kernel-ark/include/asm-xtensa/io.h
Chris Zankel 6656920b0b [XTENSA] Add support for cache-aliasing
Add support for processors that have cache-aliasing issues, such as
the Stretch S5000 processor. Cache-aliasing means that the size of
the cache (for one way) is larger than the page size, thus, a page
can end up in several places in cache depending on the virtual to
physical translation. The method used here is to map a user page
temporarily through the auto-refill way 0 and of of the DTLB.
We probably will want to revisit this issue and use a better
approach with kmap/kunmap.

Signed-off-by: Chris Zankel <chris@zankel.net>
2007-08-27 13:54:16 -07:00

199 lines
5.6 KiB
C

/*
* include/asm-xtensa/io.h
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001 - 2005 Tensilica Inc.
*/
#ifndef _XTENSA_IO_H
#define _XTENSA_IO_H
#ifdef __KERNEL__
#include <asm/byteorder.h>
#include <asm/page.h>
#include <linux/kernel.h>
#include <linux/types.h>
#define XCHAL_KIO_CACHED_VADDR 0xf0000000
#define XCHAL_KIO_BYPASS_VADDR 0xf8000000
#define XCHAL_KIO_PADDR 0xf0000000
#define XCHAL_KIO_SIZE 0x08000000
/*
* swap functions to change byte order from little-endian to big-endian and
* vice versa.
*/
static inline unsigned short _swapw (unsigned short v)
{
return (v << 8) | (v >> 8);
}
static inline unsigned int _swapl (unsigned int v)
{
return (v << 24) | ((v & 0xff00) << 8) | ((v >> 8) & 0xff00) | (v >> 24);
}
/*
* Change virtual addresses to physical addresses and vv.
* These are trivial on the 1:1 Linux/Xtensa mapping
*/
static inline unsigned long virt_to_phys(volatile void * address)
{
return __pa(address);
}
static inline void * phys_to_virt(unsigned long address)
{
return __va(address);
}
/*
* virt_to_bus and bus_to_virt are deprecated.
*/
#define virt_to_bus(x) virt_to_phys(x)
#define bus_to_virt(x) phys_to_virt(x)
/*
* Return the virtual (cached) address for the specified bus memory.
* Note that we currently don't support any address outside the KIO segment.
*/
static inline void *ioremap(unsigned long offset, unsigned long size)
{
if (offset >= XCHAL_KIO_PADDR
&& offset < XCHAL_KIO_PADDR + XCHAL_KIO_SIZE)
return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_BYPASS_VADDR);
else
BUG();
}
static inline void *ioremap_nocache(unsigned long offset, unsigned long size)
{
if (offset >= XCHAL_KIO_PADDR
&& offset < XCHAL_KIO_PADDR + XCHAL_KIO_SIZE)
return (void*)(offset-XCHAL_KIO_PADDR+XCHAL_KIO_CACHED_VADDR);
else
BUG();
}
static inline void iounmap(void *addr)
{
}
/*
* Generic I/O
*/
#define readb(addr) \
({ unsigned char __v = (*(volatile unsigned char *)(addr)); __v; })
#define readw(addr) \
({ unsigned short __v = (*(volatile unsigned short *)(addr)); __v; })
#define readl(addr) \
({ unsigned int __v = (*(volatile unsigned int *)(addr)); __v; })
#define writeb(b, addr) (void)((*(volatile unsigned char *)(addr)) = (b))
#define writew(b, addr) (void)((*(volatile unsigned short *)(addr)) = (b))
#define writel(b, addr) (void)((*(volatile unsigned int *)(addr)) = (b))
static inline __u8 __raw_readb(const volatile void __iomem *addr)
{
return *(__force volatile __u8 *)(addr);
}
static inline __u16 __raw_readw(const volatile void __iomem *addr)
{
return *(__force volatile __u16 *)(addr);
}
static inline __u32 __raw_readl(const volatile void __iomem *addr)
{
return *(__force volatile __u32 *)(addr);
}
static inline void __raw_writeb(__u8 b, volatile void __iomem *addr)
{
*(__force volatile __u8 *)(addr) = b;
}
static inline void __raw_writew(__u16 b, volatile void __iomem *addr)
{
*(__force volatile __u16 *)(addr) = b;
}
static inline void __raw_writel(__u32 b, volatile void __iomem *addr)
{
*(__force volatile __u32 *)(addr) = b;
}
/* These are the definitions for the x86 IO instructions
* inb/inw/inl/outb/outw/outl, the "string" versions
* insb/insw/insl/outsb/outsw/outsl, and the "pausing" versions
* inb_p/inw_p/...
* The macros don't do byte-swapping.
*/
#define inb(port) readb((u8 *)((port)))
#define outb(val, port) writeb((val),(u8 *)((unsigned long)(port)))
#define inw(port) readw((u16 *)((port)))
#define outw(val, port) writew((val),(u16 *)((unsigned long)(port)))
#define inl(port) readl((u32 *)((port)))
#define outl(val, port) writel((val),(u32 *)((unsigned long)(port)))
#define inb_p(port) inb((port))
#define outb_p(val, port) outb((val), (port))
#define inw_p(port) inw((port))
#define outw_p(val, port) outw((val), (port))
#define inl_p(port) inl((port))
#define outl_p(val, port) outl((val), (port))
extern void insb (unsigned long port, void *dst, unsigned long count);
extern void insw (unsigned long port, void *dst, unsigned long count);
extern void insl (unsigned long port, void *dst, unsigned long count);
extern void outsb (unsigned long port, const void *src, unsigned long count);
extern void outsw (unsigned long port, const void *src, unsigned long count);
extern void outsl (unsigned long port, const void *src, unsigned long count);
#define IO_SPACE_LIMIT ~0
#define memset_io(a,b,c) memset((void *)(a),(b),(c))
#define memcpy_fromio(a,b,c) memcpy((a),(void *)(b),(c))
#define memcpy_toio(a,b,c) memcpy((void *)(a),(b),(c))
/* At this point the Xtensa doesn't provide byte swap instructions */
#ifdef __XTENSA_EB__
# define in_8(addr) (*(u8*)(addr))
# define in_le16(addr) _swapw(*(u16*)(addr))
# define in_le32(addr) _swapl(*(u32*)(addr))
# define out_8(b, addr) *(u8*)(addr) = (b)
# define out_le16(b, addr) *(u16*)(addr) = _swapw(b)
# define out_le32(b, addr) *(u32*)(addr) = _swapl(b)
#elif defined(__XTENSA_EL__)
# define in_8(addr) (*(u8*)(addr))
# define in_le16(addr) (*(u16*)(addr))
# define in_le32(addr) (*(u32*)(addr))
# define out_8(b, addr) *(u8*)(addr) = (b)
# define out_le16(b, addr) *(u16*)(addr) = (b)
# define out_le32(b, addr) *(u32*)(addr) = (b)
#else
# error processor byte order undefined!
#endif
/*
* Convert a physical pointer to a virtual kernel pointer for /dev/mem access
*/
#define xlate_dev_mem_ptr(p) __va(p)
/*
* Convert a virtual cached pointer to an uncached pointer
*/
#define xlate_dev_kmem_ptr(p) p
#endif /* __KERNEL__ */
#endif /* _XTENSA_IO_H */