NTB: Enable Snoop on Primary Side

Enable Snoop from Primary to Secondary side on BAR23 and BAR45 on all
TLPs.  Previously, Snoop was only enabled from Secondary to Primary
side.  This can have a performance improvement on some workloads.

Also, make the code more obvious about how the link is being enabled.

Signed-off-by: Jon Mason <jon.mason@intel.com>

diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c
index 391c377a5d3860cb64497df8f03fd7783b3239f0..80505aeecf9e13b40b225048f0630e3e239c0edf 100644 (file)
--- a/drivers/ntb/ntb_hw.c
+++ b/drivers/ntb/ntb_hw.c
@@ -1316,10 +1316,16 @@ static void ntb_hw_link_up(struct ntb_device *ndev)
 {
        if (ndev->conn_type == NTB_CONN_TRANSPARENT)
                ntb_link_event(ndev, NTB_LINK_UP);
 {
        if (ndev->conn_type == NTB_CONN_TRANSPARENT)
                ntb_link_event(ndev, NTB_LINK_UP);

-       else
+       else {
+               u32 ntb_cntl;
+

                /* Let's bring the NTB link up */
                /* Let's bring the NTB link up */

-               writel(NTB_CNTL_BAR23_SNOOP | NTB_CNTL_BAR45_SNOOP,
-                      ndev->reg_ofs.lnk_cntl);
+               ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+               ntb_cntl &= ~(NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK);
+               ntb_cntl |= NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP;
+               ntb_cntl |= NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP;
+               writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+       }

 }
 
 static void ntb_hw_link_down(struct ntb_device *ndev)
 }
 
 static void ntb_hw_link_down(struct ntb_device *ndev)


@@ -1333,8 +1339,9 @@ static void ntb_hw_link_down(struct ntb_device *ndev)
 
        /* Bring NTB link down */
        ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
 
        /* Bring NTB link down */
        ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);

-       ntb_cntl &= ~(NTB_CNTL_BAR23_SNOOP | NTB_CNTL_BAR45_SNOOP);
-       ntb_cntl |= NTB_CNTL_LINK_DISABLE;
+       ntb_cntl &= ~(NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP);
+       ntb_cntl &= ~(NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP);
+       ntb_cntl |= NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK;

        writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
 }
 
        writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
 }
 

diff --git a/drivers/ntb/ntb_regs.h b/drivers/ntb/ntb_regs.h
index a689f1ca630fadd725522f8a9cf0b1a207ea48b6..9774506419d75ba1a5dc08a5f0e4d52e90d33ad7 100644 (file)
--- a/drivers/ntb/ntb_regs.h
+++ b/drivers/ntb/ntb_regs.h
@@ -143,11 +143,13 @@
 #define BWD_LTSSMSTATEJMP_FORCEDETECT  (1 << 2)
 #define BWD_IBIST_ERR_OFLOW    0x7FFF7FFF
 
 #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)
+#define NTB_CNTL_CFG_LOCK              (1 << 0)
+#define NTB_CNTL_LINK_DISABLE          (1 << 1)
+#define NTB_CNTL_S2P_BAR23_SNOOP       (1 << 2)
+#define NTB_CNTL_P2S_BAR23_SNOOP       (1 << 4)
+#define NTB_CNTL_S2P_BAR45_SNOOP       (1 << 6)
+#define NTB_CNTL_P2S_BAR45_SNOOP       (1 << 8)
+#define BWD_CNTL_LINK_DOWN             (1 << 16)

 
 #define NTB_PPD_OFFSET         0x00D4
 #define SNB_PPD_CONN_TYPE      0x0003
 
 #define NTB_PPD_OFFSET         0x00D4
 #define SNB_PPD_CONN_TYPE      0x0003