Re: [PATCH net] net: stmmac: dma channel control register need to be init first

Re: [PATCH net] net: stmmac: dma channel control register need to be init first

[David Miller]

From: Weifeng Voon <weifeng.voon@intel.com>
Date: Tue, 21 May 2019 13:38:38 +0800

> stmmac_init_chan() needs to be called before stmmac_init_rx_chan() and
> stmmac_init_tx_chan(). This is because if PBLx8 is to be used,
> "DMA_CH(#i)_Control.PBLx8" needs to be set before programming
> "DMA_CH(#i)_TX_Control.TxPBL" and "DMA_CH(#i)_RX_Control.RxPBL".
> 
> Fixes: 47f2a9ce527a ("net: stmmac: dma channel init prepared for multiple queues")
> Reviewed-by: Zhang, Baoli <baoli.zhang@intel.com>
> Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
> Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>

Applied and queued up for -stable.

Thanks.

[PATCH net] net: stmmac: dma channel control register need to be init first

[Weifeng Voon]

stmmac_init_chan() needs to be called before stmmac_init_rx_chan() and
stmmac_init_tx_chan(). This is because if PBLx8 is to be used,
"DMA_CH(#i)_Control.PBLx8" needs to be set before programming
"DMA_CH(#i)_TX_Control.TxPBL" and "DMA_CH(#i)_RX_Control.RxPBL".

Fixes: 47f2a9ce527a ("net: stmmac: dma channel init prepared for multiple queues")
Reviewed-by: Zhang, Baoli <baoli.zhang@intel.com>
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Signed-off-by: Weifeng Voon <weifeng.voon@intel.com>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 5678b869cbff..2a1052704885 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2208,6 +2208,10 @@ static int stmmac_init_dma_engine(struct stmmac_priv *priv)
 	if (priv->plat->axi)
 		stmmac_axi(priv, priv->ioaddr, priv->plat->axi);
 
+	/* DMA CSR Channel configuration */
+	for (chan = 0; chan < dma_csr_ch; chan++)
+		stmmac_init_chan(priv, priv->ioaddr, priv->plat->dma_cfg, chan);
+
 	/* DMA RX Channel Configuration */
 	for (chan = 0; chan < rx_channels_count; chan++) {
 		rx_q = &priv->rx_queue[chan];
@@ -2233,10 +2237,6 @@ static int stmmac_init_dma_engine(struct stmmac_priv *priv)
 				       tx_q->tx_tail_addr, chan);
 	}
 
-	/* DMA CSR Channel configuration */
-	for (chan = 0; chan < dma_csr_ch; chan++)
-		stmmac_init_chan(priv, priv->ioaddr, priv->plat->dma_cfg, chan);
-
 	return ret;
 }
 
-- 
1.9.1