linux-stable/include/asm-mips/io.h

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/*
* 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) 1994, 1995 Waldorf GmbH
* Copyright (C) 1994 - 2000, 06 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Copyright (C) 2004, 2005 MIPS Technologies, Inc. All rights reserved.
* Author: Maciej W. Rozycki <macro@mips.com>
*/
#ifndef _ASM_IO_H
#define _ASM_IO_H
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <asm/addrspace.h>
#include <asm/byteorder.h>
#include <asm/cpu.h>
#include <asm/cpu-features.h>
#include <asm-generic/iomap.h>
#include <asm/page.h>
#include <asm/pgtable-bits.h>
#include <asm/processor.h>
#include <asm/string.h>
#include <ioremap.h>
#include <mangle-port.h>
/*
* Slowdown I/O port space accesses for antique hardware.
*/
#undef CONF_SLOWDOWN_IO
/*
* Raw operations are never swapped in software. OTOH values that raw
* operations are working on may or may not have been swapped by the bus
* hardware. An example use would be for flash memory that's used for
* execute in place.
*/
# define __raw_ioswabb(a, x) (x)
# define __raw_ioswabw(a, x) (x)
# define __raw_ioswabl(a, x) (x)
# define __raw_ioswabq(a, x) (x)
# define ____raw_ioswabq(a, x) (x)
/* ioswab[bwlq], __mem_ioswab[bwlq] are defined in mangle-port.h */
#define IO_SPACE_LIMIT 0xffff
/*
* On MIPS I/O ports are memory mapped, so we access them using normal
* load/store instructions. mips_io_port_base is the virtual address to
* which all ports are being mapped. For sake of efficiency some code
* assumes that this is an address that can be loaded with a single lui
* instruction, so the lower 16 bits must be zero. Should be true on
* on any sane architecture; generic code does not use this assumption.
*/
extern const unsigned long mips_io_port_base;
/*
* Gcc will generate code to load the value of mips_io_port_base after each
* function call which may be fairly wasteful in some cases. So we don't
* play quite by the book. We tell gcc mips_io_port_base is a long variable
* which solves the code generation issue. Now we need to violate the
* aliasing rules a little to make initialization possible and finally we
* will need the barrier() to fight side effects of the aliasing chat.
* This trickery will eventually collapse under gcc's optimizer. Oh well.
*/
static inline void set_io_port_base(unsigned long base)
{
* (unsigned long *) &mips_io_port_base = base;
barrier();
}
/*
* Thanks to James van Artsdalen for a better timing-fix than
* the two short jumps: using outb's to a nonexistent port seems
* to guarantee better timings even on fast machines.
*
* On the other hand, I'd like to be sure of a non-existent port:
* I feel a bit unsafe about using 0x80 (should be safe, though)
*
* Linus
*
*/
#define __SLOW_DOWN_IO \
__asm__ __volatile__( \
"sb\t$0,0x80(%0)" \
: : "r" (mips_io_port_base));
#ifdef CONF_SLOWDOWN_IO
#ifdef REALLY_SLOW_IO
#define SLOW_DOWN_IO { __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; __SLOW_DOWN_IO; }
#else
#define SLOW_DOWN_IO __SLOW_DOWN_IO
#endif
#else
#define SLOW_DOWN_IO
#endif
/*
* virt_to_phys - map virtual addresses to physical
* @address: address to remap
*
* The returned physical address is the physical (CPU) mapping for
* the memory address given. It is only valid to use this function on
* addresses directly mapped or allocated via kmalloc.
*
* This function does not give bus mappings for DMA transfers. In
* almost all conceivable cases a device driver should not be using
* this function
*/
static inline unsigned long virt_to_phys(volatile const void *address)
{
return (unsigned long)address - PAGE_OFFSET + PHYS_OFFSET;
}
/*
* phys_to_virt - map physical address to virtual
* @address: address to remap
*
* The returned virtual address is a current CPU mapping for
* the memory address given. It is only valid to use this function on
* addresses that have a kernel mapping
*
* This function does not handle bus mappings for DMA transfers. In
* almost all conceivable cases a device driver should not be using
* this function
*/
static inline void * phys_to_virt(unsigned long address)
{
return (void *)(address + PAGE_OFFSET - PHYS_OFFSET);
}
/*
* ISA I/O bus memory addresses are 1:1 with the physical address.
*/
static inline unsigned long isa_virt_to_bus(volatile void * address)
{
return (unsigned long)address - PAGE_OFFSET;
}
static inline void * isa_bus_to_virt(unsigned long address)
{
return (void *)(address + PAGE_OFFSET);
}
#define isa_page_to_bus page_to_phys
/*
* However PCI ones are not necessarily 1:1 and therefore these interfaces
* are forbidden in portable PCI drivers.
*
* Allow them for x86 for legacy drivers, though.
*/
#define virt_to_bus virt_to_phys
#define bus_to_virt phys_to_virt
/*
* isa_slot_offset is the address where E(ISA) busaddress 0 is mapped
* for the processor. This implies the assumption that there is only
* one of these busses.
*/
extern unsigned long isa_slot_offset;
/*
* Change "struct page" to physical address.
*/
#define page_to_phys(page) ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
extern void __iomem * __ioremap(phys_t offset, phys_t size, unsigned long flags);
extern void __iounmap(const volatile void __iomem *addr);
static inline void __iomem * __ioremap_mode(phys_t offset, unsigned long size,
unsigned long flags)
{
void __iomem *addr = plat_ioremap(offset, size, flags);
if (addr)
return addr;
#define __IS_LOW512(addr) (!((phys_t)(addr) & (phys_t) ~0x1fffffffULL))
if (cpu_has_64bit_addresses) {
u64 base = UNCAC_BASE;
/*
* R10000 supports a 2 bit uncached attribute therefore
* UNCAC_BASE may not equal IO_BASE.
*/
if (flags == _CACHE_UNCACHED)
base = (u64) IO_BASE;
return (void __iomem *) (unsigned long) (base + offset);
} else if (__builtin_constant_p(offset) &&
__builtin_constant_p(size) && __builtin_constant_p(flags)) {
phys_t phys_addr, last_addr;
phys_addr = fixup_bigphys_addr(offset, size);
/* Don't allow wraparound or zero size. */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)
return NULL;
/*
* Map uncached objects in the low 512MB of address
* space using KSEG1.
*/
if (__IS_LOW512(phys_addr) && __IS_LOW512(last_addr) &&
flags == _CACHE_UNCACHED)
return (void __iomem *)
(unsigned long)CKSEG1ADDR(phys_addr);
}
return __ioremap(offset, size, flags);
#undef __IS_LOW512
}
/*
* ioremap - map bus memory into CPU space
* @offset: bus address of the memory
* @size: size of the resource to map
*
* ioremap performs a platform specific sequence of operations to
* make bus memory CPU accessible via the readb/readw/readl/writeb/
* writew/writel functions and the other mmio helpers. The returned
* address is not guaranteed to be usable directly as a virtual
* address.
*/
#define ioremap(offset, size) \
__ioremap_mode((offset), (size), _CACHE_UNCACHED)
/*
* ioremap_nocache - map bus memory into CPU space
* @offset: bus address of the memory
* @size: size of the resource to map
*
* ioremap_nocache performs a platform specific sequence of operations to
* make bus memory CPU accessible via the readb/readw/readl/writeb/
* writew/writel functions and the other mmio helpers. The returned
* address is not guaranteed to be usable directly as a virtual
* address.
*
* This version of ioremap ensures that the memory is marked uncachable
* on the CPU as well as honouring existing caching rules from things like
* the PCI bus. Note that there are other caches and buffers on many
* busses. In paticular driver authors should read up on PCI writes
*
* It's useful if some control registers are in such an area and
* write combining or read caching is not desirable:
*/
#define ioremap_nocache(offset, size) \
__ioremap_mode((offset), (size), _CACHE_UNCACHED)
/*
* ioremap_cachable - map bus memory into CPU space
* @offset: bus address of the memory
* @size: size of the resource to map
*
* ioremap_nocache performs a platform specific sequence of operations to
* make bus memory CPU accessible via the readb/readw/readl/writeb/
* writew/writel functions and the other mmio helpers. The returned
* address is not guaranteed to be usable directly as a virtual
* address.
*
* This version of ioremap ensures that the memory is marked cachable by
* the CPU. Also enables full write-combining. Useful for some
* memory-like regions on I/O busses.
*/
#define ioremap_cachable(offset, size) \
__ioremap_mode((offset), (size), _page_cachable_default)
/*
* These two are MIPS specific ioremap variant. ioremap_cacheable_cow
* requests a cachable mapping, ioremap_uncached_accelerated requests a
* mapping using the uncached accelerated mode which isn't supported on
* all processors.
*/
#define ioremap_cacheable_cow(offset, size) \
__ioremap_mode((offset), (size), _CACHE_CACHABLE_COW)
#define ioremap_uncached_accelerated(offset, size) \
__ioremap_mode((offset), (size), _CACHE_UNCACHED_ACCELERATED)
static inline void iounmap(const volatile void __iomem *addr)
{
if (plat_iounmap(addr))
return;
#define __IS_KSEG1(addr) (((unsigned long)(addr) & ~0x1fffffffUL) == CKSEG1)
if (cpu_has_64bit_addresses ||
(__builtin_constant_p(addr) && __IS_KSEG1(addr)))
return;
__iounmap(addr);
#undef __IS_KSEG1
}
#define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, irq) \
\
static inline void pfx##write##bwlq(type val, \
volatile void __iomem *mem) \
{ \
volatile type *__mem; \
type __val; \
\
__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \
\
__val = pfx##ioswab##bwlq(__mem, val); \
\
if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
*__mem = __val; \
else if (cpu_has_64bits) { \
unsigned long __flags; \
type __tmp; \
\
if (irq) \
local_irq_save(__flags); \
__asm__ __volatile__( \
".set mips3" "\t\t# __writeq""\n\t" \
"dsll32 %L0, %L0, 0" "\n\t" \
"dsrl32 %L0, %L0, 0" "\n\t" \
"dsll32 %M0, %M0, 0" "\n\t" \
"or %L0, %L0, %M0" "\n\t" \
"sd %L0, %2" "\n\t" \
".set mips0" "\n" \
: "=r" (__tmp) \
: "0" (__val), "m" (*__mem)); \
if (irq) \
local_irq_restore(__flags); \
} else \
BUG(); \
} \
\
static inline type pfx##read##bwlq(const volatile void __iomem *mem) \
{ \
volatile type *__mem; \
type __val; \
\
__mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \
\
if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
__val = *__mem; \
else if (cpu_has_64bits) { \
unsigned long __flags; \
\
if (irq) \
local_irq_save(__flags); \
__asm__ __volatile__( \
".set mips3" "\t\t# __readq" "\n\t" \
"ld %L0, %1" "\n\t" \
"dsra32 %M0, %L0, 0" "\n\t" \
"sll %L0, %L0, 0" "\n\t" \
".set mips0" "\n" \
: "=r" (__val) \
: "m" (*__mem)); \
if (irq) \
local_irq_restore(__flags); \
} else { \
__val = 0; \
BUG(); \
} \
\
return pfx##ioswab##bwlq(__mem, __val); \
}
#define __BUILD_IOPORT_SINGLE(pfx, bwlq, type, p, slow) \
\
static inline void pfx##out##bwlq##p(type val, unsigned long port) \
{ \
volatile type *__addr; \
type __val; \
\
__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
\
__val = pfx##ioswab##bwlq(__addr, val); \
\
/* Really, we want this to be atomic */ \
BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long)); \
\
*__addr = __val; \
slow; \
} \
\
static inline type pfx##in##bwlq##p(unsigned long port) \
{ \
volatile type *__addr; \
type __val; \
\
__addr = (void *)__swizzle_addr_##bwlq(mips_io_port_base + port); \
\
BUILD_BUG_ON(sizeof(type) > sizeof(unsigned long)); \
\
__val = *__addr; \
slow; \
\
return pfx##ioswab##bwlq(__addr, __val); \
}
#define __BUILD_MEMORY_PFX(bus, bwlq, type) \
\
__BUILD_MEMORY_SINGLE(bus, bwlq, type, 1)
#define BUILDIO_MEM(bwlq, type) \
\
__BUILD_MEMORY_PFX(__raw_, bwlq, type) \
__BUILD_MEMORY_PFX(, bwlq, type) \
__BUILD_MEMORY_PFX(__mem_, bwlq, type) \
BUILDIO_MEM(b, u8)
BUILDIO_MEM(w, u16)
BUILDIO_MEM(l, u32)
BUILDIO_MEM(q, u64)
#define __BUILD_IOPORT_PFX(bus, bwlq, type) \
__BUILD_IOPORT_SINGLE(bus, bwlq, type, ,) \
__BUILD_IOPORT_SINGLE(bus, bwlq, type, _p, SLOW_DOWN_IO)
#define BUILDIO_IOPORT(bwlq, type) \
__BUILD_IOPORT_PFX(, bwlq, type) \
__BUILD_IOPORT_PFX(__mem_, bwlq, type)
BUILDIO_IOPORT(b, u8)
BUILDIO_IOPORT(w, u16)
BUILDIO_IOPORT(l, u32)
#ifdef CONFIG_64BIT
BUILDIO_IOPORT(q, u64)
#endif
#define __BUILDIO(bwlq, type) \
\
__BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 0)
__BUILDIO(q, u64)
#define readb_relaxed readb
#define readw_relaxed readw
#define readl_relaxed readl
#define readq_relaxed readq
/*
* Some code tests for these symbols
*/
#define readq readq
#define writeq writeq
#define __BUILD_MEMORY_STRING(bwlq, type) \
\
static inline void writes##bwlq(volatile void __iomem *mem, \
const void *addr, unsigned int count) \
{ \
const volatile type *__addr = addr; \
\
while (count--) { \
__mem_write##bwlq(*__addr, mem); \
__addr++; \
} \
} \
\
static inline void reads##bwlq(volatile void __iomem *mem, void *addr, \
unsigned int count) \
{ \
volatile type *__addr = addr; \
\
while (count--) { \
*__addr = __mem_read##bwlq(mem); \
__addr++; \
} \
}
#define __BUILD_IOPORT_STRING(bwlq, type) \
\
static inline void outs##bwlq(unsigned long port, const void *addr, \
unsigned int count) \
{ \
const volatile type *__addr = addr; \
\
while (count--) { \
__mem_out##bwlq(*__addr, port); \
__addr++; \
} \
} \
\
static inline void ins##bwlq(unsigned long port, void *addr, \
unsigned int count) \
{ \
volatile type *__addr = addr; \
\
while (count--) { \
*__addr = __mem_in##bwlq(port); \
__addr++; \
} \
}
#define BUILDSTRING(bwlq, type) \
\
__BUILD_MEMORY_STRING(bwlq, type) \
__BUILD_IOPORT_STRING(bwlq, type)
BUILDSTRING(b, u8)
BUILDSTRING(w, u16)
BUILDSTRING(l, u32)
#ifdef CONFIG_64BIT
BUILDSTRING(q, u64)
#endif
/* Depends on MIPS II instruction set */
#define mmiowb() asm volatile ("sync" ::: "memory")
static inline void memset_io(volatile void __iomem *addr, unsigned char val, int count)
{
memset((void __force *) addr, val, count);
}
static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, int count)
{
memcpy(dst, (void __force *) src, count);
}
static inline void memcpy_toio(volatile void __iomem *dst, const void *src, int count)
{
memcpy((void __force *) dst, src, count);
}
/*
* ISA space is 'always mapped' on currently supported MIPS systems, no need
* to explicitly ioremap() it. The fact that the ISA IO space is mapped
* to PAGE_OFFSET is pure coincidence - it does not mean ISA values
* are physical addresses. The following constant pointer can be
* used as the IO-area pointer (it can be iounmapped as well, so the
* analogy with PCI is quite large):
*/
#define __ISA_IO_base ((char *)(isa_slot_offset))
/*
* The caches on some architectures aren't dma-coherent and have need to
* handle this in software. There are three types of operations that
* can be applied to dma buffers.
*
* - dma_cache_wback_inv(start, size) makes caches and coherent by
* writing the content of the caches back to memory, if necessary.
* The function also invalidates the affected part of the caches as
* necessary before DMA transfers from outside to memory.
* - dma_cache_wback(start, size) makes caches and coherent by
* writing the content of the caches back to memory, if necessary.
* The function also invalidates the affected part of the caches as
* necessary before DMA transfers from outside to memory.
* - dma_cache_inv(start, size) invalidates the affected parts of the
* caches. Dirty lines of the caches may be written back or simply
* be discarded. This operation is necessary before dma operations
* to the memory.
*
* This API used to be exported; it now is for arch code internal use only.
*/
#ifdef CONFIG_DMA_NONCOHERENT
extern void (*_dma_cache_wback_inv)(unsigned long start, unsigned long size);
extern void (*_dma_cache_wback)(unsigned long start, unsigned long size);
extern void (*_dma_cache_inv)(unsigned long start, unsigned long size);
#define dma_cache_wback_inv(start, size) _dma_cache_wback_inv(start, size)
#define dma_cache_wback(start, size) _dma_cache_wback(start, size)
#define dma_cache_inv(start, size) _dma_cache_inv(start, size)
#else /* Sane hardware */
#define dma_cache_wback_inv(start,size) \
do { (void) (start); (void) (size); } while (0)
#define dma_cache_wback(start,size) \
do { (void) (start); (void) (size); } while (0)
#define dma_cache_inv(start,size) \
do { (void) (start); (void) (size); } while (0)
#endif /* CONFIG_DMA_NONCOHERENT */
/*
* Read a 32-bit register that requires a 64-bit read cycle on the bus.
* Avoid interrupt mucking, just adjust the address for 4-byte access.
* Assume the addresses are 8-byte aligned.
*/
#ifdef __MIPSEB__
#define __CSR_32_ADJUST 4
#else
#define __CSR_32_ADJUST 0
#endif
#define csr_out32(v, a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST) = (v))
#define csr_in32(a) (*(volatile u32 *)((unsigned long)(a) + __CSR_32_ADJUST))
/*
* 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 /* _ASM_IO_H */