linux-riscv.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
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

_______________________________________________
linux-riscv mailing list
linux-riscv@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-riscv

      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]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190530063232.GA17102@andestech.com \
    --to=nickhu@andestech.com \
    --cc=green.hu@gmail.com \
    --cc=greentime@andestech.com \
    --cc=hch@infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=palmer@sifive.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).