PCI: support PCIe ARI capability

This patch adds support for PCI Express Alternative Routing-ID
Interpretation (ARI) capability.

The ARI capability extends the Function Number field of the PCI Express
Endpoint by reusing the Device Number which is otherwise hardwired to 0.
With ARI, an Endpoint can have up to 256 functions.

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/include/linux/pci_regs.h b/include/linux/pci_regs.h
index 450684f7eaac..eb6686b88f9a 100644
--- a/include/linux/pci_regs.h
+++ b/include/linux/pci_regs.h
@@ -419,6 +419,10 @@
 #define  PCI_EXP_RTCTL_CRSSVE   0x10    /* CRS Software Visibility Enable */
 #define PCI_EXP_RTCAP           30      /* Root Capabilities */
 #define PCI_EXP_RTSTA           32      /* Root Status */
+#define PCI_EXP_DEVCAP2         36      /* Device Capabilities 2 */
+#define  PCI_EXP_DEVCAP2_ARI    0x20    /* Alternative Routing-ID */
+#define PCI_EXP_DEVCTL2         40      /* Device Control 2 */
+#define  PCI_EXP_DEVCTL2_ARI    0x20    /* Alternative Routing-ID */
 
 /* Extended Capabilities (PCI-X 2.0 and Express) */
 #define PCI_EXT_CAP_ID(header)          (header & 0x0000ffff)
@@ -429,6 +433,7 @@
 #define PCI_EXT_CAP_ID_VC       2
 #define PCI_EXT_CAP_ID_DSN      3
 #define PCI_EXT_CAP_ID_PWR      4
+#define PCI_EXT_CAP_ID_ARI      14
 
 /* Advanced Error Reporting */
 #define PCI_ERR_UNCOR_STATUS    4       /* Uncorrectable Error Status */
@@ -536,5 +541,14 @@
 #define HT_CAPTYPE_GEN3         0xD0    /* Generation 3 hypertransport configuration */
 #define HT_CAPTYPE_PM           0xE0    /* Hypertransport powermanagement configuration */
 
+/* Alternative Routing-ID Interpretation */
+#define PCI_ARI_CAP             0x04    /* ARI Capability Register */
+#define  PCI_ARI_CAP_MFVC       0x0001  /* MFVC Function Groups Capability */
+#define  PCI_ARI_CAP_ACS        0x0002  /* ACS Function Groups Capability */
+#define  PCI_ARI_CAP_NFN(x)     (((x) >> 8) & 0xff) /* Next Function Number */
+#define PCI_ARI_CTRL            0x06    /* ARI Control Register */
+#define  PCI_ARI_CTRL_MFVC      0x0001  /* MFVC Function Groups Enable */
+#define  PCI_ARI_CTRL_ACS       0x0002  /* ACS Function Groups Enable */
+#define  PCI_ARI_CTRL_FG(x)     (((x) >> 4) & 7) /* Function Group */
 
 #endif /* LINUX_PCI_REGS_H */