From: Bjorn Helgaas <bhelg...@google.com>

Previously we programmed the LTR_L1.2_THRESHOLD in the parent (upstream)
device using the capability pointer of the *child* (downstream) device,
which corrupted some random word of the parent's config space.

Use the parent's L1 SS capability pointer to program its
LTR_L1.2_THRESHOLD.

Fixes: aeda9adebab8 ("PCI/ASPM: Configure L1 substate settings")
Signed-off-by: Bjorn Helgaas <bhelg...@google.com>
CC: sta...@vger.kernel.org      # v4.11+
CC: Rajat Jain <raja...@google.com>
---
 drivers/pci/pcie/aspm.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 46c59afb8355..a378dd9d2473 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -657,7 +657,7 @@ static void pcie_config_aspm_l1ss(struct pcie_link_state 
*link, u32 state)
                                        0xFF00, link->l1ss.ctl1);
 
                /* Program LTR L1.2 threshold in both ports */
-               pci_clear_and_set_dword(parent, dw_cap_ptr + PCI_L1SS_CTL1,
+               pci_clear_and_set_dword(parent, up_cap_ptr + PCI_L1SS_CTL1,
                                        0xE3FF0000, link->l1ss.ctl1);
                pci_clear_and_set_dword(child, dw_cap_ptr + PCI_L1SS_CTL1,
                                        0xE3FF0000, link->l1ss.ctl1);

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