Re: [PATCH 0/6] fsl-mc: Move fsl_over to device MSI

[Sascha Bischoff <Sascha.Bischoff@arm.com>]

On Wed, 2026-02-18 at 13:51 +0000, Marc Zyngier wrote:
> Over the past few years, I have become increasingly annoyed by this
> sort of messages in my boot log:
> 
> [    0.067861] fsl-mc MSI: ITS@0x100100040000 domain created
> [    0.073352] fsl-mc MSI: ITS@0x100100060000 domain created
> [    0.078841] fsl-mc MSI: ITS@0x100100080000 domain created
> [    0.084328] fsl-mc MSI: ITS@0x1001000a0000 domain created
> [    0.089815] fsl-mc MSI: ITS@0x1001000c0000 domain created
> [    0.095303] fsl-mc MSI: ITS@0x1001000e0000 domain created
> [    0.100792] fsl-mc MSI: ITS@0x100100100000 domain created
> [    0.106281] fsl-mc MSI: ITS@0x100100120000 domain created
> 
> While this is useful on fsl-mc systems, this is completely irrelevant
> on 99.99999% of the arm64 machines, which know nothing about the
> Freescale stuff. Including all of my machine -- bar *one*.
> 
> Global MSI domains such as the above have been obsoleted for the past
> two years, but nobody at NXP seems to have got the message.
> 
> The obvious solution is to delete some code! While my first port of
> call would be to just 'git rm -r drivers/bus/fsl-mc' (only kidding!),
> a less invasive solution is to drag that code into the present times.
> Which is what this series is doing by converting the whole thing to
> device MSI, reusing the platform MSI infrastructure instead of
> duplicating it.
> 
> This results in the expected cleanup, and kills the last user of the
> non-device-MSI stuff on arm64. You're welcome.
> 
> Marc Zyngier (6):
>   fsl-mc: Remove MSI domain propagation to sub-devices
>   fsl_mc: Add minimal infrastructure to use platform MSI
>   irqchip/gic-v3-its: Add fsl_mc device plumbing to the msi-parent
>     handling
>   fsl_mc: Switch over to per-device platform MSI
>   fsl_mc: Remove legacy MSI implementation
>   platform-msi: Remove stale comment
> 
>  drivers/base/platform-msi.c                 |   4 -
>  drivers/bus/fsl-mc/dprc-driver.c            |  14 +-
>  drivers/bus/fsl-mc/fsl-mc-bus.c             |   4 +-
>  drivers/bus/fsl-mc/fsl-mc-msi.c             | 142 +++--------------
>  drivers/bus/fsl-mc/fsl-mc-private.h         |   2 +-
>  drivers/irqchip/Kconfig                     |   6 -
>  drivers/irqchip/Makefile                    |   1 -
>  drivers/irqchip/irq-gic-its-msi-parent.c    |   7 +-
>  drivers/irqchip/irq-gic-v3-its-fsl-mc-msi.c | 168 ------------------
> --
>  include/linux/fsl/mc.h                      |   6 +-
>  10 files changed, 33 insertions(+), 321 deletions(-)
>  delete mode 100644 drivers/irqchip/irq-gic-v3-its-fsl-mc-msi.c
> 

I have tested this series (applied to 6.19) with a SolidRun ClearFog CX
LX2 (LX2160A-based), and can confirm that the MSIs are working as I'd
expect them to. Therefore:

Tested-by: Sascha Bischoff <sascha.bischoff@arm.com>

Thanks,
Sascha