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Date:   Tue, 24 May 2022 15:15:09 -0500
From:   Bjorn Helgaas <helgaas@kernel.org>
To:     Kishon Vijay Abraham I <kishon@ti.com>
Cc:     Jyri Sarha <jyri.sarha@iki.fi>, Tomi Valkeinen <tomba@kernel.org>,
        Rob Herring <robh@kernel.org>, linux-pci@vger.kernel.org
Subject: PCI: keystone: ks_pcie_v3_65_add_bus()
Message-ID: <20220524201509.GA257154@bhelgaas>
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Not sure whether anybody cares about the keystone driver any more.  It
seems basically unmaintained after 57e1d8206e48 ("MAINTAINERS: move
Murali Karicheri to credits") [1].

Anyway, ks_pcie_v3_65_add_bus() [2] looks unusual to me.  It's an
.add_bus() method that is called whenever we create a new PCI bus:

  ks_pcie_v3_65_add_bus(...)
  {
    ks_pcie_set_dbi_mode
    dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 1)
    dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, SZ_4K - 1)
    ks_pcie_clear_dbi_mode(ks_pcie)
    dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, ks_pcie->app.start)
  }

This seems like something that should be done when the Root Port is
enumerated, not when we set up its secondary bus.  Maybe somewhere in
ks_pcie_host_init() or ks_pcie_config_msi_irq()?

I don't think we should use .add_bus() unless it's actually something
related to adding a bus.

[1] https://git.kernel.org/linus/57e1d8206e48
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/pci/controller/dwc/pci-keystone.c?id=v5.18#n452