[PATCH 4.17 57/63] net: systemport: Fix CRC forwarding check for SYSTEMPORT Lite

[Greg Kroah-Hartman]

4.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Florian Fainelli <f.fainelli@xxxxxxxxx>

[ Upstream commit 9e3bff923913729d76d87f0015848ee7b8ff7083 ]

SYSTEMPORT Lite reversed the logic compared to SYSTEMPORT, the
GIB_FCS_STRIP bit is set when the Ethernet FCS is stripped, and that bit
is not set by default. Fix the logic such that we properly check whether
that bit is set or not and we don't forward an extra 4 bytes to the
network stack.

Fixes: 44a4524c54af ("net: systemport: Add support for SYSTEMPORT Lite")
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/broadcom/bcmsysport.c |    4 ++--
 drivers/net/ethernet/broadcom/bcmsysport.h |    3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -1946,8 +1946,8 @@ static int bcm_sysport_open(struct net_d
 	if (!priv->is_lite)
 		priv->crc_fwd = !!(umac_readl(priv, UMAC_CMD) & CMD_CRC_FWD);
 	else
-		priv->crc_fwd = !!(gib_readl(priv, GIB_CONTROL) &
-				   GIB_FCS_STRIP);
+		priv->crc_fwd = !((gib_readl(priv, GIB_CONTROL) &
+				  GIB_FCS_STRIP) >> GIB_FCS_STRIP_SHIFT);
 
 	phydev = of_phy_connect(dev, priv->phy_dn, bcm_sysport_adj_link,
 				0, priv->phy_interface);
--- a/drivers/net/ethernet/broadcom/bcmsysport.h
+++ b/drivers/net/ethernet/broadcom/bcmsysport.h
@@ -278,7 +278,8 @@ struct bcm_rsb {
 #define  GIB_GTX_CLK_EXT_CLK		(0 << GIB_GTX_CLK_SEL_SHIFT)
 #define  GIB_GTX_CLK_125MHZ		(1 << GIB_GTX_CLK_SEL_SHIFT)
 #define  GIB_GTX_CLK_250MHZ		(2 << GIB_GTX_CLK_SEL_SHIFT)
-#define  GIB_FCS_STRIP			(1 << 6)
+#define  GIB_FCS_STRIP_SHIFT		6
+#define  GIB_FCS_STRIP			(1 << GIB_FCS_STRIP_SHIFT)
 #define  GIB_LCL_LOOP_EN		(1 << 7)
 #define  GIB_LCL_LOOP_TXEN		(1 << 8)
 #define  GIB_RMT_LOOP_EN		(1 << 9)