[PATCH 15/15] PCI: mvebu: Fix support for DEVCAP2, DEVCTL2 and LNKCTL2 registers on emulated bridge

Pali Rohár
2021-11-25T12:49:13Z

Armada XP and new hardware supports access to DEVCAP2, DEVCTL2 and LNKCTL2
configuration registers of PCIe core via PCIE_CAP_PCIEXP. So export them
via emulated software root bridge.

Pre-XP hardware does not support these registers and returns zeros.

Signed-off-by: Pali Rohár <pali@kernel.org>
Fixes: 1f08673eef12 ("PCI: mvebu: Convert to PCI emulated bridge config space")
Cc: stable@vger.kernel.org
---
drivers/pci/controller/pci-mvebu.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)

diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index 798cf5cff8be..9a17bab4019f 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -571,6 +571,18 @@ mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
*value = mvebu_readl(port, PCIE_RC_RTSTA);
break;

+ case PCI_EXP_DEVCAP2:
+ *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP2);
+ break;
+
+ case PCI_EXP_DEVCTL2:
+ *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2);
+ break;
+
+ case PCI_EXP_LNKCTL2:
+ *value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2);
+ break;
+
default:
return PCI_BRIDGE_EMUL_NOT_HANDLED;
}
@@ -683,6 +695,17 @@ mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
if (new & PCI_EXP_RTSTA_PME)
mvebu_writel(port, ~PCIE_INT_PM_PME, PCIE_INT_CAUSE_OFF);
break;
+
+ case PCI_EXP_DEVCTL2:
+ mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2);
+ break;
+
+ case PCI_EXP_LNKCTL2:
+ mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2);
+ break;
+
+ default:
+ break;
}
}

--
2.20.1