> --- arch/alpha/pci/pci_swiz_bus_io_chipdep.c.orig	Wed Nov 26 16:47:51 1997
> +++ arch/alpha/pci/pci_swiz_bus_io_chipdep.c	Fri Nov 28 15:25:43 1997
> @@ -646,11 +646,44 @@
>  	bus_size_t o, c;						\
>  	const TYPE *a;							\
>  {									\
> +	/* Check for unaligned access to memory */			\
> +	if ((BYTES > 1) && ( ((u_int64_t)a) & (BYTES-1) ) ) {		\
> +	    TYPE d;							\
> +	    int  i;							\
>  									\
> -	while (c-- > 0) {						\
> -		__C(__C(CHIP,_io_write_),BYTES)(v, h, o, *a++);		\
> -		__C(CHIP,_io_barrier)(v, h, o, sizeof *a,		\
> -		    BUS_BARRIER_WRITE);					\
> +	    if (((u_int64_t)a) & 1) {					\
> +		while (c-- > 0) {					\
> +			for (i = 0; i < BYTES; i++)			\
> +				((u_int8_t *)&d)[i] = *((u_int8_t *)a)++; \
> +			__C(__C(CHIP,_io_write_),BYTES)(v, h, o, d);	\
> +			__C(CHIP,_io_barrier)(v, h, o, sizeof *a,	\
> +			    BUS_BARRIER_WRITE);				\
> +		}							\
> +	    }								\
> +	    else if ((BYTES > 2) && (((u_int64_t)a) & 2)) {		\
> +		while (c-- > 0) {					\
> +			for (i = 0; i < BYTES/2; i++)			\
> +				((u_int16_t *)&d)[i] = *((u_int16_t *)a)++; \
> +			__C(__C(CHIP,_io_write_),BYTES)(v, h, o, d);	\
> +			__C(CHIP,_io_barrier)(v, h, o, sizeof *a,	\
> +			    BUS_BARRIER_WRITE);				\
> +		}							\
> +	    }								\
> +	    else if ((BYTES > 4) && (((u_int64_t)a) & 4)) {		\
> +		while (c-- > 0) {					\
> +			for (i = 0; i < BYTES/4; i++)			\
> +				((u_int32_t *)&d)[i] = *((u_int32_t *)a)++; \
> +			__C(__C(CHIP,_io_write_),BYTES)(v, h, o, d);	\
> +			__C(CHIP,_io_barrier)(v, h, o, sizeof *a,	\
> +			    BUS_BARRIER_WRITE);				\
> +		}							\
> +	    }								\
> +	} else {							\
> +		while (c-- > 0) {					\
> +			__C(__C(CHIP,_io_write_),BYTES)(v, h, o, *a++);	\
> +			__C(CHIP,_io_barrier)(v, h, o, sizeof *a,	\
> +			    BUS_BARRIER_WRITE);				\
> +		}							\
>  	}								\
>  }
>  CHIP_io_write_multi_N(1,u_int8_t)

This is not appropriate, and should not be necessary.

It is a driver bug to call the bus_space_* macros with an
improperly-aligned pointer.  It should not have to be, and should not
be, worked around in the bus_space_* implementation.  Rather, it
should be fixed in the driver.


cgd