Add `renesas,syscon-cpg-error-rst` property to WDT node .../bindings/clock/renesas,rzv2h-cpg.yaml | 10 +++--- .../bindings/watchdog/renesas,wdt.yaml | 17 +++++++++ arch/arm64/boot/dts/renesas/r9a09g047.dtsi | 2 +- arch/arm64/boot/dts/renesas/r9a09g057.dtsi | 6 +++- drivers/watchdog/rzv2h_wdt.c | 35 +++++++++++++++++++ 5 files changed, 64 insertions(+), 6 deletions(-)