On 11/24/2013 11:57 AM, Peter Chen wrote:
> On Fri, Nov 22, 2013 at 10:53:53AM +0100, Marc Kleine-Budde wrote:
>> Hello,
>>
>> this series implements the suggested workaround for freescale's imx28 Errata,
>> "ENGR119653 USB: ARM to USB register error issue".
>>
>> changes since v4:
>> - fix signature of imx28_ehci_writel(), don't use volatile, make use of __iomem
>
> The __iomem is just sparse thing, and not related to gcc, our imx28_ehci_writel
> uses assembly directly, and not call writel any more. The definition of
> __raw_writel still uses volatile:
Yes....
>
> include/asm-generic/io.h:
> static inline void __raw_writel(u32 b, volatile void __iomem *addr)
> {
> *(volatile u32 __force *) addr = b;
> }
What does that mean for our imx28_ehci_writel? Do we need volatile here?
> +static inline void imx28_ehci_writel(const unsigned int val, __u32 __iomem *addr)
> +{
> + __asm__ ("swp %0, %0, [%1]" : : "r"(val), "r"(addr));
> +}
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
Vertretung West/Dortmund | Fax: +49-5121-206917-5555 |
Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de |
Attachment:
signature.asc
Description: OpenPGP digital signature
