Hello Leigh,
On Tue, 29 Jan 2019 15:36:56 +0000
Leigh Brown <leigh@xxxxxxxxxxxxx> wrote:
> Apologies, I use webmail. I have attached two files with the results
> from running lspci -vvv -xxx
Thanks, that was very useful. I believe the issue comes from the fact
that your PCIe device has prefetchable BARs, while none of the 5 PCIe
devices I have here has prefetchable BARs. The pci-mvebu driver doesn't
support such BARs, but the change to the common PCI bridge emulation
logic made the prefetchable memory base / limit register read-write
while they were read-only before.
To verify this hypothesis, could you apply the following patch (on top
of 4.20), and see if it solves the problem ? Thanks!
This is probably not the right/correct fix, but it will at least allow
to verify that the problem is understood correctly.
Thomas
diff --git a/drivers/pci/pci-bridge-emul.c b/drivers/pci/pci-bridge-emul.c
index 129738362d90..f99b80c19809 100644
--- a/drivers/pci/pci-bridge-emul.c
+++ b/drivers/pci/pci-bridge-emul.c
@@ -142,11 +142,7 @@ const static struct pci_bridge_reg_behavior pci_regs_behavior[] = {
},
[PCI_PREF_MEMORY_BASE / 4] = {
- /* The high 12-bits of pref mem base/limit are RW */
- .rw = GENMASK(31, 20) | GENMASK(15, 4),
-
- /* The low four bits of pref mem base/limit are RO */
- .ro = GENMASK(19, 16) | GENMASK(3, 0),
+ .ro = ~0,
},
[PCI_PREF_BASE_UPPER32 / 4] = {
--
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
