[PATCH] serial: DCC(JTAG) serial and console emulation support
Tony Lindgren
tony at atomide.com
Thu Oct 7 17:27:07 EDT 2010
Hi,
* Daniel Walker <dwalker at codeaurora.org> [101005 11:59]:
> +#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
Can you please pass the read and write functions to the driver
in platform_data? We are already booting kernels with both
ARMv6 and 7 compiled in.
Also, as it's a driver, other architectures may want to use it too.
Regards,
Tony
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