[PATCH net v3 5/9] net: stmmac: xgmac: Clear previous RX buffer size

[Jose Abreu <Jose.Abreu@synopsys.com>]

When switching between buffer sizes we need to clear the previous value.

Fixes: d6ddfacd95c7 ("net: stmmac: Add DMA related callbacks for XGMAC2")
Signed-off-by: Jose Abreu <Jose.Abreu@synopsys.com>

---
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Jose Abreu <joabreu@synopsys.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: netdev@vger.kernel.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h     | 2 ++
 drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
index 3b6e559aa0b9..ef8a07c68ca7 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
@@ -343,6 +343,8 @@
 #define XGMAC_DMA_CH_RX_CONTROL(x)	(0x00003108 + (0x80 * (x)))
 #define XGMAC_RxPBL			GENMASK(21, 16)
 #define XGMAC_RxPBL_SHIFT		16
+#define XGMAC_RBSZ			GENMASK(14, 1)
+#define XGMAC_RBSZ_SHIFT		1
 #define XGMAC_RXST			BIT(0)
 #define XGMAC_DMA_CH_TxDESC_HADDR(x)	(0x00003110 + (0x80 * (x)))
 #define XGMAC_DMA_CH_TxDESC_LADDR(x)	(0x00003114 + (0x80 * (x)))
diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
index 22a7f0cc1b90..f3f08ccc379b 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -482,7 +482,8 @@ static void dwxgmac2_set_bfsize(void __iomem *ioaddr, int bfsize, u32 chan)
 	u32 value;
 
 	value = readl(ioaddr + XGMAC_DMA_CH_RX_CONTROL(chan));
-	value |= bfsize << 1;
+	value &= ~XGMAC_RBSZ;
+	value |= bfsize << XGMAC_RBSZ_SHIFT;
 	writel(value, ioaddr + XGMAC_DMA_CH_RX_CONTROL(chan));
 }
 
-- 
2.7.4