From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH 3/5] net: add Hisilicon Network Subsystem MDIO support Date: Fri, 14 Aug 2015 22:57:28 +0200 Message-ID: <2142879.tTtWetb0nc@wuerfel> References: <1439548222-231611-1-git-send-email-liguozhu@hisilicon.com> <1439548222-231611-4-git-send-email-liguozhu@hisilicon.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: <1439548222-231611-4-git-send-email-liguozhu@hisilicon.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-arm-kernel@lists.infradead.org Cc: Kenneth Lee , robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, catalin.marinas@arm.com, will.deacon@arm.com, Yisen.Zhuang@huawei.com, davem@davemloft.net, paul.gortmaker@windriver.com, dingtianhong@huawei.com, zhangfei.gao@linaro.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linuxarm@huawei.com, salil.mehta@huawei.com, huangdaode@hisilicon.com, Kenneth Lee List-Id: devicetree@vger.kernel.org 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