PCI: Enable ATS at the device state restore
During S3 or S4 resume or PCI reset, ATS regs aren't restored correctly.
This patch enables ATS at the device state restore if PCI device has ATS
capability.
Signed-off-by: Xudong Hao <xudong.hao@intel.com>
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index e11ebaf..a4a1b36 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -128,6 +128,23 @@
}
EXPORT_SYMBOL_GPL(pci_disable_ats);
+void pci_restore_ats_state(struct pci_dev *dev)
+{
+ u16 ctrl;
+
+ if (!pci_ats_enabled(dev))
+ return;
+ if (!pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ATS))
+ BUG();
+
+ ctrl = PCI_ATS_CTRL_ENABLE;
+ if (!dev->is_virtfn)
+ ctrl |= PCI_ATS_CTRL_STU(dev->ats->stu - PCI_ATS_MIN_STU);
+
+ pci_write_config_word(dev, dev->ats->pos + PCI_ATS_CTRL, ctrl);
+}
+EXPORT_SYMBOL_GPL(pci_restore_ats_state);
+
/**
* pci_ats_queue_depth - query the ATS Invalidate Queue Depth
* @dev: the PCI device
