[PATCH v2 net-next 4/7] net: stmmac: xgmac: Remove uneeded computation for RFA/RFD

From: Jose Abreu
Date: Thu Nov 14 2019 - 06:43:06 EST


RFA and RFD should not be dependent on FIFO size. In fact, the more FIFO
space we have, the later we can activate Flow Control. Let's use
hard-coded values for RFA and RFD for all FIFO sizes with the exception
of 4k, which is a special case.

Signed-off-by: Jose Abreu <Jose.Abreu@xxxxxxxxxxxx>

---
Cc: Giuseppe Cavallaro <peppe.cavallaro@xxxxxx>
Cc: Alexandre Torgue <alexandre.torgue@xxxxxx>
Cc: Jose Abreu <joabreu@xxxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Maxime Coquelin <mcoquelin.stm32@xxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: linux-stm32@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
index f148cb2061d8..22a7f0cc1b90 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -183,19 +183,9 @@ static void dwxgmac2_dma_rx_mode(void __iomem *ioaddr, int mode,
rfa = 0x01; /* Full-1.5K */
break;

- case 8192:
- rfd = 0x06; /* Full-4K */
- rfa = 0x0a; /* Full-6K */
- break;
-
- case 16384:
- rfd = 0x06; /* Full-4K */
- rfa = 0x12; /* Full-10K */
- break;
-
default:
- rfd = 0x06; /* Full-4K */
- rfa = 0x1e; /* Full-16K */
+ rfd = 0x07; /* Full-4.5K */
+ rfa = 0x04; /* Full-3K */
break;
}

--
2.7.4