[rtc-linux] Re: [PATCH] Remove __raw_* accessors from PL031 RTC

Linus Walleij linus.ml.walleij at gmail.com
Sun Nov 15 17:09:36 EST 2009

2009/11/15 Uwe Kleine-König <u.kleine-koenig at pengutronix.de>:

> arch/arm/include/asm/io.h defines writel like so:
>        #define writel(v,c)             __raw_writel((__force __u32) \
>                                                cpu_to_le32(v),__mem_pci(c))
> So this change isn't a noop on big-endian systems that define __mem_pci.
> I don't know how many of these exist though.

Yeah it's not supposed to be a noop, it's supposed to be a bugfix, all
other PrimeCell drivers use readl()/writel(). The assumption is that PrimeCell
registers shall always be accessed LE, and AFAICT that's what the above
macro does.


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