Commit fd6e6e38 authored by Maciej W. Rozycki's avatar Maciej W. Rozycki Committed by Bjorn Helgaas
Browse files

PCI/ASPM: Avoid unnecessary pcie_link_state use 

[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: default avatarMaciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent b1689799

drivers/pci/pcie/aspm.c

+7 −8
Original line number Diff line number Diff line
@@ -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 */