Rob Herring <robh@xxxxxxxxxx> writes:
> No other host driver sets the PCI_MSI_FLAGS_ENABLE bit, so it must not
> be necessary. If it is, a comment is needed.
Yeah, but git blame directly points to:
75cb8d20c112 ("PCI: imx: Enable MSI from downstream components")
Which has a pretty long explanation. The relevant bit probably being:
... on i.MX6, the MSI Enable bit controls delivery of MSI interrupts
from components below the Root Port.
So it seems a little rash to just remove the code.
cheers
> Cc: Richard Zhu <hongxing.zhu@xxxxxxx>
> Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> Cc: Fabio Estevam <festevam@xxxxxxxxx>
> Cc: NXP Linux Team <linux-imx@xxxxxxx>
> Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> drivers/pci/controller/dwc/pci-imx6.c | 8 --------
> 1 file changed, 8 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index 5cf1ef12fb9b..7dd137d62dca 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -1002,7 +1002,6 @@ static int imx6_pcie_probe(struct platform_device *pdev)
> struct resource *dbi_base;
> struct device_node *node = dev->of_node;
> int ret;
> - u16 val;
>
> imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
> if (!imx6_pcie)
> @@ -1167,13 +1166,6 @@ static int imx6_pcie_probe(struct platform_device *pdev)
> if (ret < 0)
> return ret;
>
> - if (pci_msi_enabled()) {
> - u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
> - val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
> - val |= PCI_MSI_FLAGS_ENABLE;
> - dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
> - }
> -
> return 0;
> }
>
> --
> 2.25.1
