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Subject[PATCH v2 10/11] PCI: mvebu: Update comment for PCI_EXP_LNKCTL register on emulated bridge
Date
Logic and code for clearing PCI_EXP_LNKCTL_CLKREQ_EN bit is correct, but
comment describing it is misleading. PCI_EXP_LNKCTL_CLKREQ_EN bit should be
hardwired to zero but mvebu hw allows to change it.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
drivers/pci/controller/pci-mvebu.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index 1aac65977b97..dffa330de174 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -663,10 +663,9 @@ mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,

case PCI_EXP_LNKCTL:
/*
- * If we don't support CLKREQ, we must ensure that the
- * CLKREQ enable bit always reads zero. Since we haven't
- * had this capability, and it's dependent on board wiring,
- * disable it for the time being.
+ * PCIe requires that the Enable Clock Power Management bit
+ * is hard-wired to zero for downstream ports but HW allows
+ * to change it.
*/
new &= ~PCI_EXP_LNKCTL_CLKREQ_EN;

--
2.20.1
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