From mboxrd@z Thu Jan  1 00:00:00 1970
From: Liu Ying <Ying.Liu@freescale.com>
Date: Sat, 4 Apr 2015 22:52:44 +0800
Subject: [U-Boot] [PATCH] imx: ipu: fix occasional hang following
 disabling of channel
In-Reply-To: <1428105597-15216-1-git-send-email-tharvey@gateworks.com>
References: <1428105597-15216-1-git-send-email-tharvey@gateworks.com>
Message-ID: <20150404145239.GA2422@vbox>
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To: u-boot@lists.denx.de

Hi Tim,

Does your code base contain this patch[1]?
It probably addressed the same issue you meet.

[1] http://lists.denx.de/pipermail/u-boot/2014-February/174533.html

Regards,
Liu Ying

On Fri, Apr 03, 2015 at 04:59:57PM -0700, Tim Harvey wrote:
> It has been observed that some IMX6SDL SoC will hang appx 0.1% of boots
> between disabling the ipu channel and disabling DMA preceeding an OS boot
> unless an extra delay is added here.
> 
> The specific cause is still under investigation.
> 
> Signed-off-by: Tim Harvey <tharvey@gateworks.com>
> ---
>  drivers/video/ipu_common.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/video/ipu_common.c b/drivers/video/ipu_common.c
> index 5873531..3c1bbbb 100644
> --- a/drivers/video/ipu_common.c
> +++ b/drivers/video/ipu_common.c
> @@ -1109,6 +1109,7 @@ int32_t ipu_disable_channel(ipu_channel_t channel)
>  	if ((channel == MEM_BG_SYNC) || (channel == MEM_FG_SYNC) ||
>  	    (channel == MEM_DC_SYNC)) {
>  		ipu_dp_dc_disable(channel, 0);
> +		mdelay(50);
>  	}
>  
>  	/* Disable DMA channel(s) */
> -- 
> 1.9.1
>