NTB: NTB-RP support
Add support for Non-Transparent Bridge connected to a PCI-E Root Port on
the remote system (also known as NTB-RP mode). This allows for a NTB
enabled system to be connected to a non-NTB enabled system/slot.
Modifications to the registers and BARs/MWs on the Secondary side by the
remote system are reflected into registers on the Primary side for the
local system. Similarly, modifications of registers and BARs/MWs on
Primary side by the local system are reflected into registers on the
Secondary side for the Remote System. This allows communication between
the 2 sides via these registers and BARs/MWs.
Note: there is not a fix for the Xeon Errata (that was already worked
around in NTB-B2B mode) for NTB-RP mode. Due to this limitation, NTB-RP
will not work on the Secondary side with the Xeon Errata workaround
enabled. To get around this, disable the workaround via the
xeon_errata_workaround=0 modparm. However, this can cause the hang
described in the errata.
Signed-off-by: Jon Mason <jon.mason@intel.com>
diff --git a/drivers/ntb/ntb_regs.h b/drivers/ntb/ntb_regs.h
index 03a66ef..b4f4604 100644
--- a/drivers/ntb/ntb_regs.h
+++ b/drivers/ntb/ntb_regs.h
@@ -46,8 +46,6 @@
* Jon Mason <jon.mason@intel.com>
*/
-#define NTB_LINK_ENABLE 0x0000
-#define NTB_LINK_DISABLE 0x0002
#define NTB_LINK_STATUS_ACTIVE 0x2000
#define NTB_LINK_SPEED_MASK 0x000f
#define NTB_LINK_WIDTH_MASK 0x03f0
@@ -65,6 +63,7 @@
#define SNB_PCICMD_OFFSET 0x0504
#define SNB_DEVCTRL_OFFSET 0x0598
+#define SNB_SLINK_STATUS_OFFSET 0x05A2
#define SNB_LINK_STATUS_OFFSET 0x01A2
#define SNB_PBAR2LMT_OFFSET 0x0000
@@ -147,6 +146,8 @@
#define BWD_LTSSMSTATEJMP_FORCEDETECT (1 << 2)
#define BWD_IBIST_ERR_OFLOW 0x7FFF7FFF
+#define NTB_CNTL_CFG_LOCK (1 << 0)
+#define NTB_CNTL_LINK_DISABLE (1 << 1)
#define NTB_CNTL_BAR23_SNOOP (1 << 2)
#define NTB_CNTL_BAR45_SNOOP (1 << 6)
#define BWD_CNTL_LINK_DOWN (1 << 16)