> -----Original Message----- > From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> > Sent: 15 November 2022 08:11 > To: Biju Das <biju.das.jz@xxxxxxxxxxxxxx> > Cc: Prabhakar <prabhakar.csengg@xxxxxxxxx>; Wim Van Sebroeck > <wim@xxxxxxxxxxxxxxxxxx>; 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 Tue, Nov 15, 2022 at 8:48 AM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> > wrote: > > > > -----Original Message----- > > > > From: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> On Mon, Nov 14, > > > > 2022 at 7:42 PM Biju Das > > > <biju.das.jz@xxxxxxxxxxxxxx> wrote: > > > > > > From: Prabhakar <prabhakar.csengg@xxxxxxxxx> 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. > > Yes, that would also simplify that patch: just add the call to reset? Fabrizio previously told me, CLK ON -> apply Reset does not work for RZ/V2M reboot use case. Regards, Biju
