From b1689799772a6f4180f918b0ff66e264a3db9796 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Sun, 11 Jun 2023 18:19:45 +0100 Subject: [PATCH] PCI/ASPM: Use distinct local vars in pcie_retrain_link() Use separate local variables to hold the respective values retrieved from the Link Control Register and the Link Status Register. Improves readability and it makes it possible for the compiler to detect actual uninitialised use should this code change in the future. [bhelgaas: reorder to clean up before exposing to PCI core] Link: https://lore.kernel.org/r/alpine.DEB.2.21.2306110252260.64925@angie.orcam.me.uk Signed-off-by: Maciej W. Rozycki Signed-off-by: Bjorn Helgaas --- drivers/pci/pcie/aspm.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c index 66d7514..0048c41 100644 --- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -197,30 +197,31 @@ static bool pcie_retrain_link(struct pcie_link_state *link) { struct pci_dev *parent = link->pdev; unsigned long end_jiffies; - u16 reg16; + u16 lnkctl; + u16 lnksta; - pcie_capability_read_word(parent, PCI_EXP_LNKCTL, ®16); - reg16 |= PCI_EXP_LNKCTL_RL; - pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16); + pcie_capability_read_word(parent, PCI_EXP_LNKCTL, &lnkctl); + lnkctl |= PCI_EXP_LNKCTL_RL; + pcie_capability_write_word(parent, PCI_EXP_LNKCTL, lnkctl); if (parent->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. */ - reg16 &= ~PCI_EXP_LNKCTL_RL; - pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16); + lnkctl &= ~PCI_EXP_LNKCTL_RL; + pcie_capability_write_word(parent, 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, ®16); - if (!(reg16 & PCI_EXP_LNKSTA_LT)) + pcie_capability_read_word(parent, PCI_EXP_LNKSTA, &lnksta); + if (!(lnksta & PCI_EXP_LNKSTA_LT)) break; msleep(1); } while (time_before(jiffies, end_jiffies)); - return !(reg16 & PCI_EXP_LNKSTA_LT); + return !(lnksta & PCI_EXP_LNKSTA_LT); } /* -- 2.7.4