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PCI/ASPM: Factor out waiting for link training to complete

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Move code polling for the Link Training bit to clear into a function of its
own.

[bhelgaas: reorder to clean up before exposing to PCI core]
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306111605060.64925@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 2023-06-11 18:19:49 +01:00 committed by Bjorn Helgaas
parent fd6e6e38eb
commit 3c0ec896a4
1 changed files with 23 additions and 11 deletions
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34
drivers/pci/pcie/aspm.c
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@ -193,12 +193,32 @@ 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 pci_dev *pdev)
/**
* pcie_wait_for_link_status - Wait for link training end
* @pdev: Device whose link to wait for.
*
* Return TRUE if successful, or FALSE if training has not completed
* within LINK_RETRAIN_TIMEOUT jiffies.
*/
static bool pcie_wait_for_link_status(struct pci_dev *pdev)
{
unsigned long end_jiffies;
u16 lnkctl;
u16 lnksta;
end_jiffies = jiffies + LINK_RETRAIN_TIMEOUT;
do {
pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnksta);
if (!(lnksta & PCI_EXP_LNKSTA_LT))
break;
msleep(1);
} while (time_before(jiffies, end_jiffies));
return !(lnksta & PCI_EXP_LNKSTA_LT);
}
static bool pcie_retrain_link(struct pci_dev *pdev)
{
u16 lnkctl;
pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnkctl);
lnkctl |= PCI_EXP_LNKCTL_RL;
pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnkctl);
@ -212,15 +232,7 @@ static bool pcie_retrain_link(struct pci_dev *pdev)
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(pdev, PCI_EXP_LNKSTA, &lnksta);
if (!(lnksta & PCI_EXP_LNKSTA_LT))
break;
msleep(1);
} while (time_before(jiffies, end_jiffies));
return !(lnksta & PCI_EXP_LNKSTA_LT);
return pcie_wait_for_link_status(pdev);
}
/*