[PATCH 4/5] PCI: wait device ready after pci_pm_reset()

Sinan Kaya okaya at codeaurora.org
Sat Sep 23 17:16:57 PDT 2017


Rev 3.1 Sec 2.3.1 Request Handling Rules says a device can issue CRS
following a D3hot->D0 transition. Add pci_dev_wait() call with 1 second
timeout to see if device is available before returning.

Signed-off-by: Sinan Kaya <okaya at codeaurora.org>
---
 drivers/pci/pci.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index fd4a3b6..074adf9 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3963,6 +3963,7 @@ static int pci_af_flr(struct pci_dev *dev, int probe)
  */
 static int pci_pm_reset(struct pci_dev *dev, int probe)
 {
+	unsigned int delay = dev->d3_delay;
 	u16 csr;
 
 	if (!dev->pm_cap || dev->dev_flags & PCI_DEV_FLAGS_NO_PM_RESET)
@@ -3988,7 +3989,10 @@ static int pci_pm_reset(struct pci_dev *dev, int probe)
 	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
 	pci_dev_d3_sleep(dev);
 
-	return 0;
+	if (delay < pci_pm_d3_delay)
+		delay = pci_pm_d3_delay;
+
+	return pci_dev_wait(dev, "PM D3->D0", delay, 1000);
 }
 
 void pci_reset_secondary_bus(struct pci_dev *dev)
-- 
1.9.1




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