From 49e4a2293035b420e807e739999d59c8ec1488e9 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Thu, 12 Nov 2015 22:03:40 +0100 Subject: stmmac: avoid ipq806x constant overflow warning Building dwmac-ipq806x on a 64-bit architecture produces a harmless warning from gcc: stmmac/dwmac-ipq806x.c: In function 'ipq806x_gmac_probe': include/linux/bitops.h:6:19: warning: overflow in implicit constant conversion [-Woverflow] val = QSGMII_PHY_CDR_EN | stmmac/dwmac-ipq806x.c:333:8: note: in expansion of macro 'QSGMII_PHY_CDR_EN' #define QSGMII_PHY_CDR_EN BIT(0) #define BIT(nr) (1UL << (nr)) This is a result of the type conversion rules in C, when we take the logical OR of multiple different types. In particular, we have and unsigned long QSGMII_PHY_CDR_EN == BIT(0) == (1ul << 0) == 0x0000000000000001ul and a signed int 0xC << QSGMII_PHY_TX_DRV_AMP_OFFSET == 0xc0000000 which together gives a signed long value 0xffffffffc0000001l and when this is passed into a function that takes an unsigned int type, gcc warns about the signed overflow and the loss of the upper 32-bits that are all ones. This patch adds 'ul' type modifiers to the literal numbers passed in here, so now the expression remains an 'unsigned long' with the upper bits all zero, and that avoids the signed overflow and the warning. Signed-off-by: Arnd Bergmann Fixes: b1c17215d718 ("stmmac: add ipq806x glue layer") Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c') diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c index 9d89bdbf029f..82de68b1a452 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c @@ -337,11 +337,11 @@ static int ipq806x_gmac_probe(struct platform_device *pdev) QSGMII_PHY_RX_SIGNAL_DETECT_EN | QSGMII_PHY_TX_DRIVER_EN | QSGMII_PHY_QSGMII_EN | - 0x4 << QSGMII_PHY_PHASE_LOOP_GAIN_OFFSET | - 0x3 << QSGMII_PHY_RX_DC_BIAS_OFFSET | - 0x1 << QSGMII_PHY_RX_INPUT_EQU_OFFSET | - 0x2 << QSGMII_PHY_CDR_PI_SLEW_OFFSET | - 0xC << QSGMII_PHY_TX_DRV_AMP_OFFSET); + 0x4ul << QSGMII_PHY_PHASE_LOOP_GAIN_OFFSET | + 0x3ul << QSGMII_PHY_RX_DC_BIAS_OFFSET | + 0x1ul << QSGMII_PHY_RX_INPUT_EQU_OFFSET | + 0x2ul << QSGMII_PHY_CDR_PI_SLEW_OFFSET | + 0xCul << QSGMII_PHY_TX_DRV_AMP_OFFSET); } plat_dat->has_gmac = true; -- cgit v1.2.3