RE: [PATCH 2/5] Clocksource: Flextimer: Use internal clocksource read API.

From: Li.Xiubo@xxxxxxxxxxxxx
Date: Wed Sep 03 2014 - 21:49:33 EST


> Subject: Re: [PATCH 2/5] Clocksource: Flextimer: Use internal clocksource read
> API.
>
> On Tue, 26 Aug 2014, Xiubo Li wrote:
>
> > Since the Flextimer device will be implemented in BE mode on
> > LS1 SoC, and in LE mode on Vybrid, LS2 SoCs, so here we need
> > the endianness judgment before doing the mmio.
>
> Brilliant. So for every clocksource read you take a conditional.
>
> > @@ -238,7 +243,7 @@ static int __init ftm_clocksource_init(unsigned long
> freq)
> > sched_clock_register(ftm_read_sched_clock, 16, freq / (1 << priv->ps));
> > err = clocksource_mmio_init(priv->clksrc_base + FTM_CNT, "fsl-ftm",
> > freq / (1 << priv->ps), 300, 16,
> > - clocksource_mmio_readl_up);
> > + ftm_clocksource_read_up);
>
> What's wrong with having endianess aware clocksource_mmio functions
> and make the decision at init time?
>

Since the FTM will be in BE mode on LS1 platform, but will be in LE mode
On LS2 platform.

And ftm_clocksource_read_up() will adapt to this different.

Thanks,

BRs
Xiubo
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