From: Dongsheng Wang <dongsheng.wang@freescale.com>
To: <scottwood@freescale.com>
Cc: linuxppc-dev@lists.ozlabs.org,
Wang Dongsheng <dongsheng.wang@freescale.com>
Subject: [PATCH v2 1/2] powerpc/mpic_timer: fix the time is not accurate caused by GTCRR toggle bit
Date: Mon, 6 Jan 2014 13:23:30 +0800 [thread overview]
Message-ID: <1388985811-32495-1-git-send-email-dongsheng.wang@freescale.com> (raw)
From: Wang Dongsheng <dongsheng.wang@freescale.com>
When the timer GTCCR toggle bit is inverted, we calculated the rest
of the time is not accurate. So we need to ignore this bit.
Signed-off-by: Wang Dongsheng <dongsheng.wang@freescale.com>
---
v2:
No change.
diff --git a/arch/powerpc/sysdev/mpic_timer.c b/arch/powerpc/sysdev/mpic_timer.c
index 22d7d57..70dcf9c 100644
--- a/arch/powerpc/sysdev/mpic_timer.c
+++ b/arch/powerpc/sysdev/mpic_timer.c
@@ -41,6 +41,7 @@
#define MPIC_TIMER_TCR_ROVR_OFFSET 24
#define TIMER_STOP 0x80000000
+#define GTCCR_TOG 0x80000000
#define TIMERS_PER_GROUP 4
#define MAX_TICKS (~0U >> 1)
#define MAX_TICKS_CASCADE (~0U)
@@ -327,11 +328,13 @@ void mpic_get_remain_time(struct mpic_timer *handle, struct timeval *time)
casc_priv = priv->timer[handle->num].cascade_handle;
if (casc_priv) {
tmp_ticks = in_be32(&priv->regs[handle->num].gtccr);
+ tmp_ticks &= ~GTCCR_TOG;
ticks = ((u64)tmp_ticks & UINT_MAX) * (u64)MAX_TICKS_CASCADE;
tmp_ticks = in_be32(&priv->regs[handle->num - 1].gtccr);
ticks += tmp_ticks;
} else {
ticks = in_be32(&priv->regs[handle->num].gtccr);
+ ticks &= ~GTCCR_TOG;
}
convert_ticks_to_time(priv, ticks, time);
--
1.8.5
next reply other threads:[~2014-01-06 5:27 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-01-06 5:23 Dongsheng Wang [this message]
2014-01-06 5:23 ` [PATCH v2 2/2] powerpc/mpic_timer: fix convert ticks to time subtraction overflow Dongsheng Wang
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=1388985811-32495-1-git-send-email-dongsheng.wang@freescale.com \
--to=dongsheng.wang@freescale.com \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=scottwood@freescale.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).