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PCI/ASPM: Avoid unnecessary pcie_link_state use

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[bhelgaas: extract from expose patch, reorder to clean up before exposing]
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306110229010.64925@angie.orcam.me.uk
Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Maciej W. Rozycki 2023-06-14 15:09:06 -05:00 committed by Bjorn Helgaas
parent b168979977
commit fd6e6e38eb
1 changed files with 7 additions and 8 deletions
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15
drivers/pci/pcie/aspm.c
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@ -193,30 +193,29 @@ 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 bool pcie_retrain_link(struct pci_dev *pdev)
{
struct pci_dev *parent = link->pdev;
unsigned long end_jiffies;
u16 lnkctl;
u16 lnksta;
pcie_capability_read_word(parent, PCI_EXP_LNKCTL, &lnkctl);
pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnkctl);
lnkctl |= PCI_EXP_LNKCTL_RL;
pcie_capability_write_word(parent, PCI_EXP_LNKCTL, lnkctl);
if (parent->clear_retrain_link) {
pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnkctl);
if (pdev->clear_retrain_link) {
/*
* Due to an erratum in some devices the Retrain Link bit
* needs to be cleared again manually to allow the link
* training to succeed.
*/
lnkctl &= ~PCI_EXP_LNKCTL_RL;
pcie_capability_write_word(parent, PCI_EXP_LNKCTL, lnkctl);
pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnkctl);
}
/* Wait for link training end. Break out after waiting for timeout */
end_jiffies = jiffies + LINK_RETRAIN_TIMEOUT;
do {
pcie_capability_read_word(parent, PCI_EXP_LNKSTA, &lnksta);
pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnksta);
if (!(lnksta & PCI_EXP_LNKSTA_LT))
break;
msleep(1);
@ -290,7 +289,7 @@ 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))
if (pcie_retrain_link(link->pdev))
return;
/* Training failed. Restore common clock configurations */