[PATCH 5.16 0800/1039] PCI: mvebu: Do not modify PCI IO type bits in conf_write

From: Greg Kroah-Hartman
Date: Mon Jan 24 2022 - 19:16:29 EST


From: Pali Rohár <pali@xxxxxxxxxx>

[ Upstream commit 2cf150216e5b5619d7c25180ccf2cc8ac7bebc13 ]

PCI IO type bits are already initialized in mvebu_pci_bridge_emul_init()
function and only when IO support is enabled. These type bits are read-only
and pci-bridge-emul.c code already does not allow to modify them from upper
layers.

When IO support is disabled then all IO registers should be read-only and
return zeros. Therefore do not modify PCI IO type bits in
mvebu_pci_bridge_emul_base_conf_write() callback.

Link: https://lore.kernel.org/r/20211125124605.25915-8-pali@xxxxxxxxxx
Fixes: 1f08673eef12 ("PCI: mvebu: Convert to PCI emulated bridge config space")
Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/pci/controller/pci-mvebu.c | 7 -------
1 file changed, 7 deletions(-)

diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index e6d63ad4d23b8..beae555b06bbc 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -497,13 +497,6 @@ mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge,
}

case PCI_IO_BASE:
- /*
- * We keep bit 1 set, it is a read-only bit that
- * indicates we support 32 bits addressing for the
- * I/O
- */
- conf->iobase |= PCI_IO_RANGE_TYPE_32;
- conf->iolimit |= PCI_IO_RANGE_TYPE_32;
mvebu_pcie_handle_iobase_change(port);
break;

--
2.34.1