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 <arnd@arndb.de> Fixes: b1c17215 ("stmmac: add ipq806x glue layer") Signed-off-by: David S. Miller <davem@davemloft.net>
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