Commit 3c0ec896 authored by Maciej W. Rozycki's avatar Maciej W. Rozycki Committed by Bjorn Helgaas
Browse files

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

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: default avatarMaciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent fd6e6e38

drivers/pci/pcie/aspm.c

+23 −11
Original line number Diff line number Diff line
@@ -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);

}



/*