[PATCH] serial: DCC(JTAG) serial and console emulation support
Daniel Walker
dwalker at codeaurora.org
Wed Oct 6 09:48:06 EDT 2010
On Tue, 2010-10-05 at 22:55 -0400, Nicolas Pitre wrote:
> On Tue, 5 Oct 2010, Daniel Walker wrote:
>
> > +#if !defined(CONFIG_CPU_V7)
> > +static inline char
> > +__dcc_getchar(void)
> > +{
> > + char __c;
> > +
> > + asm("mrc p14, 0, %0, c0, c5, 0 @ read comms data reg"
> > + : "=r" (__c) : : "cc");
> > +
> > + return __c;
> > +}
> > +#else
> > +static inline char
> > +__dcc_getchar(void)
> > +{
> > + char __c;
> > +
> > + asm(
> > + "get_wait: mrc p14, 0, pc, c0, c1, 0 \n\
> > + bne get_wait \n\
> > + mrc p14, 0, %0, c0, c5, 0 @ read comms data reg"
> > + : "=r" (__c) : : "cc");
> > +
> > + return __c;
> > +}
> > +#endif
> > +
> > +#if !defined(CONFIG_CPU_V7)
> > +static inline void
> > +__dcc_putchar(char c)
> > +{
> > + asm("mcr p14, 0, %0, c0, c5, 0 @ write a char"
> > + : /* no output register */
> > + : "r" (c) : "cc");
> > +}
> > +#else
> > +static inline void
> > +__dcc_putchar(char c)
> > +{
> > + asm(
> > + "put_wait: mrc p14, 0, pc, c0, c1, 0 \n\
> > + bcs put_wait \n\
> > + mcr p14, 0, %0, c0, c5, 0 "
> > + : : "r" (c) : "cc");
> > +}
> > +#endif
>
> Please move the #ifdef conditionals inside the respective functions so
> to have only one function pair with the various alternatives embedded
> into them.
My typical clean up policy is do to the inverse of what your suggesting.
Mainly because that's the method that I see used extensive in generic
parts of the kernel.
>From my perspective there are pluses an minuses to both. Your method
reduces lines, and duplication. My method makes the code easier to read.
Daniel
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