> Subject: RE: [PATCH] watchdog: rzg2l_wdt: Issue a reset before we put > the PM clocks > > > > > -----Original Message----- > > From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> > > Sent: 14 November 2022 19:04 > > To: Biju Das <biju.das.jz@xxxxxxxxxxxxxx> > > Cc: Prabhakar <prabhakar.csengg@xxxxxxxxx>; Geert Uytterhoeven > > <geert+renesas@xxxxxxxxx>; Wim Van Sebroeck <wim@linux- > watchdog.org>; > > Guenter Roeck <linux@xxxxxxxxxxxx>; Philipp Zabel > > <p.zabel@xxxxxxxxxxxxxx>; linux- watchdog@xxxxxxxxxxxxxxx; > > linux-kernel@xxxxxxxxxxxxxxx; linux-renesas- soc@xxxxxxxxxxxxxxx; > > Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>; Prabhakar Mahadev > > Lad <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> > > Subject: Re: [PATCH] watchdog: rzg2l_wdt: Issue a reset before we > put > > the PM clocks > > > > Hi Biju, > > > > On Mon, Nov 14, 2022 at 7:42 PM Biju Das > <biju.das.jz@xxxxxxxxxxxxxx> wrote: > > > > -----Original Message----- > > > > From: Prabhakar <prabhakar.csengg@xxxxxxxxx> > > > > Sent: 14 November 2022 18:09 > > > > To: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>; Wim Van > Sebroeck > > > > <wim@xxxxxxxxxxxxxxxxxx>; Guenter Roeck <linux@xxxxxxxxxxxx>; > > > > Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>; > > > > linux-watchdog@xxxxxxxxxxxxxxx > > > > Cc: linux-kernel@xxxxxxxxxxxxxxx; > > > > linux-renesas-soc@xxxxxxxxxxxxxxx; > > > > Prabhakar <prabhakar.csengg@xxxxxxxxx>; Biju Das > > > > <biju.das.jz@xxxxxxxxxxxxxx>; Fabrizio Castro > > > > <fabrizio.castro.jz@xxxxxxxxxxx>; Prabhakar Mahadev Lad > > > > <prabhakar.mahadev- lad.rj@xxxxxxxxxxxxxx> > > > > Subject: [PATCH] watchdog: rzg2l_wdt: Issue a reset before we > put > > > > the PM clocks > > > > > > > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> > > > > > > > > On RZ/Five SoC it was observed that setting timeout (to say 1 > sec) > > > > wouldn't reset the system. To fix this we make sure we issue a > > > > reset before putting the PM clocks to make sure the registers > have > > > > been > > cleared. > > > > > > > > While at it re-used rzg2l_wdt_stop() in rzg2l_wdt_set_timeout() > as > > > > we were calling the same functions here. > > > > > > > > Signed-off-by: Lad Prabhakar > > > > <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> > > > > --- > > > > Note, > > > > - This patch has been tested on RZ/G2L, RZ/V2M and RZ/Five. > > > > - My initial investigation showed adding the delay after > > > > pm_runtime_get_sync() > > > > also fixed this issue. > > > > - Do I need add the fixes tag ? what should be the operation > PUT- > > > > >RESET/RESET->PUT? > > > > > > It looks like timing issue, None of the previous devices are > > > affected by > > this. > > > > To me it looks like the device must be clocked for the reset signal > to > > be propagated? > > Yep, provide clk supply for a device, then apply reset. Maybe we need to make it consistent by taking care of [1] Current patch: CLK ON -> apply Reset for V2M. [1]: Apply Reset -> CLK ON for V2M. [1] https://lore.kernel.org/linux-renesas-soc/CAMuHMdUWbT6VArm9B56VE0yUYWCTm=3vMGrrONSv9cdsQQnhpg@xxxxxxxxxxxxxx/T/#mdb78503524a8f4207f59a40f7ff573e210656988 Cheers, Biju
