[PATCH v2 09/11] PCI: mvebu: Update comment for PCI_EXP_LNKCAP register on emulated bridge

From: Pali Rohár
Date: Tue Jan 04 2022 - 10:39:01 EST


Reason for clearing this bit is because mvebu hw returns incorrectly this bit set to 1.

Signed-off-by: Pali Rohár <pali@xxxxxxxxxx>
---
drivers/pci/controller/pci-mvebu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index 94ef00b6d697..1aac65977b97 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -546,8 +546,8 @@ mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,

case PCI_EXP_LNKCAP:
/*
- * PCIe requires the clock power management capability to be
- * hard-wired to zero for downstream ports
+ * PCIe requires that the Clock Power Management capability bit
+ * is hard-wired to zero for downstream ports but HW returns 1.
*/
*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP) &
~PCI_EXP_LNKCAP_CLKPM;
--
2.20.1