[PATCH 2/9] NTB: Fix NTB-RP Link Up

From: Jon Mason
Date: Wed Nov 20 2013 - 19:22:12 EST


The Xeon NTB-RP setup, the transparent side does not get a link up/down
interrupt. Since the presence of a NTB device on the transparent side
means that we have a NTB link up, we can work around the lack of an
interrupt by simply calling the link up function to notify the upper
layers.

Signed-off-by: Jon Mason <jon.mason@xxxxxxxxx>
---
drivers/ntb/ntb_hw.c | 36 ++++++++++++++++++++++++++++--------
1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c
index 6c9d733..a9b065f 100644
--- a/drivers/ntb/ntb_hw.c
+++ b/drivers/ntb/ntb_hw.c
@@ -1296,6 +1296,32 @@ static void ntb_free_debugfs(struct ntb_device *ndev)
}
}

+static void ntb_hw_link_up(struct ntb_device *ndev)
+{
+ if (ndev->conn_type == NTB_CONN_TRANSPARENT)
+ ntb_link_event(ndev, NTB_LINK_UP);
+ else
+ /* Let's bring the NTB link up */
+ writel(NTB_CNTL_BAR23_SNOOP | NTB_CNTL_BAR45_SNOOP,
+ ndev->reg_ofs.lnk_cntl);
+}
+
+static void ntb_hw_link_down(struct ntb_device *ndev)
+{
+ u32 ntb_cntl;
+
+ if (ndev->conn_type == NTB_CONN_TRANSPARENT) {
+ ntb_link_event(ndev, NTB_LINK_DOWN);
+ return;
+ }
+
+ /* 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;
+ writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+}
+
static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct ntb_device *ndev;
@@ -1384,9 +1410,7 @@ static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
if (rc)
goto err6;

- /* Let's bring the NTB link up */
- writel(NTB_CNTL_BAR23_SNOOP | NTB_CNTL_BAR45_SNOOP,
- ndev->reg_ofs.lnk_cntl);
+ ntb_hw_link_up(ndev);

return 0;

@@ -1416,12 +1440,8 @@ static void ntb_pci_remove(struct pci_dev *pdev)
{
struct ntb_device *ndev = pci_get_drvdata(pdev);
int i;
- u32 ntb_cntl;

- /* Bring NTB link down */
- ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
- ntb_cntl |= NTB_CNTL_LINK_DISABLE;
- writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+ ntb_hw_link_down(ndev);

ntb_transport_free(ndev->ntb_transport);

--
1.7.9.5

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