Commit 58c19a14 authored Sep 23, 2015 by Russell King Committed by Bjorn Helgaas Oct 08, 2015

PCI: mvebu: Return zero for reserved or unimplemented config space



PCI requires reads to reserved or unimplemented configuration space to
return zero and complete normally (see PCI r3.0, sec 6.1).  However, the
root port software implementation was returning 0xfffffff and
PCIBIOS_BAD_REGISTER_NUMBER.

Return zero when reading reserved or unimplemented config space.

[bhelgaas: changelog]
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> (Armada XP GP)
Tested-by: Andrew Lunn <andrew@lunn.ch> (Kirkwood DIR665)
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

parent 6ff33f39

drivers/pci/host/pci-mvebu.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -515,8 +515,13 @@ static int mvebu_sw_pci_bridge_read(struct mvebu_pcie_port *port,
		break;

		default:
		*value = 0xffffffff;
		return PCIBIOS_BAD_REGISTER_NUMBER;
		/*
		* PCI defines configuration read accesses to reserved or
		* unimplemented registers to read as zero and complete
		* normally.
		*/
		*value = 0;
		return PCIBIOS_SUCCESSFUL;
		}

		if (size == 2)

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