[PATCH 5/5] PCI: st: disable IO support

One Thousand Gnomes gnomes at lxorguk.ukuu.org.uk
Wed Dec 17 06:01:31 PST 2014


On Wed, 17 Dec 2014 11:34:46 +0100
Gabriel FERNANDEZ <gabriel.fernandez at st.com> wrote:

> sti SoCs PCIe IPs are built around DesignWare IP Core.
> But in these SoCs, PCIe IP doesn't support IO.
> By default, when no IO space is provided, a default one is assigned.
> 
> Add an empty IO resource to the bus, and disable IO by default.

As a point of PCI pedantry I don't think this is quite sufficient. PCI
has a weird corner case where I/O resources are implied rather than
allocated.

For IDE/SATA you may need to something like

	if (class == PCI_CLASS_STORAGE_IDE) {
		u8 progif;
		pci_read_config_byte(dev, PCI_CLASS_PROG, &progif);
		progif |= 5;
		pci_write_config_byte(dev, PCI_CLASS_PROG, &progif);
	}

so that any adapter is kicked out of legacy mode and doesn't get implied
I/O resources and interrupts. I don't know if that case matters for your
usage.





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