From: Andrew Lunn <andrew@lunn.ch>
To: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
Cc: Felix Fietkau <nbd@nbd.name>, John Crispin <john@phrozen.org>,
Sean Wang <sean.wang@mediatek.com>,
Mark Lee <Mark-MC.Lee@mediatek.com>,
"David S. Miller" <davem@davemloft.net>,
Jakub Kicinski <kuba@kernel.org>,
Matthias Brugger <matthias.bgg@gmail.com>,
Pablo Neira Ayuso <pablo@netfilter.org>,
netdev@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next] net: ethernet: mediatek: ppe: fix busy wait loop
Date: Fri, 16 Apr 2021 01:10:20 +0200 [thread overview]
Message-ID: <YHjH3DxteZrID2hW@lunn.ch> (raw)
In-Reply-To: <20210415230234.14895-1-ilya.lipnitskiy@gmail.com>
On Thu, Apr 15, 2021 at 04:02:34PM -0700, Ilya Lipnitskiy wrote:
> The intention is for the loop to timeout if the body does not succeed.
> The current logic calls time_is_before_jiffies(timeout) which is false
> until after the timeout, so the loop body never executes.
>
> time_is_after_jiffies(timeout) will return true until timeout is less
> than jiffies, which is the intended behavior here.
>
> Fixes: ba37b7caf1ed ("net: ethernet: mtk_eth_soc: add support for initializing the PPE")
> Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
> Cc: Felix Fietkau <nbd@nbd.name>
> ---
> drivers/net/ethernet/mediatek/mtk_ppe.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mediatek/mtk_ppe.c b/drivers/net/ethernet/mediatek/mtk_ppe.c
> index 71e1ccea6e72..af3c266297aa 100644
> --- a/drivers/net/ethernet/mediatek/mtk_ppe.c
> +++ b/drivers/net/ethernet/mediatek/mtk_ppe.c
> @@ -46,7 +46,7 @@ static int mtk_ppe_wait_busy(struct mtk_ppe *ppe)
> {
> unsigned long timeout = jiffies + HZ;
>
> - while (time_is_before_jiffies(timeout)) {
> + while (time_is_after_jiffies(timeout)) {
> if (!(ppe_r32(ppe, MTK_PPE_GLO_CFG) & MTK_PPE_GLO_CFG_BUSY))
> return 0;
Maybe see is iopoll.h can be used.
Andrew
>
> --
> 2.31.1
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-04-15 23:10 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-15 23:02 [PATCH net-next] net: ethernet: mediatek: ppe: fix busy wait loop Ilya Lipnitskiy
2021-04-15 23:10 ` Andrew Lunn [this message]
2021-04-16 0:11 ` [PATCH net-next,v2] " Ilya Lipnitskiy
2021-04-16 0:27 ` Andrew Lunn
2021-04-16 0:37 ` [PATCH net-next,v3] " Ilya Lipnitskiy
2021-04-16 22:30 ` patchwork-bot+netdevbpf
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=YHjH3DxteZrID2hW@lunn.ch \
--to=andrew@lunn.ch \
--cc=Mark-MC.Lee@mediatek.com \
--cc=davem@davemloft.net \
--cc=ilya.lipnitskiy@gmail.com \
--cc=john@phrozen.org \
--cc=kuba@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mediatek@lists.infradead.org \
--cc=matthias.bgg@gmail.com \
--cc=nbd@nbd.name \
--cc=netdev@vger.kernel.org \
--cc=pablo@netfilter.org \
--cc=sean.wang@mediatek.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).