Hi Saravana, On 04.02.2021 22:31, Saravana Kannan wrote: > On Thu, Feb 4, 2021 at 3:52 AM Marek Szyprowski > <m.szyprowski@xxxxxxxxxxx> wrote: >> On 21.01.2021 23:57, Saravana Kannan wrote: >>> This allows fw_devlink to create device links between consumers of an >>> interrupt and the supplier of the interrupt. >>> >>> Cc: Marc Zyngier <maz@xxxxxxxxxx> >>> Cc: Kevin Hilman <khilman@xxxxxxxxxxxx> >>> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> >>> Reviewed-by: Rob Herring <robh@xxxxxxxxxx> >>> Reviewed-by: Thierry Reding <treding@xxxxxxxxxx> >>> Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx> >>> Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx> >> This patch landed some time ago in linux-next as commit 4104ca776ba3 >> ("of: property: Add fw_devlink support for interrupts"). It breaks MMC >> host controller operation on ARM Juno R1 board (the mmci@50000 device >> defined in arch/arm64/boot/dts/arm/juno-motherboard.dtsi). I didn't > I grepped around and it looks like the final board file is this or > whatever includes it? > arch/arm64/boot/dts/arm/juno-base.dtsi The final board file is arch/arm64/boot/dts/arm/juno-r1.dts > This patch just finds the interrupt-parent and then tries to use that > as a supplier if "interrupts" property is listed. But the only > interrupt parent I can see is: > gic: interrupt-controller@2c010000 { > compatible = "arm,gic-400", "arm,cortex-a15-gic"; > > And the driver uses IRQCHIP_DECLARE() and hence should be pretty much > a NOP since those suppliers are never devices and are ignored. > $ git grep "arm,gic-400" -- drivers/ > drivers/irqchip/irq-gic.c:IRQCHIP_DECLARE(gic_400, "arm,gic-400", gic_of_init); > > This doesn't make any sense. Am I looking at the right files? Am I > missing something? Okay, I've added displaying a list of deferred devices when mounting rootfs fails and got following items: Deferred devices: 18000000.ethernet platform: probe deferral - supplier bus@8000000:motherboard-bus not ready 1c050000.mmci amba: probe deferral - supplier bus@8000000:motherboard-bus not ready 1c1d0000.gpio amba: probe deferral - supplier bus@8000000:motherboard-bus not ready 2b600000.iommu platform: probe deferral - wait for supplier scpi-power-domains 7ff50000.hdlcd platform: probe deferral - wait for supplier scpi-clk 7ff60000.hdlcd platform: probe deferral - wait for supplier scpi-clk 1c060000.kmi amba: probe deferral - supplier bus@8000000:motherboard-bus not ready 1c070000.kmi amba: probe deferral - supplier bus@8000000:motherboard-bus not ready 1c170000.rtc amba: probe deferral - supplier bus@8000000:motherboard-bus not ready 1c0f0000.wdt amba: probe deferral - supplier bus@8000000:motherboard-bus not ready gpio-keys Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) I don't see the 'bus@8000000:motherboard-bus' on the deferred devices list, so it looks that device core added a link to something that is not a platform device... Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland