All of lore.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Nick Hu <nickhu@andestech.com>
Cc: linux-riscv@lists.infradead.org, palmer@sifive.com,
	linux-kernel@vger.kernel.org, green.hu@gmail.com,
	greentime@andestech.com
Subject: Re: [PATCH] riscv: Fix udelay in RV32.
Date: Wed, 29 May 2019 22:52:58 -0700	[thread overview]
Message-ID: <20190530055258.GA7170@infradead.org> (raw)
In-Reply-To: <381ee6950c84b868ca6a3c676eb981a1980889a3.1559035050.git.nickhu@andestech.com>

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.

> 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.

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

WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@infradead.org>
To: Nick Hu <nickhu@andestech.com>
Cc: greentime@andestech.com, palmer@sifive.com,
	linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
	green.hu@gmail.com
Subject: Re: [PATCH] riscv: Fix udelay in RV32.
Date: Wed, 29 May 2019 22:52:58 -0700	[thread overview]
Message-ID: <20190530055258.GA7170@infradead.org> (raw)
In-Reply-To: <381ee6950c84b868ca6a3c676eb981a1980889a3.1559035050.git.nickhu@andestech.com>

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.

> 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.

  parent reply	other threads:[~2019-05-30  5:53 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-28  9:26 [PATCH] riscv: Fix udelay in RV32 Nick Hu
2019-05-28  9:26 ` Nick Hu
2019-05-30  4:09 ` Palmer Dabbelt
2019-05-30  4:09   ` Palmer Dabbelt
2019-05-30  5:52 ` Christoph Hellwig [this message]
2019-05-30  5:52   ` Christoph Hellwig
2019-05-30  6:32   ` Nick Hu
2019-05-30  6:32     ` Nick Hu

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=20190530055258.GA7170@infradead.org \
    --to=hch@infradead.org \
    --cc=green.hu@gmail.com \
    --cc=greentime@andestech.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-riscv@lists.infradead.org \
    --cc=nickhu@andestech.com \
    --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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.