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    SubjectRe: [PATCH take #5] [libata] libata driver for bf548 on chip ATAPI controller.
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    On Thu, 2007-08-16 at 14:56 -0400, Jeff Garzik wrote:
    > Mike Frysinger wrote:
    > > On 8/16/07, Jeff Garzik <jeff@garzik.org> wrote:
    > >> Mike Frysinger wrote:
    > >>> On 8/16/07, Jeff Garzik <jeff@garzik.org> wrote:
    > >>>> Sonic Zhang wrote:
    > >>>>> +static void bfin_set_piomode(struct ata_port *ap, struct ata_device *adev)
    > >>>>> +{
    > >>>>> + int mode = adev->pio_mode - XFER_PIO_0;
    > >>>>> + unsigned long base = (unsigned long)ap->ioaddr.ctl_addr;
    > >>>> (added Bryan Wu to CC)
    > >>>>
    > >>>> Someone needs to need fix the bfin architecture: the addresses on the
    > >>>> bfin_read/bfin_write functions should be 'void __iomem *' not unsigned long.
    > >>> there are no address pointers anymore, so there is nothing to cast ...
    > >>> the bfin_read/bfin_write macros are done in sexy asm:
    > >>> #define bfin_write8(addr,val) __asm__ __volatile__("b[%0] = %1;" ::
    > >>> "a"(addr), "d"(val))
    > >>> or i'm misunderstanding what you mean ...
    > >>>
    > >>> where do you see (unsigned long) ?
    > >> Look up (into the message you quoted).
    > >
    > > yes, you quoted the driver, not the Blackfin core parts
    > >
    > >> Regardless of the implementation, the C type system should be employed
    > >> to ensure that 'addr' is known to the compiler as 'void __iomem *'
    > >> rather than unsigned long.
    > >
    > > i agree the specific pata driver should be declared the way you
    > > described, however i dont see how that has bearing on the
    > > bfin_read/bfin_write macros as you seemed to indicate
    >
    > Macros completely ignore the C type system. Look at other architectures
    > if you cannot figure out how to implement a static inline with stronger
    > typing.
    >
    > Jeff
    >

    Yes, Jeff is right. Type checking in C is very useful.

    So,
    a) our register access function: bfin_read8/16/32 and bfin_write8/16/32
    macros should be change to inline functions.
    b) the "addr" should be defined as "void __iomem *"
    c) in these functions it may use the sexy asm stuff

    How do you think of this, Mike? And am I right, Jeff?

    Thanks
    - Bryan Wu
    >
    -
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