[PATCH 5.15 072/262] PCI: mvebu: Fix support for PCI_EXP_DEVCTL on emulated bridge

From: Greg Kroah-Hartman
Date: Mon Mar 07 2022 - 05:01:54 EST


From: Pali Rohár <pali@xxxxxxxxxx>

[ Upstream commit ecae073e393e65ee7be7ebf3fdd5258ab99f1636 ]

Comment in Armada 370 functional specification is misleading.
PCI_EXP_DEVCTL_*RE bits are supported and configures receiving of error
interrupts.

Link: https://lore.kernel.org/r/20211125124605.25915-14-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 | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)

diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index 3563301e772ae..6100608e6413e 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -498,9 +498,7 @@ mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
break;

case PCI_EXP_DEVCTL:
- *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL) &
- ~(PCI_EXP_DEVCTL_URRE | PCI_EXP_DEVCTL_FERE |
- PCI_EXP_DEVCTL_NFERE | PCI_EXP_DEVCTL_CERE);
+ *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
break;

case PCI_EXP_LNKCAP:
@@ -590,13 +588,6 @@ mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,

switch (reg) {
case PCI_EXP_DEVCTL:
- /*
- * Armada370 data says these bits must always
- * be zero when in root complex mode.
- */
- new &= ~(PCI_EXP_DEVCTL_URRE | PCI_EXP_DEVCTL_FERE |
- PCI_EXP_DEVCTL_NFERE | PCI_EXP_DEVCTL_CERE);
-
mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
break;

--
2.34.1