In drivers/ntb/hw/epf/ntb_hw_epf.c ntb_epf_peer_db_set() { ... db_offset = readl(ndev->ctrl_reg + NTB_EPF_DB_OFFSET(interrupt_num)); writel(db_data, ndev->db_reg + (db_entry_size * interrupt_num) + db_offset); ... } The door register offset's formular is offset = db_entry_size * interrupt_num + db_offset[interrupt_number] Previous db_entry_size is 4, all db_offset is 0. irq | offset -------------- 0 0 1 4 2 8 ... Change to db_entry_size is 0 and db_offset is 0, 4, 8, ... So we can get the same map value between irq and offset. This will be convenience for hardware doorbell register memory map. Signed-off-by: Frank Li <Frank.Li@xxxxxxx> --- drivers/pci/endpoint/functions/pci-epf-vntb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c b/drivers/pci/endpoint/functions/pci-epf-vntb.c index 04698e7995a5..0d744975f815 100644 --- a/drivers/pci/endpoint/functions/pci-epf-vntb.c +++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c @@ -461,11 +461,11 @@ static int epf_ntb_config_spad_bar_alloc(struct epf_ntb *ntb) ctrl->num_mws = ntb->num_mws; ntb->spad_size = spad_size; - ctrl->db_entry_size = sizeof(u32); + ctrl->db_entry_size = 0; for (i = 0; i < ntb->db_count; i++) { ntb->reg->db_data[i] = 1 + i; - ntb->reg->db_offset[i] = 0; + ntb->reg->db_offset[i] = sizeof(u32) * i; } return 0; -- 2.34.1