PCI: support the ATS capability
The PCIe ATS capability makes the Endpoint be able to request the
DMA address translation from the IOMMU and cache the translation
in the device side, thus alleviate IOMMU pressure and improve the
hardware performance in the I/O virtualization environment.
Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/include/linux/pci_regs.h b/include/linux/pci_regs.h
index e4d08c1..c03189c 100644
--- a/include/linux/pci_regs.h
+++ b/include/linux/pci_regs.h
@@ -501,6 +501,7 @@
#define PCI_EXT_CAP_ID_DSN 3
#define PCI_EXT_CAP_ID_PWR 4
#define PCI_EXT_CAP_ID_ARI 14
+#define PCI_EXT_CAP_ID_ATS 15
#define PCI_EXT_CAP_ID_SRIOV 16
/* Advanced Error Reporting */
@@ -619,6 +620,15 @@
#define PCI_ARI_CTRL_ACS 0x0002 /* ACS Function Groups Enable */
#define PCI_ARI_CTRL_FG(x) (((x) >> 4) & 7) /* Function Group */
+/* Address Translation Service */
+#define PCI_ATS_CAP 0x04 /* ATS Capability Register */
+#define PCI_ATS_CAP_QDEP(x) ((x) & 0x1f) /* Invalidate Queue Depth */
+#define PCI_ATS_MAX_QDEP 32 /* Max Invalidate Queue Depth */
+#define PCI_ATS_CTRL 0x06 /* ATS Control Register */
+#define PCI_ATS_CTRL_ENABLE 0x8000 /* ATS Enable */
+#define PCI_ATS_CTRL_STU(x) ((x) & 0x1f) /* Smallest Translation Unit */
+#define PCI_ATS_MIN_STU 12 /* shift of minimum STU block */
+
/* Single Root I/O Virtualization */
#define PCI_SRIOV_CAP 0x04 /* SR-IOV Capabilities */
#define PCI_SRIOV_CAP_VFM 0x01 /* VF Migration Capable */