diff options
Diffstat (limited to 'include/asm-alpha/floppy.h')
| -rw-r--r-- | include/asm-alpha/floppy.h | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/include/asm-alpha/floppy.h b/include/asm-alpha/floppy.h index 39c1e491c..2f847ddb0 100644 --- a/include/asm-alpha/floppy.h +++ b/include/asm-alpha/floppy.h @@ -53,13 +53,24 @@ static int FDC2 = -1; #define FLOPPY_MOTOR_MASK 0xf0 /* - * Most Alphas have no problems with floppy DMA crossing 64k borders. Sigh... + * Most Alphas have no problems with floppy DMA crossing 64k borders, + * except for XL. It is also the only one with DMA limits, so we use + * that to test in the generic kernel. */ -#ifdef CONFIG_ALPHA_XL -#define CROSS_64KB(a,s) \ - ((unsigned long)(a)/0x10000 != ((unsigned long)(a) + (s) - 1) / 0x10000) -#else /* CONFIG_ALPHA_XL */ -#define CROSS_64KB(a,s) (0) -#endif /* CONFIG_ALPHA_XL */ + +#define __CROSS_64KB(a,s) \ +({ unsigned long __s64 = (unsigned long)(a); \ + unsigned long __e64 = __s64 + (unsigned long)(s) - 1; \ + (__s64 ^ __e64) & ~0xfffful; }) + +#ifdef CONFIG_ALPHA_GENERIC +# define CROSS_64KB(a,s) (__CROSS_64KB(a,s) && ~alpha_mv.max_dma_address) +#else +# ifdef CONFIG_ALPHA_XL +# define CROSS_64KB(a,s) __CROSS_64KB(a,s) +# else +# define CROSS_64KB(a,s) (0) +# endif +#endif #endif /* __ASM_ALPHA_FLOPPY_H */ |