openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

net: stmmac: Enable OSP for GMAC4 

This enables OSP (Operate on Second Packet) for GMAC4. The feature
allows DMA to fetch second descriptor while its still processing the
first one.

Running iperf, the performance gain is +/- 38%.

Signed-off-by: Jose Abreu <joabreu@synopsys.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Joao Pinto <jpinto@synopsys.com>
Cc: Vitor Soares <soares@synopsys.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jose Abreu 2018-05-18 14:55:58 +01:00 committed by David S. Miller
parent 538e2de104
commit 67e1c4068d
1 changed files with 4 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c
View File

@ -94,6 +94,10 @@ static void dwmac4_dma_init_tx_chan(void __iomem *ioaddr,
value = readl(ioaddr + DMA_CHAN_TX_CONTROL(chan));
value = value | (txpbl << DMA_BUS_MODE_PBL_SHIFT);
/* Enable OSP to get best performance */
value |= DMA_CONTROL_OSP;
writel(value, ioaddr + DMA_CHAN_TX_CONTROL(chan));
writel(dma_tx_phy, ioaddr + DMA_CHAN_TX_BASE_ADDR(chan));