[PATCH v1 3/7] fpga: dfl: Allow for ports with no local bar space.

Tianfei zhang
2022-02-14T11:39:46Z

From: Matthew Gerlach <matthew.gerlach@linux.intel.com>

From a fpga partial reconfiguration standpoint, a port
may not be connected any local BAR space. The port could
be connected to a different PCIe Physical Function (PF) or
Virtual Function (VF), in which case another driver instance
would manage the endpoint.

Signed-off-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
Signed-off-by: Tianfei Zhang <tianfei.zhang@intel.com>
---
drivers/fpga/dfl-pci.c | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/drivers/fpga/dfl-pci.c b/drivers/fpga/dfl-pci.c
index 4d68719e608f..8abd9b408403 100644
--- a/drivers/fpga/dfl-pci.c
+++ b/drivers/fpga/dfl-pci.c
@@ -243,6 +243,7 @@ static int find_dfls_by_default(struct pci_dev *pcidev,
v = readq(base + FME_HDR_CAP);
port_num = FIELD_GET(FME_CAP_NUM_PORTS, v);

+ dev_info(&pcidev->dev, "port_num = %d\n", port_num);
WARN_ON(port_num > MAX_DFL_FPGA_PORT_NUM);

for (i = 0; i < port_num; i++) {
@@ -258,6 +259,13 @@ static int find_dfls_by_default(struct pci_dev *pcidev,
*/
bar = FIELD_GET(FME_PORT_OFST_BAR_ID, v);
offset = FIELD_GET(FME_PORT_OFST_DFH_OFST, v);
+ if (bar >= PCI_STD_NUM_BARS) {
+ dev_info(&pcidev->dev, "skipping port without local BAR space %d\n",
+ bar);
+ continue;
+ } else {
+ dev_info(&pcidev->dev, "BAR %d offset %u\n", bar, offset);
+ }
start = pci_resource_start(pcidev, bar) + offset;
len = pci_resource_len(pcidev, bar) - offset;

--
2.17.1