diff mbox series

[v9,09/14] PCI: Factor our waiting for link training end

Message ID alpine.DEB.2.21.2306111605060.64925@angie.orcam.me.uk (mailing list archive)
State Not Applicable
Headers show
Series pci: Work around ASMedia ASM2824 PCIe link training failures | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Guessed tree name to be net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 40 this patch: 40
netdev/cc_maintainers success CCed 2 of 2 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 39 this patch: 39
netdev/checkpatch warning WARNING: msleep < 20ms can sleep for up to 20ms; see Documentation/timers/timers-howto.rst
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Maciej W. Rozycki June 11, 2023, 5:19 p.m. UTC 
Move code polling for the Link Training bit to clear into a function of 
its own.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
---
New change in v9.
---
 drivers/pci/pci.c |   37 ++++++++++++++++++++++++-------------
 1 file changed, 24 insertions(+), 13 deletions(-)

linux-pcie-wait-for-link-status.diff
diff mbox series

Patch

Index: linux-macro/drivers/pci/pci.c
===================================================================
--- linux-macro.orig/drivers/pci/pci.c
+++ linux-macro/drivers/pci/pci.c
@@ -4850,6 +4850,28 @@  static int pci_pm_reset(struct pci_dev *
 }
 
 /**
+ * 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 PCIE_LINK_RETRAIN_TIMEOUT_MS milliseconds.
+ */
+static bool pcie_wait_for_link_status(struct pci_dev *pdev)
+{
+	unsigned long end_jiffies;
+	u16 lnksta;
+
+	end_jiffies = jiffies + msecs_to_jiffies(PCIE_LINK_RETRAIN_TIMEOUT_MS);
+	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);
+}
+
+/**
  * pcie_wait_for_link_delay - Wait until link is active or inactive
  * @pdev: Bridge device
  * @active: waiting for active or inactive?
@@ -4916,14 +4938,11 @@  bool pcie_wait_for_link(struct pci_dev *
  * pcie_retrain_link - Request a link retrain and wait for it to complete
  * @pdev: Device whose link to retrain.
  *
- * Return TRUE if successful, or FALSE if training has not completed
- * within PCIE_LINK_RETRAIN_TIMEOUT_MS milliseconds.
+ * Return TRUE if successful, or FALSE if training has not completed.
  */
 bool pcie_retrain_link(struct pci_dev *pdev)
 {
-	unsigned long end_jiffies;
 	u16 lnkctl;
-	u16 lnksta;
 
 	pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnkctl);
 	lnkctl |= PCI_EXP_LNKCTL_RL;
@@ -4938,15 +4957,7 @@  bool pcie_retrain_link(struct pci_dev *p
 		pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnkctl);
 	}
 
-	/* Wait for link training end. Break out after waiting for timeout. */
-	end_jiffies = jiffies + msecs_to_jiffies(PCIE_LINK_RETRAIN_TIMEOUT_MS);
-	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);
 }
 
 /*