NTB: define a new function to get link status
authorArindam Nath <arindam.nath@amd.com>
Wed, 5 Feb 2020 15:54:21 +0000 (21:24 +0530)
committerJon Mason <jdmason@kudzu.us>
Fri, 13 Mar 2020 14:04:19 +0000 (10:04 -0400)
Since getting the status of link is a logically separate
operation, we simply create a new function which will
store the link status to be used later.

Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
drivers/ntb/hw/amd/ntb_hw_amd.c

index 111f33f..f50537e 100644 (file)
@@ -195,6 +195,54 @@ static int amd_ntb_mw_set_trans(struct ntb_dev *ntb, int pidx, int idx,
        return 0;
 }
 
+static int amd_ntb_get_link_status(struct amd_ntb_dev *ndev)
+{
+       struct pci_dev *pdev = NULL;
+       struct pci_dev *pci_swds = NULL;
+       struct pci_dev *pci_swus = NULL;
+       u32 stat;
+       int rc;
+
+       if (ndev->ntb.topo == NTB_TOPO_SEC) {
+               /* Locate the pointer to Downstream Switch for this device */
+               pci_swds = pci_upstream_bridge(ndev->ntb.pdev);
+               if (pci_swds) {
+                       /*
+                        * Locate the pointer to Upstream Switch for
+                        * the Downstream Switch.
+                        */
+                       pci_swus = pci_upstream_bridge(pci_swds);
+                       if (pci_swus) {
+                               rc = pcie_capability_read_dword(pci_swus,
+                                                               PCI_EXP_LNKCTL,
+                                                               &stat);
+                               if (rc)
+                                       return 0;
+                       } else {
+                               return 0;
+                       }
+               } else {
+                       return 0;
+               }
+       } else if (ndev->ntb.topo == NTB_TOPO_PRI) {
+               /*
+                * For NTB primary, we simply read the Link Status and control
+                * register of the NTB device itself.
+                */
+               pdev = ndev->ntb.pdev;
+               rc = pcie_capability_read_dword(pdev, PCI_EXP_LNKCTL, &stat);
+               if (rc)
+                       return 0;
+       } else {
+               /* Catch all for everything else */
+               return 0;
+       }
+
+       ndev->lnk_sta = stat;
+
+       return 1;
+}
+
 static int amd_link_is_up(struct amd_ntb_dev *ndev)
 {
        if (!ndev->peer_sta)
@@ -845,11 +893,7 @@ static inline void ndev_init_struct(struct amd_ntb_dev *ndev,
 static int amd_poll_link(struct amd_ntb_dev *ndev)
 {
        void __iomem *mmio = ndev->peer_mmio;
-       struct pci_dev *pdev = NULL;
-       struct pci_dev *pci_swds = NULL;
-       struct pci_dev *pci_swus = NULL;
-       u32 reg, stat;
-       int rc;
+       u32 reg;
 
        reg = readl(mmio + AMD_SIDEINFO_OFFSET);
        reg &= NTB_LIN_STA_ACTIVE_BIT;
@@ -861,44 +905,7 @@ static int amd_poll_link(struct amd_ntb_dev *ndev)
 
        ndev->cntl_sta = reg;
 
-       if (ndev->ntb.topo == NTB_TOPO_SEC) {
-               /* Locate the pointer to Downstream Switch for this device */
-               pci_swds = pci_upstream_bridge(ndev->ntb.pdev);
-               if (pci_swds) {
-                       /*
-                        * Locate the pointer to Upstream Switch for
-                        * the Downstream Switch.
-                        */
-                       pci_swus = pci_upstream_bridge(pci_swds);
-                       if (pci_swus) {
-                               rc = pcie_capability_read_dword(pci_swus,
-                                                               PCI_EXP_LNKCTL,
-                                                               &stat);
-                               if (rc)
-                                       return 0;
-                       } else {
-                               return 0;
-                       }
-               } else {
-                       return 0;
-               }
-       } else if (ndev->ntb.topo == NTB_TOPO_PRI) {
-               /*
-                * For NTB primary, we simply read the Link Status and control
-                * register of the NTB device itself.
-                */
-               pdev = ndev->ntb.pdev;
-               rc = pcie_capability_read_dword(pdev, PCI_EXP_LNKCTL, &stat);
-               if (rc)
-                       return 0;
-       } else {
-               /* Catch all for everything else */
-               return 0;
-       }
-
-       ndev->lnk_sta = stat;
-
-       return 1;
+       return amd_ntb_get_link_status(ndev);
 }
 
 static void amd_link_hb(struct work_struct *work)