On Wednesday, January 17, 2018 10:14:23 AM CET Geert Uytterhoeven wrote: > Hi Rafael, > > On Mon, Jan 15, 2018 at 5:17 PM, Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote: > > On Mon, Jan 15, 2018 at 3:26 PM, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote: > >> On 15 January 2018 at 14:22, Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote: > > > > [cut] > > > >>> > >>> I did miss a small difference in topology: in pm/linux-next, H3 has DMA > >>> enabled for SCIF2, while M3 hasn't (yet). > >>> With DMA enabled on M3, it fails in the same way. > >>> > >>> As genpd_resume_noirq() no longer calls pm_runtime_force_resume(), > >>> rcar_dmac_runtime_resume() is no longer called, and the DMAC's registers > >>> are no longer reinitialized after system resume, breaking the serial port. > >> > >> In drivers/dma/sh/rcar-dmac.c, I would try to replace the below line: > >> SET_SYSTEM_SLEEP_PM_OPS(rcar_dmac_sleep_suspend, rcar_dmac_sleep_resume) > >> > >> with: > >> SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) > > > > Yes, that probably is the least intrusive thing that can be done to > > address the issue. > > > >> in case that may be too early to suspend the dma device (which is > >> rather common for dma devices) then try; > >> > >> SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) > > > > Good suggestion, and I would go straight for it anyway. > > > > Geert, can you try if this works, please? > > Works. Both using SET_SYSTEM_SLEEP_PM_OPS() and > SET_LATE_SYSTEM_SLEEP_PM_OPS(). But given this is a DMA engine > driver, I'd settle for the latter. > > And I did verify doing so doesn't break the system without the patch > in $subject. > > Thanks! > > Will send a patch... Thank you!
