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

Frank Li
2022-11-24T05:51:20Z

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@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