[PATCH 5.4 113/165] net: stmmac: xgmac: Clear previous RX buffer size

From: Greg Kroah-Hartman
Date: Sat Jan 11 2020 - 05:30:52 EST


From: Jose Abreu <Jose.Abreu@xxxxxxxxxxxx>

[ Upstream commit 11d55fd9975f8e46a0e5e19c14899544e81e1e15 ]

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@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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 9d08a934fe4f..ff751ab3d765 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 f70ca5300b82..4af7271cea56 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
@@ -489,7 +489,8 @@ 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));
}

--
2.20.1