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authorStefan Mätje <stefan.maetje@esd.eu>2019-03-29 20:07:34 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-05-25 19:26:53 +0300
commit1c38a7b6845ed04e2fb0cf08d70c1a12ab753c41 (patch)
tree66b1986c236205ae2a6f9c1a7ec68dc27df59d97 /drivers/pci/pcie
parent0e21ba0f991378773b0e194c63d9703c25d5d470 (diff)
downloadlinux-1c38a7b6845ed04e2fb0cf08d70c1a12ab753c41.tar.xz
PCI: Factor out pcie_retrain_link() function
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>
Diffstat (limited to 'drivers/pci/pcie')
-rw-r--r--drivers/pci/pcie/aspm.c40
1 files changed, 24 insertions, 16 deletions
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 6643a7bc381c..e83f438b036b 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -172,6 +172,29 @@ static void pcie_clkpm_cap_init(struct pcie_link_state *link, int blacklist)
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, &reg16);
+ 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, &reg16);
+ 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
@@ -181,7 +204,6 @@ static void pcie_aspm_configure_common_clock(struct pcie_link_state *link)
{
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;
/*
@@ -221,21 +243,7 @@ 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);
- /* 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, &reg16);
- 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 */