[PATCH v13 1/2] PCI: endpoint: pci-epf-vntb: change doorbell register offset calc mathod

[Frank Li]

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 at nxp.com>
---
 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