From mboxrd@z Thu Jan  1 00:00:00 1970
From: Lucas Stach <l.stach@pengutronix.de>
Subject: Re: [EXT] Re: [PATCH v2 06/15] spi: imx: fix ERR009165
Date: Fri, 26 Apr 2019 11:37:22 +0200
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To: Robin Gong <yibin.gong@nxp.com>,
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Am Freitag, den 26.04.2019, 09:22 +0000 schrieb Robin Gong:
> On 2019-04-26 at 11:07 +0200, Lucas Stach wrote:
> > 
> > Am Freitag, den 26.04.2019, 08:05 +0000 schrieb Robin Gong:
> > >  static void mx51_setup_wml(struct spi_imx_data *spi_imx)
> > >  {
> > > +     u32 tx_wml = 0;
> > > +
> > 
> > With a wml of 0 you might set the maxburst of the TX dma channel to
> > fifosize to minimize the performance impact of this workaround.
> > 
> > Regards,
> > Lucas
> 
> Unfortunately, this is a MUST part of errata which cause performance
> drop.

I'm not talking about changing the WML, but when the WML must be 0 you
can safely increase the DMA burst size without overflowing the FIFO,
which might recover some of of the performance loss.

Regards,
Lucas