pci: Disable I/O forwarding during autoconfiguration if unsupported
If U-Boot does not have any I/O resource for assignment then disable I/O
forwarding in PCI bridge autoconfiguration code. Default initial state of
PCI bridge IO registers is unspecified, therefore they can be in enabled if
U-Boot does not touch them.
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/drivers/pci/pci_auto.c b/drivers/pci/pci_auto.c
index 7e6ee54..6e5ed19 100644
--- a/drivers/pci/pci_auto.c
+++ b/drivers/pci/pci_auto.c
@@ -265,6 +265,14 @@
(pci_io->bus_lower & 0xffff0000) >> 16);
cmdstat |= PCI_COMMAND_IO;
+ } else {
+ /* Disable I/O if unsupported */
+ dm_pci_write_config8(dev, PCI_IO_BASE, 0xf0 | io_32);
+ dm_pci_write_config8(dev, PCI_IO_LIMIT, 0x0 | io_32);
+ if (io_32 == PCI_IO_RANGE_TYPE_32) {
+ dm_pci_write_config16(dev, PCI_IO_BASE_UPPER16, 0x0);
+ dm_pci_write_config16(dev, PCI_IO_LIMIT_UPPER16, 0x0);
+ }
}
/* Enable memory and I/O accesses, enable bus master */