Commit b8162653 authored by Klaus Kudielka's avatar Klaus Kudielka Committed by Bjorn Helgaas
Browse files

PCI: mvebu: Fix use of for_each_of_range() iterator 



5da3d94a ("PCI: mvebu: Use for_each_of_range() iterator for parsing
"ranges"") simplified code by using the for_each_of_range() iterator, but
it broke PCI enumeration on Turris Omnia (and probably other mvebu
targets).

Issue #1:

To determine range.flags, of_pci_range_parser_one() uses bus->get_flags(),
which resolves to of_bus_pci_get_flags(), which already returns an
IORESOURCE bit field, and NOT the original flags from the "ranges"
resource.

Then mvebu_get_tgt_attr() attempts the very same conversion again.  Remove
the misinterpretation of range.flags in mvebu_get_tgt_attr(), to restore
the intended behavior.

Issue #2:

The driver needs target and attributes, which are encoded in the raw
address values of the "/soc/pcie/ranges" resource. According to
of_pci_range_parser_one(), the raw values are stored in range.bus_addr and
range.parent_bus_addr, respectively. range.cpu_addr is a translated version
of range.parent_bus_addr, and not relevant here.

Use the correct range structure member, to extract target and attributes.
This restores the intended behavior.

Fixes: 5da3d94a ("PCI: mvebu: Use for_each_of_range() iterator for parsing "ranges"")
Reported-by: default avatarJan Palus <jpalus@fastmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220479


Signed-off-by: default avatarKlaus Kudielka <klaus.kudielka@gmail.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Tested-by: default avatarTony Dinh <mibodhi@gmail.com>
Tested-by: default avatarJan Palus <jpalus@fastmail.com>
Link: https://patch.msgid.link/20250907102303.29735-1-klaus.kudielka@gmail.com
parent 8f5ae30d

drivers/pci/controller/pci-mvebu.c

+4 −17
Original line number Diff line number Diff line
@@ -1168,12 +1168,6 @@ static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev, 
	return devm_ioremap_resource(&pdev->dev, &port->regs);

}



#define DT_FLAGS_TO_TYPE(flags)       (((flags) >> 24) & 0x03)

#define    DT_TYPE_IO                 0x1

#define    DT_TYPE_MEM32              0x2

#define DT_CPUADDR_TO_TARGET(cpuaddr) (((cpuaddr) >> 56) & 0xFF)

#define DT_CPUADDR_TO_ATTR(cpuaddr)   (((cpuaddr) >> 48) & 0xFF)



static int mvebu_get_tgt_attr(struct device_node *np, int devfn,

			      unsigned long type,

			      unsigned int *tgt,
@@ -1189,19 +1183,12 @@ static int mvebu_get_tgt_attr(struct device_node *np, int devfn, 
		return -EINVAL;



	for_each_of_range(&parser, &range) {

		unsigned long rtype;

		u32 slot = upper_32_bits(range.bus_addr);



		if (DT_FLAGS_TO_TYPE(range.flags) == DT_TYPE_IO)

			rtype = IORESOURCE_IO;

		else if (DT_FLAGS_TO_TYPE(range.flags) == DT_TYPE_MEM32)

			rtype = IORESOURCE_MEM;

		else

			continue;



		if (slot == PCI_SLOT(devfn) && type == rtype) {

			*tgt = DT_CPUADDR_TO_TARGET(range.cpu_addr);

			*attr = DT_CPUADDR_TO_ATTR(range.cpu_addr);

		if (slot == PCI_SLOT(devfn) &&

		    type == (range.flags & IORESOURCE_TYPE_BITS)) {

			*tgt = (range.parent_bus_addr >> 56) & 0xFF;

			*attr = (range.parent_bus_addr >> 48) & 0xFF;

			return 0;

		}

	}