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 e11ebafaf7749883a9632cd1e99a36cbce6821f0..a4a1b369853b7bf5d112fd93fc738d8224b4cbb1 100644 (file)
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -128,6 +128,23 @@ void pci_disable_ats(struct pci_dev *dev)
 }
 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

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 54343aa5b30a548f11e66f266373e53e07fcc323..97fff785e97e7027f7d54563186db969075a2558 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -965,6 +965,7 @@ void pci_restore_state(struct pci_dev *dev)
 
        /* PCI Express register must be restored first */
        pci_restore_pcie_state(dev);
+       pci_restore_ats_state(dev);
 
        /*
         * The Base Address register should be programmed before the command

diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 3b6e4ed306b636cbbea2146e56a9c506fb7d89ea..1009a5e88e533f37736710895ffc6ba5194f0498 100644 (file)
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -251,6 +251,14 @@ struct pci_sriov {
        u8 __iomem *mstate;     /* VF Migration State Array */
 };
 
+#ifdef CONFIG_PCI_ATS
+extern void pci_restore_ats_state(struct pci_dev *dev);
+#else
+static inline void pci_restore_ats_state(struct pci_dev *dev)
+{
+}
+#endif /* CONFIG_PCI_ATS */
+
 #ifdef CONFIG_PCI_IOV
 extern int pci_iov_init(struct pci_dev *dev);
 extern void pci_iov_release(struct pci_dev *dev);