From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B7351C433EF for ; Fri, 10 Dec 2021 18:23:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239430AbhLJS0o (ORCPT ); Fri, 10 Dec 2021 13:26:44 -0500 Received: from sin.source.kernel.org ([145.40.73.55]:40184 "EHLO sin.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235682AbhLJS0o (ORCPT ); Fri, 10 Dec 2021 13:26:44 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id 60A19CE2C88; Fri, 10 Dec 2021 18:23:07 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BB134C00446; Fri, 10 Dec 2021 18:23:03 +0000 (UTC) Date: Fri, 10 Dec 2021 18:23:00 +0000 From: Catalin Marinas To: Sai Prakash Ranjan Cc: Will Deacon , Marc Zyngier , Arnd Bergmann , Steven Rostedt , gregkh , quic_psodagud@quicinc.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org Subject: Re: [PATCHv6 1/5] arm64: io: Use asm-generic high level MMIO accessors Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 10, 2021 at 06:16:43PM +0000, Catalin Marinas wrote: > On Tue, Dec 07, 2021 at 12:24:45PM +0530, Sai Prakash Ranjan wrote: > > Remove custom arm64 MMIO accessors read{b,w,l,q} and their relaxed > > versions in support to use asm-generic defined accessors. Also define > > one set of IO barriers (ar/bw version) used by asm-generic code to > > override the arm64 specific variants. > > > > Suggested-by: Arnd Bergmann > > Signed-off-by: Sai Prakash Ranjan > > --- > > arch/arm64/include/asm/io.h | 41 ++++++++----------------------------- > > 1 file changed, 8 insertions(+), 33 deletions(-) > > > > diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h > > index 7fd836bea7eb..1b436810d779 100644 > > --- a/arch/arm64/include/asm/io.h > > +++ b/arch/arm64/include/asm/io.h > > @@ -91,7 +91,7 @@ static inline u64 __raw_readq(const volatile void __iomem *addr) > > } > > > > /* IO barriers */ > > -#define __iormb(v) \ > > +#define __io_ar(v) \ > > ({ \ > > unsigned long tmp; \ > > \ > > @@ -108,39 +108,14 @@ static inline u64 __raw_readq(const volatile void __iomem *addr) > > : "memory"); \ > > }) > > > > -#define __io_par(v) __iormb(v) > > -#define __iowmb() dma_wmb() > > -#define __iomb() dma_mb() > > - > > -/* > > - * Relaxed I/O memory access primitives. These follow the Device memory > > - * ordering rules but do not guarantee any ordering relative to Normal memory > > - * accesses. > > - */ > > -#define readb_relaxed(c) ({ u8 __r = __raw_readb(c); __r; }) > > -#define readw_relaxed(c) ({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; }) > > -#define readl_relaxed(c) ({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; }) > > -#define readq_relaxed(c) ({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; }) > > +#define __io_bw() dma_wmb() > > +#define __io_br(v) > > +#define __io_aw(v) > > > > -#define writeb_relaxed(v,c) ((void)__raw_writeb((v),(c))) > > -#define writew_relaxed(v,c) ((void)__raw_writew((__force u16)cpu_to_le16(v),(c))) > > -#define writel_relaxed(v,c) ((void)__raw_writel((__force u32)cpu_to_le32(v),(c))) > > -#define writeq_relaxed(v,c) ((void)__raw_writeq((__force u64)cpu_to_le64(v),(c))) > > - > > -/* > > - * I/O memory access primitives. Reads are ordered relative to any > > - * following Normal memory access. Writes are ordered relative to any prior > > - * Normal memory access. > > - */ > > -#define readb(c) ({ u8 __v = readb_relaxed(c); __iormb(__v); __v; }) > > -#define readw(c) ({ u16 __v = readw_relaxed(c); __iormb(__v); __v; }) > > -#define readl(c) ({ u32 __v = readl_relaxed(c); __iormb(__v); __v; }) > > -#define readq(c) ({ u64 __v = readq_relaxed(c); __iormb(__v); __v; }) > > - > > -#define writeb(v,c) ({ __iowmb(); writeb_relaxed((v),(c)); }) > > -#define writew(v,c) ({ __iowmb(); writew_relaxed((v),(c)); }) > > -#define writel(v,c) ({ __iowmb(); writel_relaxed((v),(c)); }) > > -#define writeq(v,c) ({ __iowmb(); writeq_relaxed((v),(c)); }) > > +/* arm64-specific, don't use in portable drivers */ > > +#define __iormb(v) __io_ar(v) > > +#define __iowmb() __io_bw() > > +#define __iomb() dma_mb() > > More of a nitpick but I'd keep the __iormb()/__iowmb() as they currently > are and just define the generic __io_ar() etc. in terms of the former. Ah, I now noticed this was discussed in v5. Well, you can leave it as here and hopefully we get to remove the __io*mb() from various drivers. -- Catalin