From: Shawn Guo <shawn.guo@linaro.org>
To: Richard Zhao <richard.zhao@freescale.com>
Cc: Richard Zhao <richard.zhao@linaro.org>,
Arnd Bergmann <arnd@arndb.de>,
patches@linaro.org, vinod.koul@intel.com,
linux-kernel@vger.kernel.org, eric.miao@linaro.org,
kernel@pengutronix.de, dan.j.williams@intel.com,
linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v3 2/2] dma/imx-sdma: use writel to write register when enable a channel
Date: Thu, 5 Jan 2012 17:54:15 +0800 [thread overview]
Message-ID: <20120105095413.GD1729@S2101-09.ap.freescale.net> (raw)
In-Reply-To: <20120105091904.GO2414@b20223-02.ap.freescale.net>
On Thu, Jan 05, 2012 at 05:19:05PM +0800, Richard Zhao wrote:
> Russel mentioned that too. But I cannot understand.
> If CONFIG_ARM_DMA_MEM_BUFFERABLE, readl/writel always call rmb/wmb. Do
> we realy need it? It might affect performance.
>
For safety, I think we need it. The operations should be really fast.
--
Regards,
Shawn
prev parent reply other threads:[~2012-01-05 9:44 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-05 7:59 [PATCH v3 0/2] imx-sdma: memory barrier fix Richard Zhao
2012-01-05 7:59 ` [PATCH v3 1/2] dma/imx-sdma: let sdma_run_channel call sdma_enable_channel Richard Zhao
2012-01-05 9:14 ` Shawn Guo
2012-01-05 7:59 ` [PATCH v3 2/2] dma/imx-sdma: use writel to write register when enable a channel Richard Zhao
2012-01-05 9:23 ` Shawn Guo
2012-01-05 9:19 ` Richard Zhao
2012-01-05 9:34 ` Eric Miao
2012-01-05 9:54 ` Shawn Guo [this message]
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