On Friday 14 August 2015 18:30:20 Kenneth Lee wrote: > +#define MDIO_BASE_ADDR 0x403C0000 Does not belong in here (and is not used) > +#define MDIO_COMMAND_REG 0x0 > +#define MDIO_ADDR_REG 0x4 > +#define MDIO_WDATA_REG 0x8 > +#define MDIO_RDATA_REG 0xc > +#define MDIO_STA_REG 0x10 These look suspiciously similar to definitions from drivers/net/ethernet/hisilicon/hip04_mdio.c. Could the hardware be related? If so, please try to share the common parts. > +static inline void mdio_write_reg(void *base, u32 reg, u32 value) > +{ > + u8 __iomem *reg_addr = ACCESS_ONCE(base); > + > + writel(value, reg_addr + reg); > +} > + > +#define MDIO_WRITE_REG(a, reg, value) \ > + mdio_write_reg((a)->vbase, (reg), (value)) > Something seems wrong here: why do you have an ACCESS_ONCE() on a local variable? Doesn't this just make the code less efficient without providing lockless access to shared variables? The types are inconsistent here, you should get a warning from running this through 'make C=1' because of the missing __iomem annotation of the pointer. Also, why both a macro and an inline function? Just use an inline function. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html