Re: [PATCH v5 07/29] nios2: I/O Mapping

From: Arnd Bergmann
Date: Tue Oct 28 2014 - 09:30:43 EST


On Friday 24 October 2014 16:24:09 Ley Foon Tan wrote:

> +/* PCI is not supported in nios2, set this to 0. */
> +#define IO_SPACE_LIMIT 0
> +
> +extern void outsb(unsigned long addr, const void *buf, int len);
> +extern void outsw(unsigned long addr, const void *buf, int len);
> +extern void outsl(unsigned long addr, const void *buf, int len);
> +extern void insb(unsigned long addr, void *buf, int len);
> +extern void insw(unsigned long addr, void *buf, int len);
> +extern void insl(unsigned long addr, void *buf, int len);
> +#define outsb outsb
> +#define outsw outsw
> +#define outsl outsl
> +#define insb insb
> +#define insw insw
> +#define insl insl

You don't have inb/outb, so you shouldn't have these either.

> +/*
> + * PCI is not enabled in nios2. Provide dummy implementation to get 'allyesconfig'
> + * to build successfully.
> + */
> +#define inb(addr) ({ 0; })
> +#define inw(addr) ({ 0; })
> +#define inl(addr) ({ 0; })
> +#define outb(x, addr) do { } while (0)
> +#define outw(x, addr) do { } while (0)
> +#define outl(x, addr) do { } while (0)

What fails if you take these out?

> +
> +/* Use "Duff's Device" to unroll the loops. */
> +#define __IO_OUT_LOOP(a, b, l) \
> + do { \
> + if (l > 0) { \
> + int _n = (l + 7) / 8; \
> + switch (l % 8) { \
> + case 0: \
> + do { \
> + *a = *b++; \
> + case 7: \
> + *a = *b++; \
> + case 6: \
> + *a = *b++; \
> + case 5: \
> + *a = *b++; \
> + case 4: \
> + *a = *b++; \
> + case 3: \
> + *a = *b++; \
> + case 2: \
> + *a = *b++; \
> + case 1: \
> + *a = *b++; \
> + } while (--_n > 0); \
> + } \
> + } \
> + } while (0)
> +
> +#define __IO_IN_LOOP(a, b, l) \
> + do { \
> + if (l > 0) { \
> + int _n = (l + 7) / 8; \
> + switch (l % 8) { \
> + case 0: \
> + do { \
> + *b++ = *a; \
> + case 7: \
> + *b++ = *a; \
> + case 6: \
> + *b++ = *a; \
> + case 5: \
> + *b++ = *a; \
> + case 4: \
> + *b++ = *a; \
> + case 3: \
> + *b++ = *a; \
> + case 2: \
> + *b++ = *a; \
> + case 1: \
> + *b++ = *a; \
> + } while (--_n > 0); \
> + } \
> + } \
> + } while (0)
> +
> +#else /* __IO_USE_DUFFS */
> +
> +/* Use simple loops. */
> +#define __IO_OUT_LOOP(a, b, l) \
> + do { \
> + while (l--) \
> + *a = *b++; \
> + } while (0)
> +
> +#define __IO_IN_LOOP(a, b, l) \
> + do { \
> + while (l--) \
> + *b++ = *a; \
> + } while (0)
> +
> +#endif /* __IO_USE_DUFFS */
> +
> +void outsb(unsigned long addr, const void *buf, int len)
> +{
> + volatile unsigned char *ap = (volatile unsigned char *)addr;
> + unsigned char *bp = (unsigned char *)buf;
> + __IO_OUT_LOOP(ap, bp, len);
> +}
> +EXPORT_SYMBOL(outsb);
> +
> +void outsw(unsigned long addr, const void *buf, int len)
> +{
> + volatile unsigned short *ap = (volatile unsigned short *)addr;
> + unsigned short *bp = (unsigned short *)buf;
> + __IO_OUT_LOOP(ap, bp, len);
> +}
> +EXPORT_SYMBOL(outsw);

This implementation makes no sense, so definitely remove them.


Arnd

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