From: Nick Hu <nickhu@andestech.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: "linux-riscv@lists.infradead.org"
<linux-riscv@lists.infradead.org>,
"palmer@sifive.com" <palmer@sifive.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"Greentime Ying-Han Hu(胡英漢)" <greentime@andestech.com>,
"green.hu@gmail.com" <green.hu@gmail.com>
Subject: Re: [PATCH] riscv: Fix udelay in RV32.
Date: Thu, 30 May 2019 14:32:32 +0800 [thread overview]
Message-ID: <20190530063232.GA17102@andestech.com> (raw)
In-Reply-To: <20190530055258.GA7170@infradead.org>
On Thu, May 30, 2019 at 01:52:58PM +0800, Christoph Hellwig wrote:
> On Tue, May 28, 2019 at 05:26:49PM +0800, Nick Hu wrote:
> > In RV32, udelay would delay the wrong cycle.
> > When it shifts right "UDELAY_SHITFT" bits, it
> > either delays 0 cycle or 1 cycle. It only works
> > correctly in RV64. Because the 'ucycles' always
> > needs to be 64 bits variable.
>
> Please use up all your ~72 chars per line in the commit log.
>
OK, Thanks!
> > diff --git a/arch/riscv/lib/delay.c b/arch/riscv/lib/delay.c
> > index dce8ae24c6d3..da847f49fb74 100644
> > --- a/arch/riscv/lib/delay.c
> > +++ b/arch/riscv/lib/delay.c
> > @@ -88,7 +88,7 @@ EXPORT_SYMBOL(__delay);
> >
> > void udelay(unsigned long usecs)
> > {
> > - unsigned long ucycles = usecs * lpj_fine * UDELAY_MULT;
> > + unsigned long long ucycles = (unsigned long long)usecs * lpj_fine * UDELAY_MULT;
>
> And this creates a way too long line. Pleaase use u64 instead of
> unsigned long long to clarify the intention while also fixing the long
> lines.
>
Sure, I will fix it and send another patch. Thanks.
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv
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prev parent reply other threads:[~2019-05-30 6:33 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-28 9:26 [PATCH] riscv: Fix udelay in RV32 Nick Hu
2019-05-30 4:09 ` Palmer Dabbelt
2019-05-30 5:52 ` Christoph Hellwig
2019-05-30 6:32 ` Nick Hu [this message]
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