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Date:   Mon, 20 Sep 2021 10:14:04 +0100
Message-ID: <871r5jwqw3.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Kishon Vijay Abraham I <kishon@ti.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Bjorn Helgaas <bhelgaas@google.com>,
        <linux-kernel@vger.kernel.org>, <linux-pci@vger.kernel.org>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        <lokeshvutla@ti.com>
Subject: Re: [PATCH 0/3] PCI/gic-v3-its: Add support for same ITS device ID for multiple PCIe devices
In-Reply-To: <20210920064133.14115-1-kishon@ti.com>
References: <20210920064133.14115-1-kishon@ti.com>
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On Mon, 20 Sep 2021 07:41:30 +0100,
Kishon Vijay Abraham I <kishon@ti.com> wrote:
> 
> AM64 has an issue in that it doesn't trigger interrupt if the address
> in the *pre_its_window* is not aligned to 8-bytes (this is due to an
> invalid bridge configuration in HW).
> 
> This means there will not be interrupts for devices with PCIe
> requestor ID 0x1, 0x3, 0x5..., as the address in the pre-ITS window
> would be 4 (1 << 2), 12 (3 << 2), 20 (5 << 2) respectively which are
> not aligned to 8-bytes.
> 
> The DT binding has specified "msi-map-mask" using which multiple PCIe
> devices could be made to use the same ITS device ID.
> 
> Add support in irq-gic-v3-its-pci-msi.c for such cases where multiple
> PCIe devices are using the same ITS device ID.
> 
> Kishon Vijay Abraham I (3):
>   PCI: Add support in pci_walk_bus() to invoke callback matching RID
>   PCI: Export find_pci_root_bus()
>   irqchip/gic-v3-its: Include "msi-map-mask" for calculating nvecs
> 
>  drivers/irqchip/irq-gic-v3-its-pci-msi.c | 21 ++++++++++++++++++++-
>  drivers/pci/bus.c                        | 13 +++++++++----
>  drivers/pci/host-bridge.c                |  3 ++-
>  include/linux/pci.h                      |  8 ++++++--
>  4 files changed, 37 insertions(+), 8 deletions(-)

What I don't see in this series is how you address the other part of
the problem, which is your reuse of the Socionext hack. Please post a
complete series addressing all the issues for this HW.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.