rdma/cxgb4: Fixes cxgb4 probe failure in VM when PF is exposed through PCI Passthrough

Change logic which determines our Physical Function at PCI Probe time.
Now we read the PL_WHOAMI register and get the Physical Function.

Pass Physical Function to Upper Layer Drivers in lld_info structure in the
new field "pf" added to lld_info.  This is useful for the cases where the
PF, say PF4, is attached to a Virtual Machine via some form of "PCI
Pass Through" technology and the PCI Function shows up as PF0 in the VM.

Based on original work by Casey Leedom <leedom@chelsio.com>

Signed-off-by: Casey Leedom <leedom@chelsio.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
index 5e153f6..d62a0f9 100644 (file)
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -465,7 +465,8 @@ static void send_flowc(struct c4iw_ep *ep, struct sk_buff *skb)
                                          16)) | FW_WR_FLOWID(ep->hwtid));
 
        flowc->mnemval[0].mnemonic = FW_FLOWC_MNEM_PFNVFN;
-       flowc->mnemval[0].val = cpu_to_be32(PCI_FUNC(ep->com.dev->rdev.lldi.pdev->devfn) << 8);
+       flowc->mnemval[0].val = cpu_to_be32(FW_PFVF_CMD_PFN
+                                           (ep->com.dev->rdev.lldi.pf));
        flowc->mnemval[1].mnemonic = FW_FLOWC_MNEM_CH;
        flowc->mnemval[1].val = cpu_to_be32(ep->tx_chan);
        flowc->mnemval[2].mnemonic = FW_FLOWC_MNEM_PORT;

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index b7154dc..e8e77b8 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -4053,6 +4053,7 @@ static void uld_attach(struct adapter *adap, unsigned int uld)
        unsigned short i;
 
        lli.pdev = adap->pdev;
+       lli.pf = adap->fn;
        lli.l2t = adap->l2t;
        lli.tids = &adap->tids;
        lli.ports = adap->port;
@@ -6294,13 +6295,6 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
                return err;
        }
 
-       /* We control everything through one PF */
-       func = PCI_FUNC(pdev->devfn);
-       if (func != ent->driver_data) {
-               pci_save_state(pdev);        /* to restore SR-IOV later */
-               goto sriov;
-       }
-
        err = pci_enable_device(pdev);
        if (err) {
                dev_err(&pdev->dev, "cannot enable PCI device\n");
@@ -6344,6 +6338,15 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
                goto out_free_adapter;
        }
 
+       /* We control everything through one PF */
+       func = SOURCEPF_GET(readl(adapter->regs + PL_WHOAMI));
+       if ((pdev->device == 0xa000 && func != 0) ||
+           func != ent->driver_data) {
+               pci_save_state(pdev);        /* to restore SR-IOV later */
+               err = 0;
+               goto out_unmap_bar0;
+       }
+
        adapter->pdev = pdev;
        adapter->pdev_dev = &pdev->dev;
        adapter->mbox = func;
@@ -6507,7 +6510,6 @@ static int init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
        if (is_offload(adapter))
                attach_ulds(adapter);
 
-sriov:
 #ifdef CONFIG_PCI_IOV
        if (func < ARRAY_SIZE(num_vf) && num_vf[func] > 0)
                if (pci_enable_sriov(pdev, num_vf[func]) == 0)

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.h b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.h
index d719dec..8f60851 100644 (file)
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.h
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.h
@@ -253,6 +253,7 @@ struct cxgb4_lld_info {
        int dbfifo_int_thresh;               /* doorbell fifo int threshold */
        unsigned int sge_pktshift;           /* Padding between CPL and */
                                             /* packet data */
+       unsigned int pf;                     /* Physical Function we're using */
        bool enable_fw_ofld_conn;            /* Enable connection through fw */
                                             /* WR */
        bool ulptx_memwrite_dsgl;            /* use of T5 DSGL allowed */