Hi Saravana, On Tue, Jan 19, 2021 at 10:51 PM Saravana Kannan <saravanak@xxxxxxxxxx> wrote: > On Tue, Jan 19, 2021 at 10:08 AM Saravana Kannan <saravanak@xxxxxxxxxx> wrote: > > On Tue, Jan 19, 2021 at 1:05 AM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote: > > > On Mon, Jan 18, 2021 at 10:19 PM Saravana Kannan <saravanak@xxxxxxxxxx> wrote: > > > > On Mon, Jan 18, 2021 at 11:16 AM Geert Uytterhoeven > > > > <geert@xxxxxxxxxxxxxx> wrote: > > > > > On Mon, Jan 18, 2021 at 6:59 PM Marc Zyngier <maz@xxxxxxxxxx> wrote: > > > > > > On 2021-01-18 17:39, Geert Uytterhoeven wrote: > > > > > > > On Fri, Dec 18, 2020 at 4:34 AM Saravana Kannan <saravanak@xxxxxxxxxx> > > > > > > > wrote: > > > > > > >> Cyclic dependencies in some firmware was one of the last remaining > > > > > > >> reasons fw_devlink=on couldn't be set by default. Now that cyclic > > > > > > >> dependencies don't block probing, set fw_devlink=on by default. > > > > > > >> > > > > > > >> Setting fw_devlink=on by default brings a bunch of benefits > > > > > > >> (currently, > > > > > > >> only for systems with device tree firmware): > > > > > > >> * Significantly cuts down deferred probes. > > > > > > >> * Device probe is effectively attempted in graph order. > > > > > > >> * Makes it much easier to load drivers as modules without having to > > > > > > >> worry about functional dependencies between modules (depmod is still > > > > > > >> needed for symbol dependencies). > > > > > > >> > > > > > > >> If this patch prevents some devices from probing, it's very likely due > > > > > > >> to the system having one or more device drivers that "probe"/set up a > > > > > > >> device (DT node with compatible property) without creating a struct > > > > > > >> device for it. If we hit such cases, the device drivers need to be > > > > > > >> fixed so that they populate struct devices and probe them like normal > > > > > > >> device drivers so that the driver core is aware of the devices and > > > > > > >> their > > > > > > >> status. See [1] for an example of such a case. > > > > > > >> > > > > > > >> [1] - > > > > > > >> https://lore.kernel.org/lkml/CAGETcx9PiX==mLxB9PO8Myyk6u2vhPVwTMsA5NkD-ywH5xhusw@xxxxxxxxxxxxxx/ > > > > > > >> Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx> > > > > > > > > > > > > > > Shimoda-san reported that next-20210111 and later fail to boot > > > > > > > on Renesas R-Car Gen3 platforms. No output is seen, unless earlycon > > > > > > > is enabled. > > > > > > > > > > > > > > I have bisected this to commit e590474768f1cc04 ("driver core: Set > > > > > > > fw_devlink=on by default"). > > > > > > > > > > > > There is a tentative patch from Saravana here[1], which works around > > > > > > some issues on my RK3399 platform, and it'd be interesting to find > > > > > > out whether that helps on your system. > > > > > > > > > > > > Thanks, > > > > > > > > > > > > M. > > > > > > > > > > > > [1] > > > > > > https://lore.kernel.org/r/20210116011412.3211292-1-saravanak@xxxxxxxxxx > > > > > > > > > > Thanks for the suggestion, but given no devices probe (incl. GPIO > > > > > providers), I'm afraid it won't help. [testing] Indeed. > > > > > > > > > > With the debug prints in device_links_check_suppliers enabled, and > > > > > some postprocessing, I get: > > > > > > > > > > 255 supplier e6180000.system-controller not ready > > > > > 9 supplier fe990000.iommu not ready > > > > > 9 supplier fe980000.iommu not ready > > > > > 6 supplier febd0000.iommu not ready > > > > > 6 supplier ec670000.iommu not ready > > > > > 3 supplier febe0000.iommu not ready > > > > > 3 supplier e7740000.iommu not ready > > > > > 3 supplier e6740000.iommu not ready > > > > > 3 supplier e65ee000.usb-phy not ready > > > > > 3 supplier e6570000.iommu not ready > > > > > 3 supplier e6054000.gpio not ready > > > > > 3 supplier e6053000.gpio not ready > > > > > > > > > > As everything is part of a PM Domain, the (lack of the) system controller > > > > > must be the culprit. What's wrong with it? It is registered very early in > > > > > the boot: > > > > > > > > > > [ 0.142096] rcar_sysc_pd_init:442: of_genpd_add_provider_onecell() returned 0 > > > > > > > Looks like you found the important logs. Can you please enable all > > > > these logs and send the early con logs as an attachment (so I don't > > > > need to deal with lines getting wrapped)? > > > > 1. The ones in device_links_check_suppliers() > > > > 2. The ones in device_link_add() > > > > 3. initcall_debug=1 > > > > > > I have attached[*] the requested log. > > > > > > > That should help us figure out what's going on. Also, what's the DT > > > > that corresponds to one of the boards that see this issue? > > > > > > arch/arm64/boot/dts/renesas/r8a77951-salvator-xs.dts > > > > > > > Lastly, can you please pick up these 3 patches (some need clean up > > > > before they merge) to make sure it's not an issue being worked on from > > > > other bug reports? > > > > https://lore.kernel.org/lkml/20210116011412.3211292-1-saravanak@xxxxxxxxxx/ > > > > https://lore.kernel.org/lkml/20210115210159.3090203-1-saravanak@xxxxxxxxxx/ > > > > https://lore.kernel.org/lkml/20201218210750.3455872-1-saravanak@xxxxxxxxxx/ > > > > > > > > I have a strong hunch the 2nd one will fix your issues. fw_devlink can > > > > handle cyclic dependencies now (it basically reverts to > > > > fw_devlink=permissive mode for devices in the cycle), but it needs to > > > > "see" all the dependencies to know there's a cycle. So want to make > > > > sure it "sees" the "gpios" binding used all over some of the Renesas > > > > DT files. > > > > > > These patches don't help. > > > The 2nd one actually introduces a new failure: > > > > > > OF: /soc/i2c@e66d8000/gpio@20/pcie-sata-switch-hog: could not get > > > #gpio-cells for /cpus/cpu@102 > > > > > > Note that my issues don't seem to be GPIO-related at all. > I took a look at your logs. It looks like your guess is right. It's at > least one of the issues. > > You'll need to convert drivers/soc/renesas/rcar-sysc.c into a platform > driver. You already have a platform device created for it. So just go > ahead and probe it with a platform driver. See what Marek did here > [1]. > > You probably had to implement it as an "initcall based driver" > because you had to play initcall chicken to make sure the PD hardware > was initialized before the consumers. With fw_devlink=on you won't > have to worry about that. As an added benefit of implementing a proper > platform driver, you can actually implement runtime PM now, your > suspend/resume would be more robust, etc. On R-Car H1, the system controller driver needs to be active before secondary CPU setup, hence the early_initcall(). platform_bus_init() is called after that, so this is gonna need a split initialization. Or a dummy platform driver to make devlinks think everything is fine ;-) So basically all producer DT drivers not using a platform (or e.g. i2c) driver are now broken? Including all clock drivers using CLK_OF_DECLARE()? $ git grep -L "\<[a-z0-9]*_driver\>" -- $(git grep -l "\.compatible\>") | wc -l 249 (includes false positives) I doubt they'll all get fixed for v5.12, as we're already at rc4... Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
