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Date: Mon, 16 Dec 2013 21:00:50 +0800
From: Huang Shijie <shijie8@gmail.com>
To: Elie De Brauwer <eliedebrauwer@gmail.com>
Subject: Re: [PATCH v2] mtd: gpmi: Deal with bitflips in erased regions regions
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Cc: Huang Shijie <b32955@freescale.com>,
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On Mon, Dec 16, 2013 at 10:43:34AM +0100, Elie De Brauwer wrote:
> On Mon, Dec 16, 2013 at 5:30 AM, Huang Shijie <b32955@freescale.com> wrote:
 >> +/* Returns 1 if the last transaction consisted only out of ones. */
> >> +int gpmi_allones(struct gpmi_nand_data *this)
> >> +{
> >> +     struct resources *r = &this->resources;
> >> +     uint32_t reg = readl(r->gpmi_regs + HW_BCH_STATUS0);
> > please add a empty line here.
> >> +     if (reg & BM_BCH_STATUS0_ALLONES_MASK)
> >> +             return 1;
> >> +     return 0;
> > We can simplify the code to:
> >         return reg & BM_BCH_STATUS0_ALLONES_MASK;
> >
> 
> I was doing some stress testing on this piece of code today, but I'm
> afraid the ALLONES solution apparently does not work. If I look at the
> BCH_STATUS0 register while doing some heavy flash access, the
> (entire) register remains zero at all times, while I would at least expect the
how do you do the stress test, and how do you know the register is zero?

I can test it on my side too.

thanks
Huang Shijie