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    SubjectRe: [PATCH v3 01/12] misc: add driver for sequencer serial port
    On 10/22/2010 08:48 AM, Arnd Bergmann wrote:
    > On Friday 22 October 2010 14:39:33 Cyril Chemparathy wrote:
    >>>> +/* Register Access Helpers */
    >>>> +static inline u32 ssp_read(struct ti_ssp *ssp, int reg)
    >>>> +{
    >>>> + return __raw_readl(ssp->regs + reg);
    >>>> +}
    >>>> +
    >>>> +static inline void ssp_write(struct ti_ssp *ssp, int reg, u32 val)
    >>>> +{
    >>>> + __raw_writel(val, ssp->regs + reg);
    >>>> +}
    >>>
    >>> Why are the __raw functions used here?
    >>>
    >>
    >> These registers are to be accessed native endian at all times, and
    >> therefore the le32 conversion done otherwise is inappropriate.
    >
    > Won't that break on out-of-order CPUs that need the extra synchronization
    > done in readl/writel?
    >

    AFAICS, ioremap()ed space on ARMv6 should be strongly ordered.

    >
    > ...
    >

    Thanks
    Cyril.


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