From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Nicholas Piggin <npiggin@gmail.com>, linuxppc-dev@lists.ozlabs.org
Subject: Re: [PATCH 6/6] drivers/tty/hvc: remove unexplained "just in case" spin delay
Date: Mon, 09 Apr 2018 16:03:40 +1000 [thread overview]
Message-ID: <1523253820.11062.11.camel@kernel.crashing.org> (raw)
In-Reply-To: <20180409054056.27292-7-npiggin@gmail.com>
On Mon, 2018-04-09 at 15:40 +1000, Nicholas Piggin wrote:
> This delay was in the very first OPAL console commit 6.5 years ago.
> The firmware console has hardened sufficiently to remove it.
>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
> ---
> drivers/tty/hvc/hvc_opal.c | 8 +-------
> 1 file changed, 1 insertion(+), 7 deletions(-)
>
> diff --git a/drivers/tty/hvc/hvc_opal.c b/drivers/tty/hvc/hvc_opal.c
> index e151cfacf2a7..436b98258e60 100644
> --- a/drivers/tty/hvc/hvc_opal.c
> +++ b/drivers/tty/hvc/hvc_opal.c
> @@ -307,14 +307,8 @@ static int udbg_opal_getc(void)
> int ch;
> for (;;) {
> ch = udbg_opal_getc_poll();
> - if (ch == -1) {
> - /* This shouldn't be needed...but... */
> - volatile unsigned long delay;
> - for (delay=0; delay < 2000000; delay++)
> - ;
> - } else {
> + if (ch != -1)
> return ch;
> - }
> }
> }
>
prev parent reply other threads:[~2018-04-09 6:03 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-09 5:40 [PATCH 0/6] improve OPAL cosole flushing and locking Nicholas Piggin
2018-04-09 5:40 ` [PATCH 1/6] powerpc/powernv: opal-kmsg use flush fallback from console code Nicholas Piggin
2018-04-10 5:01 ` Russell Currey
2018-04-09 5:40 ` [PATCH 2/6] powerpc/powernv: Implement and use opal_flush_console Nicholas Piggin
2018-04-10 5:02 ` Russell Currey
2018-04-09 5:40 ` [PATCH 3/6] powerpc/powernv: Remove OPALv1 support from opal console driver Nicholas Piggin
2018-04-09 5:40 ` [PATCH 4/6] powerpc/powernv: move opal console flushing to udbg Nicholas Piggin
2018-04-09 5:40 ` [PATCH 5/6] powerpc/powernv: implement opal_put_chars_nonatomic Nicholas Piggin
2018-04-09 5:57 ` Benjamin Herrenschmidt
2018-04-09 6:23 ` Nicholas Piggin
2018-04-09 8:24 ` Benjamin Herrenschmidt
2018-04-09 9:02 ` Nicholas Piggin
2018-04-09 5:40 ` [PATCH 6/6] drivers/tty/hvc: remove unexplained "just in case" spin delay Nicholas Piggin
2018-04-09 6:03 ` Benjamin Herrenschmidt [this message]
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