[PATCH 2/2] PCI/ASPM: Avoid L0s and L1 on Freescale Root Ports

Bjorn Helgaas <[email protected]>
Newsgroups gmane.linux.kernel.pci,gmane.linux.ports.ppc64.devel,gmane.linux.debian.ports.powerpc,gmane.linux.kernel
Message-ID <[email protected]>
From: Bjorn Helgaas <[email protected]>

Christian reported that f3ac2ff14834 ("PCI/ASPM: Enable all ClockPM and
ASPM states for devicetree platforms") broke booting on the A-EON X5000.

Fixes: f3ac2ff14834 ("PCI/ASPM: Enable all ClockPM and ASPM states for devicetree platforms")
Fixes: df5192d9bb0e ("PCI/ASPM: Enable only L0s and L1 for devicetree platforms"
)
Reported-by: Christian Zigotzky <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bjorn Helgaas <[email protected]>
---
 drivers/pci/quirks.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 214ed060ca1b..44e780718953 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -2525,6 +2525,18 @@ static void quirk_disable_aspm_l0s_l1(struct pci_dev *dev)
  */
 DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ASMEDIA, 0x1080, quirk_disable_aspm_l0s_l1);
 
+/*
+ * Remove ASPM L0s and L1 support from cached copy of Link Capabilities so
+ * aspm.c won't try to enable them.
+ */
+static void quirk_disable_aspm_l0s_l1_cap(struct pci_dev *dev)
+{
+	dev->lnkcap &= ~PCI_EXP_LNKCAP_ASPM_L0S;
+	dev->lnkcap &= ~PCI_EXP_LNKCAP_ASPM_L1;
+	pci_info(dev, "ASPM: L0s L1 removed from Link Capabilities to work around device defect\n");
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_FREESCALE, 0x0451, quirk_disable_aspm_l0s_l1_cap);
+
 /*
  * Some Pericom PCIe-to-PCI bridges in reverse mode need the PCIe Retrain
  * Link bit cleared after starting the link retrain process to allow this
-- 
2.43.0
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.