From: Stefan Mätje stefan.maetje@esd.eu
commit 86fa6a344209d9414ea962b1f1ac6ade9dd7563a upstream.
Factor out pcie_retrain_link() to use for Pericom Retrain Link quirk. No functional change intended.
Signed-off-by: Stefan Mätje stefan.maetje@esd.eu Signed-off-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com CC: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/pci/pcie/aspm.c | 40 ++++++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 16 deletions(-)
--- a/drivers/pci/pcie/aspm.c +++ b/drivers/pci/pcie/aspm.c @@ -211,6 +211,29 @@ static void pcie_clkpm_cap_init(struct p link->clkpm_capable = (blacklist) ? 0 : capable; }
+static bool pcie_retrain_link(struct pcie_link_state *link) +{ + struct pci_dev *parent = link->pdev; + unsigned long start_jiffies; + u16 reg16; + + pcie_capability_read_word(parent, PCI_EXP_LNKCTL, ®16); + reg16 |= PCI_EXP_LNKCTL_RL; + pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16); + + /* Wait for link training end. Break out after waiting for timeout */ + start_jiffies = jiffies; + for (;;) { + pcie_capability_read_word(parent, PCI_EXP_LNKSTA, ®16); + if (!(reg16 & PCI_EXP_LNKSTA_LT)) + break; + if (time_after(jiffies, start_jiffies + LINK_RETRAIN_TIMEOUT)) + break; + msleep(1); + } + return !(reg16 & PCI_EXP_LNKSTA_LT); +} + /* * pcie_aspm_configure_common_clock: check if the 2 ends of a link * could use common clock. If they are, configure them to use the @@ -220,7 +243,6 @@ static void pcie_aspm_configure_common_c { int same_clock = 1; u16 reg16, parent_reg, child_reg[8]; - unsigned long start_jiffies; struct pci_dev *child, *parent = link->pdev; struct pci_bus *linkbus = parent->subordinate; /* @@ -260,21 +282,7 @@ static void pcie_aspm_configure_common_c reg16 &= ~PCI_EXP_LNKCTL_CCC; pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16);
- /* Retrain link */ - reg16 |= PCI_EXP_LNKCTL_RL; - pcie_capability_write_word(parent, PCI_EXP_LNKCTL, reg16); - - /* Wait for link training end. Break out after waiting for timeout */ - start_jiffies = jiffies; - for (;;) { - pcie_capability_read_word(parent, PCI_EXP_LNKSTA, ®16); - if (!(reg16 & PCI_EXP_LNKSTA_LT)) - break; - if (time_after(jiffies, start_jiffies + LINK_RETRAIN_TIMEOUT)) - break; - msleep(1); - } - if (!(reg16 & PCI_EXP_LNKSTA_LT)) + if (pcie_retrain_link(link)) return;
/* Training failed. Restore common clock configurations */