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Message-ID: <87po0ssxx5.wl%kuninori.morimoto.gx@renesas.com>
From:   Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
To:     Vinod Koul <vinod.koul@linaro.org>
Cc:     Geert Uytterhoeven <geert@linux-m68k.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Magnus Damm <magnus.damm@gmail.com>,
        Linux-Renesas <linux-renesas-soc@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Kieran Bingham <kieran@ksquared.org.uk>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        dmaengine@vger.kernel.org,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>
Subject: Re: [PATCH v2] dmaengine: rcar-dmac: don't use DMAC error interrupt
In-Reply-To: <20180614083425.GA25852@vkoul-mobl>
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        <20180614083425.GA25852@vkoul-mobl>
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Date:   Fri, 15 Jun 2018 00:24:45 +0000
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Hi Vinod

Thank you for your feedback

> > From: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
> > 
> > Current rcar-dmac is using DMAC error interrupt which will handle all
> > channel's error. But in this design, error handling itself will be
> > issue if user want to use virtualization, multi OS, etc.
> > This patch removes current DMAC error interrupt handling, and handle it
> > on each channel interrupt handler.
> 
> So what happens when you are not in virtualization, multi OS..? Who
> handles this interrupt?

Sorry for non clear English
It has 2types of interrupt.
 1) IRQ for Error
 2) IRQ for each channels

If error happens on some channels,
the error IRQ was handled by 1), and "all" channels will be restarted.
Thus, this patch removes 1), and handles each error on 2).

Best regards
---
Kuninori Morimoto