This is a note to let you know that I've just added the patch titled
PCI/ASPM: Return 0 or -ETIMEDOUT from pcie_retrain_link()
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-aspm-return-0-or-etimedout-from-pcie_retrain_lin.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit d86d8d098cd05f8e3a2b27084b97e5028bbcff81
Author: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Date: Tue Jun 20 14:44:55 2023 -0500
PCI/ASPM: Return 0 or -ETIMEDOUT from pcie_retrain_link()
[ Upstream commit f5297a01ee805d7fa569d288ed65fc0f9ac9b03d ]
"pcie_retrain_link" is not a question with a true/false answer, so "bool"
isn't quite the right return type. Return 0 for success or -ETIMEDOUT if
the retrain failed. No functional change intended.
[bhelgaas: based on Ilpo's patch below]
Link: https://lore.kernel.org/r/20230502083923.34562-1-ilpo.jarvinen@xxxxxxxxxxxxxxx
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Stable-dep-of: e7e39756363a ("PCI/ASPM: Avoid link retraining race")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index d8d27b11b48c4..3197ac6dda35b 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -200,7 +200,7 @@ static void pcie_clkpm_cap_init(struct pcie_link_state *link, int blacklist)
link->clkpm_disable = blacklist ? 1 : 0;
}
-static bool pcie_retrain_link(struct pcie_link_state *link)
+static int pcie_retrain_link(struct pcie_link_state *link)
{
struct pci_dev *parent = link->pdev;
unsigned long end_jiffies;
@@ -227,7 +227,9 @@ static bool pcie_retrain_link(struct pcie_link_state *link)
break;
msleep(1);
} while (time_before(jiffies, end_jiffies));
- return !(reg16 & PCI_EXP_LNKSTA_LT);
+ if (reg16 & PCI_EXP_LNKSTA_LT)
+ return -ETIMEDOUT;
+ return 0;
}
/*
@@ -296,15 +298,15 @@ static void pcie_aspm_configure_common_clock(struct pcie_link_state *link)
reg16 &= ~PCI_EXP_LNKCTL_CCC;
pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16);
- if (pcie_retrain_link(link))
- return;
+ if (pcie_retrain_link(link)) {
- /* Training failed. Restore common clock configurations */
- pci_err(parent, "ASPM: Could not configure common clock\n");
- list_for_each_entry(child, &linkbus->devices, bus_list)
- pcie_capability_write_word(child, PCI_EXP_LNKCTL,
+ /* Training failed. Restore common clock configurations */
+ pci_err(parent, "ASPM: Could not configure common clock\n");
+ list_for_each_entry(child, &linkbus->devices, bus_list)
+ pcie_capability_write_word(child, PCI_EXP_LNKCTL,
child_reg[PCI_FUNC(child->devfn)]);
- pcie_capability_write_word(parent, PCI_EXP_LNKCTL, parent_reg);
+ pcie_capability_write_word(parent, PCI_EXP_LNKCTL, parent_reg);
+ }
}
/* Convert L0s latency encoding to ns */
