From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Sugar Zhang <sugar.zhang@rock-chips.com>,
Vinod Koul <vkoul@kernel.org>, Sasha Levin <sashal@kernel.org>,
dmaengine@vger.kernel.org
Subject: [PATCH AUTOSEL 4.9 019/114] dmaengine: pl330: _stop: clear interrupt status
Date: Wed, 22 May 2019 15:28:42 -0400 [thread overview]
Message-ID: <20190522193017.26567-19-sashal@kernel.org> (raw)
In-Reply-To: <20190522193017.26567-1-sashal@kernel.org>
From: Sugar Zhang <sugar.zhang@rock-chips.com>
[ Upstream commit 2da254cc7908105a60a6bb219d18e8dced03dcb9 ]
This patch kill instructs the DMAC to immediately terminate
execution of a thread. and then clear the interrupt status,
at last, stop generating interrupts for DMA_SEV. to guarantee
the next dma start is clean. otherwise, one interrupt maybe leave
to next start and make some mistake.
we can reporduce the problem as follows:
DMASEV: modify the event-interrupt resource, and if the INTEN sets
function as interrupt, the DMAC will set irq<event_num> HIGH to
generate interrupt. write INTCLR to clear interrupt.
DMA EXECUTING INSTRUCTS DMA TERMINATE
| |
| |
... _stop
| |
| spin_lock_irqsave
DMASEV |
| |
| mask INTEN
| |
| DMAKILL
| |
| spin_unlock_irqrestore
in above case, a interrupt was left, and if we unmask INTEN, the DMAC
will set irq<event_num> HIGH to generate interrupt.
to fix this, do as follows:
DMA EXECUTING INSTRUCTS DMA TERMINATE
| |
| |
... _stop
| |
| spin_lock_irqsave
DMASEV |
| |
| DMAKILL
| |
| clear INTCLR
| mask INTEN
| |
| spin_unlock_irqrestore
Signed-off-by: Sugar Zhang <sugar.zhang@rock-chips.com>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/dma/pl330.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index 6d7e3cd4aba4c..57b375d0de292 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -1020,6 +1020,7 @@ static void _stop(struct pl330_thread *thrd)
{
void __iomem *regs = thrd->dmac->base;
u8 insn[6] = {0, 0, 0, 0, 0, 0};
+ u32 inten = readl(regs + INTEN);
if (_state(thrd) == PL330_STATE_FAULT_COMPLETING)
UNTIL(thrd, PL330_STATE_FAULTING | PL330_STATE_KILLING);
@@ -1032,10 +1033,13 @@ static void _stop(struct pl330_thread *thrd)
_emit_KILL(0, insn);
- /* Stop generating interrupts for SEV */
- writel(readl(regs + INTEN) & ~(1 << thrd->ev), regs + INTEN);
-
_execute_DBGINSN(thrd, insn, is_manager(thrd));
+
+ /* clear the event */
+ if (inten & (1 << thrd->ev))
+ writel(1 << thrd->ev, regs + INTCLR);
+ /* Stop generating interrupts for SEV */
+ writel(inten & ~(1 << thrd->ev), regs + INTEN);
}
/* Start doing req 'idx' of thread 'thrd' */
--
2.20.1
next prev parent reply other threads:[~2019-05-22 19:36 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20190522193017.26567-1-sashal@kernel.org>
2019-05-22 19:28 ` [PATCH AUTOSEL 4.9 004/114] dmaengine: tegra210-dma: free dma controller in remove() Sasha Levin
2019-05-22 19:28 ` Sasha Levin [this message]
2019-05-22 19:29 ` [PATCH AUTOSEL 4.9 039/114] dmaengine: at_xdmac: remove BUG_ON macro in tasklet Sasha Levin
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=20190522193017.26567-19-sashal@kernel.org \
--to=sashal@kernel.org \
--cc=dmaengine@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=stable@vger.kernel.org \
--cc=sugar.zhang@rock-chips.com \
--cc=vkoul@kernel.org \
/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).