[PATCH v2] MTD: OneNAND: Fix loop hang when DMA error at Samsung SoCs

Kyungmin Park kmpark at infradead.org
Tue Aug 31 22:28:20 EDT 2010

On Wed, Sep 1, 2010 at 8:02 AM, Artem Bityutskiy <dedekind1 at gmail.com> wrote:
> On Tue, 2010-08-31 at 08:48 +0900, Kyungmin Park wrote:
>>       writel(S5PC110_DMA_TRANS_CMD_TR, base + S5PC110_DMA_TRANS_CMD);
>> +     timeout = jiffies + msec_to_jiffies(20);
> Are you completely absolutely 100% totally sure 20msecs is enough?

Actually there's no mention about the timeout time in the Spec. but I
tested it both s5pc110 and s5pc210. and working well.

No matter increase the time but I give the 4 chance to the DMA
routine. since we got the 5msec times. and in case of s5pc110 it's
implemented the HRT. so it's really enough.

If the DMA takes more time than 20msec, it's really slow devices and
can't use it. as you know the real transfer size is 2KiB or 4KiB.

Thank you,
Kyungmin Park
> --
> Best Regards,
> Artem Bityutskiy (Битюцкий Артём)

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