On Tue, 15 Oct 2024 at 18:47, Claudiu <claudiu.beznea@xxxxxxxxx> wrote: > > From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx> > > Hi, > > Watchdog device available on RZ/G3S SoC is part of a software-controlled > power domain. The watchdog driver implements struct > watchdog_ops::restart() handler which is called in atomic context via > this call chain: > > kernel_restart() -> > machine_restart() -> > do_kernel_restart() -> > atomic_notifier_call_chain() -> > watchdog_restart_notifier() > rzg2l_wdt_restart() > > When the rzg2l_wdt_restart() is called it may happen that the watchdog > clocks to be disabled and the associated power domain to be off. > Accessing watchdog registers in this state leads to aborts and system > blocks. > > To solve this issue the watchdog power domain was marked as IRQ safe > as well as watchdog device (as proposed by Ulf Hansson). Along with > it the clk_prepare_enable() calls from the watchdog restart() handler > were removed and all is based now on pm_runtime_resume_and_get() > as explained in patch 03/03. > > Series contains also power domain driver changes to be able to > register the watchdog PM domain as an IRQ safe one. > > Initial RFC series for solving this issue was posted at [1]. > > It is safe to merge watchdog and PM domain driver changes though > different trees. > > Thank you, > Claudiu Beznea > > [1] https://lore.kernel.org/all/20240619120920.2703605-1-claudiu.beznea.uj@xxxxxxxxxxxxxx/ > > Changes in v4: > - in patch 1/1, function rzg2l_cpg_pd_setup(): > -- call rzg2l_cpg_power_on() unconditionally of governor > -- drop governor's parameter and decide what governor to use based on > always_on > - collected tags > > Changes in v3: > - added patch "clk: renesas: rzg2l-cpg: Move PM domain power on in > rzg2l_cpg_pd_setup()" > - addressed review comments > - collected tags > - per-patch changes are listed in individual patches > > Changes in v2: > - adjusted patch title for patch 02/03 > - adjusted description for patch 03/03 along with comment > from code > > Changes since RFC: > - dropped patches 01/03, 02/03 from RFC > - adjusted power domain driver to be able to register the > watchdog PM domain as an IRQ safe one > - drop clock prepare approach from watchdog driver presented in RFC > and rely only on pm_runtime_resume_and_get() > - mark the watchdog device as IRQ safe > > > Claudiu Beznea (4): > clk: renesas: rzg2l-cpg: Move PM domain power on in > rzg2l_cpg_pd_setup() > clk: renesas: rzg2l-cpg: Use GENPD_FLAG_* flags instead of local ones > clk: renesas: r9a08g045: Mark the watchdog and always-on PM domains as > IRQ safe > watchdog: rzg2l_wdt: Power on the watchdog domain in the restart > handler > > drivers/clk/renesas/r9a08g045-cpg.c | 52 +++++++++++------------------ > drivers/clk/renesas/rzg2l-cpg.c | 41 ++++++++++++----------- > drivers/clk/renesas/rzg2l-cpg.h | 10 ++---- > drivers/watchdog/rzg2l_wdt.c | 20 +++++++++-- > 4 files changed, 63 insertions(+), 60 deletions(-) > > -- > 2.39.2 > For the series, feel free to add: Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Kind regards Uffe
