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-rw-r--r--include/asm-generic/io.h1142
1 files changed, 1142 insertions, 0 deletions
diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
new file mode 100644
index 000000000..dcbd41048
--- /dev/null
+++ b/include/asm-generic/io.h
@@ -0,0 +1,1142 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Generic I/O port emulation.
+ *
+ * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+#ifndef __ASM_GENERIC_IO_H
+#define __ASM_GENERIC_IO_H
+
+#include <asm/page.h> /* I/O is all done through memory accesses */
+#include <linux/string.h> /* for memset() and memcpy() */
+#include <linux/types.h>
+
+#ifdef CONFIG_GENERIC_IOMAP
+#include <asm-generic/iomap.h>
+#endif
+
+#include <asm/mmiowb.h>
+#include <asm-generic/pci_iomap.h>
+
+#ifndef __io_br
+#define __io_br() barrier()
+#endif
+
+/* prevent prefetching of coherent DMA data ahead of a dma-complete */
+#ifndef __io_ar
+#ifdef rmb
+#define __io_ar(v) rmb()
+#else
+#define __io_ar(v) barrier()
+#endif
+#endif
+
+/* flush writes to coherent DMA data before possibly triggering a DMA read */
+#ifndef __io_bw
+#ifdef wmb
+#define __io_bw() wmb()
+#else
+#define __io_bw() barrier()
+#endif
+#endif
+
+/* serialize device access against a spin_unlock, usually handled there. */
+#ifndef __io_aw
+#define __io_aw() mmiowb_set_pending()
+#endif
+
+#ifndef __io_pbw
+#define __io_pbw() __io_bw()
+#endif
+
+#ifndef __io_paw
+#define __io_paw() __io_aw()
+#endif
+
+#ifndef __io_pbr
+#define __io_pbr() __io_br()
+#endif
+
+#ifndef __io_par
+#define __io_par(v) __io_ar(v)
+#endif
+
+
+/*
+ * __raw_{read,write}{b,w,l,q}() access memory in native endianness.
+ *
+ * On some architectures memory mapped IO needs to be accessed differently.
+ * On the simple architectures, we just read/write the memory location
+ * directly.
+ */
+
+#ifndef __raw_readb
+#define __raw_readb __raw_readb
+static inline u8 __raw_readb(const volatile void __iomem *addr)
+{
+ return *(const volatile u8 __force *)addr;
+}
+#endif
+
+#ifndef __raw_readw
+#define __raw_readw __raw_readw
+static inline u16 __raw_readw(const volatile void __iomem *addr)
+{
+ return *(const volatile u16 __force *)addr;
+}
+#endif
+
+#ifndef __raw_readl
+#define __raw_readl __raw_readl
+static inline u32 __raw_readl(const volatile void __iomem *addr)
+{
+ return *(const volatile u32 __force *)addr;
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef __raw_readq
+#define __raw_readq __raw_readq
+static inline u64 __raw_readq(const volatile void __iomem *addr)
+{
+ return *(const volatile u64 __force *)addr;
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef __raw_writeb
+#define __raw_writeb __raw_writeb
+static inline void __raw_writeb(u8 value, volatile void __iomem *addr)
+{
+ *(volatile u8 __force *)addr = value;
+}
+#endif
+
+#ifndef __raw_writew
+#define __raw_writew __raw_writew
+static inline void __raw_writew(u16 value, volatile void __iomem *addr)
+{
+ *(volatile u16 __force *)addr = value;
+}
+#endif
+
+#ifndef __raw_writel
+#define __raw_writel __raw_writel
+static inline void __raw_writel(u32 value, volatile void __iomem *addr)
+{
+ *(volatile u32 __force *)addr = value;
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef __raw_writeq
+#define __raw_writeq __raw_writeq
+static inline void __raw_writeq(u64 value, volatile void __iomem *addr)
+{
+ *(volatile u64 __force *)addr = value;
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+/*
+ * {read,write}{b,w,l,q}() access little endian memory and return result in
+ * native endianness.
+ */
+
+#ifndef readb
+#define readb readb
+static inline u8 readb(const volatile void __iomem *addr)
+{
+ u8 val;
+
+ __io_br();
+ val = __raw_readb(addr);
+ __io_ar(val);
+ return val;
+}
+#endif
+
+#ifndef readw
+#define readw readw
+static inline u16 readw(const volatile void __iomem *addr)
+{
+ u16 val;
+
+ __io_br();
+ val = __le16_to_cpu((__le16 __force)__raw_readw(addr));
+ __io_ar(val);
+ return val;
+}
+#endif
+
+#ifndef readl
+#define readl readl
+static inline u32 readl(const volatile void __iomem *addr)
+{
+ u32 val;
+
+ __io_br();
+ val = __le32_to_cpu((__le32 __force)__raw_readl(addr));
+ __io_ar(val);
+ return val;
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef readq
+#define readq readq
+static inline u64 readq(const volatile void __iomem *addr)
+{
+ u64 val;
+
+ __io_br();
+ val = __le64_to_cpu((__le64 __force)__raw_readq(addr));
+ __io_ar(val);
+ return val;
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef writeb
+#define writeb writeb
+static inline void writeb(u8 value, volatile void __iomem *addr)
+{
+ __io_bw();
+ __raw_writeb(value, addr);
+ __io_aw();
+}
+#endif
+
+#ifndef writew
+#define writew writew
+static inline void writew(u16 value, volatile void __iomem *addr)
+{
+ __io_bw();
+ __raw_writew((u16 __force)cpu_to_le16(value), addr);
+ __io_aw();
+}
+#endif
+
+#ifndef writel
+#define writel writel
+static inline void writel(u32 value, volatile void __iomem *addr)
+{
+ __io_bw();
+ __raw_writel((u32 __force)__cpu_to_le32(value), addr);
+ __io_aw();
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef writeq
+#define writeq writeq
+static inline void writeq(u64 value, volatile void __iomem *addr)
+{
+ __io_bw();
+ __raw_writeq((u64 __force)__cpu_to_le64(value), addr);
+ __io_aw();
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+/*
+ * {read,write}{b,w,l,q}_relaxed() are like the regular version, but
+ * are not guaranteed to provide ordering against spinlocks or memory
+ * accesses.
+ */
+#ifndef readb_relaxed
+#define readb_relaxed readb_relaxed
+static inline u8 readb_relaxed(const volatile void __iomem *addr)
+{
+ return __raw_readb(addr);
+}
+#endif
+
+#ifndef readw_relaxed
+#define readw_relaxed readw_relaxed
+static inline u16 readw_relaxed(const volatile void __iomem *addr)
+{
+ return __le16_to_cpu(__raw_readw(addr));
+}
+#endif
+
+#ifndef readl_relaxed
+#define readl_relaxed readl_relaxed
+static inline u32 readl_relaxed(const volatile void __iomem *addr)
+{
+ return __le32_to_cpu(__raw_readl(addr));
+}
+#endif
+
+#if defined(readq) && !defined(readq_relaxed)
+#define readq_relaxed readq_relaxed
+static inline u64 readq_relaxed(const volatile void __iomem *addr)
+{
+ return __le64_to_cpu(__raw_readq(addr));
+}
+#endif
+
+#ifndef writeb_relaxed
+#define writeb_relaxed writeb_relaxed
+static inline void writeb_relaxed(u8 value, volatile void __iomem *addr)
+{
+ __raw_writeb(value, addr);
+}
+#endif
+
+#ifndef writew_relaxed
+#define writew_relaxed writew_relaxed
+static inline void writew_relaxed(u16 value, volatile void __iomem *addr)
+{
+ __raw_writew(cpu_to_le16(value), addr);
+}
+#endif
+
+#ifndef writel_relaxed
+#define writel_relaxed writel_relaxed
+static inline void writel_relaxed(u32 value, volatile void __iomem *addr)
+{
+ __raw_writel(__cpu_to_le32(value), addr);
+}
+#endif
+
+#if defined(writeq) && !defined(writeq_relaxed)
+#define writeq_relaxed writeq_relaxed
+static inline void writeq_relaxed(u64 value, volatile void __iomem *addr)
+{
+ __raw_writeq(__cpu_to_le64(value), addr);
+}
+#endif
+
+/*
+ * {read,write}s{b,w,l,q}() repeatedly access the same memory address in
+ * native endianness in 8-, 16-, 32- or 64-bit chunks (@count times).
+ */
+#ifndef readsb
+#define readsb readsb
+static inline void readsb(const volatile void __iomem *addr, void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ u8 *buf = buffer;
+
+ do {
+ u8 x = __raw_readb(addr);
+ *buf++ = x;
+ } while (--count);
+ }
+}
+#endif
+
+#ifndef readsw
+#define readsw readsw
+static inline void readsw(const volatile void __iomem *addr, void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ u16 *buf = buffer;
+
+ do {
+ u16 x = __raw_readw(addr);
+ *buf++ = x;
+ } while (--count);
+ }
+}
+#endif
+
+#ifndef readsl
+#define readsl readsl
+static inline void readsl(const volatile void __iomem *addr, void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ u32 *buf = buffer;
+
+ do {
+ u32 x = __raw_readl(addr);
+ *buf++ = x;
+ } while (--count);
+ }
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef readsq
+#define readsq readsq
+static inline void readsq(const volatile void __iomem *addr, void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ u64 *buf = buffer;
+
+ do {
+ u64 x = __raw_readq(addr);
+ *buf++ = x;
+ } while (--count);
+ }
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef writesb
+#define writesb writesb
+static inline void writesb(volatile void __iomem *addr, const void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ const u8 *buf = buffer;
+
+ do {
+ __raw_writeb(*buf++, addr);
+ } while (--count);
+ }
+}
+#endif
+
+#ifndef writesw
+#define writesw writesw
+static inline void writesw(volatile void __iomem *addr, const void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ const u16 *buf = buffer;
+
+ do {
+ __raw_writew(*buf++, addr);
+ } while (--count);
+ }
+}
+#endif
+
+#ifndef writesl
+#define writesl writesl
+static inline void writesl(volatile void __iomem *addr, const void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ const u32 *buf = buffer;
+
+ do {
+ __raw_writel(*buf++, addr);
+ } while (--count);
+ }
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef writesq
+#define writesq writesq
+static inline void writesq(volatile void __iomem *addr, const void *buffer,
+ unsigned int count)
+{
+ if (count) {
+ const u64 *buf = buffer;
+
+ do {
+ __raw_writeq(*buf++, addr);
+ } while (--count);
+ }
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef PCI_IOBASE
+#define PCI_IOBASE ((void __iomem *)0)
+#endif
+
+#ifndef IO_SPACE_LIMIT
+#define IO_SPACE_LIMIT 0xffff
+#endif
+
+/*
+ * {in,out}{b,w,l}() access little endian I/O. {in,out}{b,w,l}_p() can be
+ * implemented on hardware that needs an additional delay for I/O accesses to
+ * take effect.
+ */
+
+#if !defined(inb) && !defined(_inb)
+#define _inb _inb
+static inline u8 _inb(unsigned long addr)
+{
+ u8 val;
+
+ __io_pbr();
+ val = __raw_readb(PCI_IOBASE + addr);
+ __io_par(val);
+ return val;
+}
+#endif
+
+#if !defined(inw) && !defined(_inw)
+#define _inw _inw
+static inline u16 _inw(unsigned long addr)
+{
+ u16 val;
+
+ __io_pbr();
+ val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
+ __io_par(val);
+ return val;
+}
+#endif
+
+#if !defined(inl) && !defined(_inl)
+#define _inl _inl
+static inline u32 _inl(unsigned long addr)
+{
+ u32 val;
+
+ __io_pbr();
+ val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
+ __io_par(val);
+ return val;
+}
+#endif
+
+#if !defined(outb) && !defined(_outb)
+#define _outb _outb
+static inline void _outb(u8 value, unsigned long addr)
+{
+ __io_pbw();
+ __raw_writeb(value, PCI_IOBASE + addr);
+ __io_paw();
+}
+#endif
+
+#if !defined(outw) && !defined(_outw)
+#define _outw _outw
+static inline void _outw(u16 value, unsigned long addr)
+{
+ __io_pbw();
+ __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
+ __io_paw();
+}
+#endif
+
+#if !defined(outl) && !defined(_outl)
+#define _outl _outl
+static inline void _outl(u32 value, unsigned long addr)
+{
+ __io_pbw();
+ __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
+ __io_paw();
+}
+#endif
+
+#include <linux/logic_pio.h>
+
+#ifndef inb
+#define inb _inb
+#endif
+
+#ifndef inw
+#define inw _inw
+#endif
+
+#ifndef inl
+#define inl _inl
+#endif
+
+#ifndef outb
+#define outb _outb
+#endif
+
+#ifndef outw
+#define outw _outw
+#endif
+
+#ifndef outl
+#define outl _outl
+#endif
+
+#ifndef inb_p
+#define inb_p inb_p
+static inline u8 inb_p(unsigned long addr)
+{
+ return inb(addr);
+}
+#endif
+
+#ifndef inw_p
+#define inw_p inw_p
+static inline u16 inw_p(unsigned long addr)
+{
+ return inw(addr);
+}
+#endif
+
+#ifndef inl_p
+#define inl_p inl_p
+static inline u32 inl_p(unsigned long addr)
+{
+ return inl(addr);
+}
+#endif
+
+#ifndef outb_p
+#define outb_p outb_p
+static inline void outb_p(u8 value, unsigned long addr)
+{
+ outb(value, addr);
+}
+#endif
+
+#ifndef outw_p
+#define outw_p outw_p
+static inline void outw_p(u16 value, unsigned long addr)
+{
+ outw(value, addr);
+}
+#endif
+
+#ifndef outl_p
+#define outl_p outl_p
+static inline void outl_p(u32 value, unsigned long addr)
+{
+ outl(value, addr);
+}
+#endif
+
+/*
+ * {in,out}s{b,w,l}{,_p}() are variants of the above that repeatedly access a
+ * single I/O port multiple times.
+ */
+
+#ifndef insb
+#define insb insb
+static inline void insb(unsigned long addr, void *buffer, unsigned int count)
+{
+ readsb(PCI_IOBASE + addr, buffer, count);
+}
+#endif
+
+#ifndef insw
+#define insw insw
+static inline void insw(unsigned long addr, void *buffer, unsigned int count)
+{
+ readsw(PCI_IOBASE + addr, buffer, count);
+}
+#endif
+
+#ifndef insl
+#define insl insl
+static inline void insl(unsigned long addr, void *buffer, unsigned int count)
+{
+ readsl(PCI_IOBASE + addr, buffer, count);
+}
+#endif
+
+#ifndef outsb
+#define outsb outsb
+static inline void outsb(unsigned long addr, const void *buffer,
+ unsigned int count)
+{
+ writesb(PCI_IOBASE + addr, buffer, count);
+}
+#endif
+
+#ifndef outsw
+#define outsw outsw
+static inline void outsw(unsigned long addr, const void *buffer,
+ unsigned int count)
+{
+ writesw(PCI_IOBASE + addr, buffer, count);
+}
+#endif
+
+#ifndef outsl
+#define outsl outsl
+static inline void outsl(unsigned long addr, const void *buffer,
+ unsigned int count)
+{
+ writesl(PCI_IOBASE + addr, buffer, count);
+}
+#endif
+
+#ifndef insb_p
+#define insb_p insb_p
+static inline void insb_p(unsigned long addr, void *buffer, unsigned int count)
+{
+ insb(addr, buffer, count);
+}
+#endif
+
+#ifndef insw_p
+#define insw_p insw_p
+static inline void insw_p(unsigned long addr, void *buffer, unsigned int count)
+{
+ insw(addr, buffer, count);
+}
+#endif
+
+#ifndef insl_p
+#define insl_p insl_p
+static inline void insl_p(unsigned long addr, void *buffer, unsigned int count)
+{
+ insl(addr, buffer, count);
+}
+#endif
+
+#ifndef outsb_p
+#define outsb_p outsb_p
+static inline void outsb_p(unsigned long addr, const void *buffer,
+ unsigned int count)
+{
+ outsb(addr, buffer, count);
+}
+#endif
+
+#ifndef outsw_p
+#define outsw_p outsw_p
+static inline void outsw_p(unsigned long addr, const void *buffer,
+ unsigned int count)
+{
+ outsw(addr, buffer, count);
+}
+#endif
+
+#ifndef outsl_p
+#define outsl_p outsl_p
+static inline void outsl_p(unsigned long addr, const void *buffer,
+ unsigned int count)
+{
+ outsl(addr, buffer, count);
+}
+#endif
+
+#ifndef CONFIG_GENERIC_IOMAP
+#ifndef ioread8
+#define ioread8 ioread8
+static inline u8 ioread8(const volatile void __iomem *addr)
+{
+ return readb(addr);
+}
+#endif
+
+#ifndef ioread16
+#define ioread16 ioread16
+static inline u16 ioread16(const volatile void __iomem *addr)
+{
+ return readw(addr);
+}
+#endif
+
+#ifndef ioread32
+#define ioread32 ioread32
+static inline u32 ioread32(const volatile void __iomem *addr)
+{
+ return readl(addr);
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef ioread64
+#define ioread64 ioread64
+static inline u64 ioread64(const volatile void __iomem *addr)
+{
+ return readq(addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef iowrite8
+#define iowrite8 iowrite8
+static inline void iowrite8(u8 value, volatile void __iomem *addr)
+{
+ writeb(value, addr);
+}
+#endif
+
+#ifndef iowrite16
+#define iowrite16 iowrite16
+static inline void iowrite16(u16 value, volatile void __iomem *addr)
+{
+ writew(value, addr);
+}
+#endif
+
+#ifndef iowrite32
+#define iowrite32 iowrite32
+static inline void iowrite32(u32 value, volatile void __iomem *addr)
+{
+ writel(value, addr);
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef iowrite64
+#define iowrite64 iowrite64
+static inline void iowrite64(u64 value, volatile void __iomem *addr)
+{
+ writeq(value, addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef ioread16be
+#define ioread16be ioread16be
+static inline u16 ioread16be(const volatile void __iomem *addr)
+{
+ return swab16(readw(addr));
+}
+#endif
+
+#ifndef ioread32be
+#define ioread32be ioread32be
+static inline u32 ioread32be(const volatile void __iomem *addr)
+{
+ return swab32(readl(addr));
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef ioread64be
+#define ioread64be ioread64be
+static inline u64 ioread64be(const volatile void __iomem *addr)
+{
+ return swab64(readq(addr));
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef iowrite16be
+#define iowrite16be iowrite16be
+static inline void iowrite16be(u16 value, void volatile __iomem *addr)
+{
+ writew(swab16(value), addr);
+}
+#endif
+
+#ifndef iowrite32be
+#define iowrite32be iowrite32be
+static inline void iowrite32be(u32 value, volatile void __iomem *addr)
+{
+ writel(swab32(value), addr);
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef iowrite64be
+#define iowrite64be iowrite64be
+static inline void iowrite64be(u64 value, volatile void __iomem *addr)
+{
+ writeq(swab64(value), addr);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef ioread8_rep
+#define ioread8_rep ioread8_rep
+static inline void ioread8_rep(const volatile void __iomem *addr, void *buffer,
+ unsigned int count)
+{
+ readsb(addr, buffer, count);
+}
+#endif
+
+#ifndef ioread16_rep
+#define ioread16_rep ioread16_rep
+static inline void ioread16_rep(const volatile void __iomem *addr,
+ void *buffer, unsigned int count)
+{
+ readsw(addr, buffer, count);
+}
+#endif
+
+#ifndef ioread32_rep
+#define ioread32_rep ioread32_rep
+static inline void ioread32_rep(const volatile void __iomem *addr,
+ void *buffer, unsigned int count)
+{
+ readsl(addr, buffer, count);
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef ioread64_rep
+#define ioread64_rep ioread64_rep
+static inline void ioread64_rep(const volatile void __iomem *addr,
+ void *buffer, unsigned int count)
+{
+ readsq(addr, buffer, count);
+}
+#endif
+#endif /* CONFIG_64BIT */
+
+#ifndef iowrite8_rep
+#define iowrite8_rep iowrite8_rep
+static inline void iowrite8_rep(volatile void __iomem *addr,
+ const void *buffer,
+ unsigned int count)
+{
+ writesb(addr, buffer, count);
+}
+#endif
+
+#ifndef iowrite16_rep
+#define iowrite16_rep iowrite16_rep
+static inline void iowrite16_rep(volatile void __iomem *addr,
+ const void *buffer,
+ unsigned int count)
+{
+ writesw(addr, buffer, count);
+}
+#endif
+
+#ifndef iowrite32_rep
+#define iowrite32_rep iowrite32_rep
+static inline void iowrite32_rep(volatile void __iomem *addr,
+ const void *buffer,
+ unsigned int count)
+{
+ writesl(addr, buffer, count);
+}
+#endif
+
+#ifdef CONFIG_64BIT
+#ifndef iowrite64_rep
+#define iowrite64_rep iowrite64_rep
+static inline void iowrite64_rep(volatile void __iomem *addr,
+ const void *buffer,
+ unsigned int count)
+{
+ writesq(addr, buffer, count);
+}
+#endif
+#endif /* CONFIG_64BIT */
+#endif /* CONFIG_GENERIC_IOMAP */
+
+#ifdef __KERNEL__
+
+#include <linux/vmalloc.h>
+#define __io_virt(x) ((void __force *)(x))
+
+/*
+ * Change virtual addresses to physical addresses and vv.
+ * These are pretty trivial
+ */
+#ifndef virt_to_phys
+#define virt_to_phys virt_to_phys
+static inline unsigned long virt_to_phys(volatile void *address)
+{
+ return __pa((unsigned long)address);
+}
+#endif
+
+#ifndef phys_to_virt
+#define phys_to_virt phys_to_virt
+static inline void *phys_to_virt(unsigned long address)
+{
+ return __va(address);
+}
+#endif
+
+/**
+ * DOC: ioremap() and ioremap_*() variants
+ *
+ * Architectures with an MMU are expected to provide ioremap() and iounmap()
+ * themselves or rely on GENERIC_IOREMAP. For NOMMU architectures we provide
+ * a default nop-op implementation that expect that the physical address used
+ * for MMIO are already marked as uncached, and can be used as kernel virtual
+ * addresses.
+ *
+ * ioremap_wc() and ioremap_wt() can provide more relaxed caching attributes
+ * for specific drivers if the architecture choses to implement them. If they
+ * are not implemented we fall back to plain ioremap.
+ */
+#ifndef CONFIG_MMU
+#ifndef ioremap
+#define ioremap ioremap
+static inline void __iomem *ioremap(phys_addr_t offset, size_t size)
+{
+ return (void __iomem *)(unsigned long)offset;
+}
+#endif
+
+#ifndef iounmap
+#define iounmap iounmap
+static inline void iounmap(void __iomem *addr)
+{
+}
+#endif
+#elif defined(CONFIG_GENERIC_IOREMAP)
+#include <linux/pgtable.h>
+
+void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot);
+void iounmap(volatile void __iomem *addr);
+
+static inline void __iomem *ioremap(phys_addr_t addr, size_t size)
+{
+ /* _PAGE_IOREMAP needs to be supplied by the architecture */
+ return ioremap_prot(addr, size, _PAGE_IOREMAP);
+}
+#endif /* !CONFIG_MMU || CONFIG_GENERIC_IOREMAP */
+
+#ifndef ioremap_wc
+#define ioremap_wc ioremap
+#endif
+
+#ifndef ioremap_wt
+#define ioremap_wt ioremap
+#endif
+
+/*
+ * ioremap_uc is special in that we do require an explicit architecture
+ * implementation. In general you do not want to use this function in a
+ * driver and use plain ioremap, which is uncached by default. Similarly
+ * architectures should not implement it unless they have a very good
+ * reason.
+ */
+#ifndef ioremap_uc
+#define ioremap_uc ioremap_uc
+static inline void __iomem *ioremap_uc(phys_addr_t offset, size_t size)
+{
+ return NULL;
+}
+#endif
+
+#ifdef CONFIG_HAS_IOPORT_MAP
+#ifndef CONFIG_GENERIC_IOMAP
+#ifndef ioport_map
+#define ioport_map ioport_map
+static inline void __iomem *ioport_map(unsigned long port, unsigned int nr)
+{
+ port &= IO_SPACE_LIMIT;
+ return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port;
+}
+#define __pci_ioport_unmap __pci_ioport_unmap
+static inline void __pci_ioport_unmap(void __iomem *p)
+{
+ uintptr_t start = (uintptr_t) PCI_IOBASE;
+ uintptr_t addr = (uintptr_t) p;
+
+ if (addr >= start && addr < start + IO_SPACE_LIMIT)
+ return;
+ iounmap(p);
+}
+#endif
+
+#ifndef ioport_unmap
+#define ioport_unmap ioport_unmap
+static inline void ioport_unmap(void __iomem *p)
+{
+}
+#endif
+#else /* CONFIG_GENERIC_IOMAP */
+extern void __iomem *ioport_map(unsigned long port, unsigned int nr);
+extern void ioport_unmap(void __iomem *p);
+#endif /* CONFIG_GENERIC_IOMAP */
+#endif /* CONFIG_HAS_IOPORT_MAP */
+
+#ifndef CONFIG_GENERIC_IOMAP
+struct pci_dev;
+extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max);
+
+#ifndef __pci_ioport_unmap
+static inline void __pci_ioport_unmap(void __iomem *p) {}
+#endif
+
+#ifndef pci_iounmap
+#define pci_iounmap pci_iounmap
+static inline void pci_iounmap(struct pci_dev *dev, void __iomem *p)
+{
+ __pci_ioport_unmap(p);
+}
+#endif
+#endif /* CONFIG_GENERIC_IOMAP */
+
+/*
+ * Convert a virtual cached pointer to an uncached pointer
+ */
+#ifndef xlate_dev_kmem_ptr
+#define xlate_dev_kmem_ptr xlate_dev_kmem_ptr
+static inline void *xlate_dev_kmem_ptr(void *addr)
+{
+ return addr;
+}
+#endif
+
+#ifndef xlate_dev_mem_ptr
+#define xlate_dev_mem_ptr xlate_dev_mem_ptr
+static inline void *xlate_dev_mem_ptr(phys_addr_t addr)
+{
+ return __va(addr);
+}
+#endif
+
+#ifndef unxlate_dev_mem_ptr
+#define unxlate_dev_mem_ptr unxlate_dev_mem_ptr
+static inline void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
+{
+}
+#endif
+
+#ifdef CONFIG_VIRT_TO_BUS
+#ifndef virt_to_bus
+static inline unsigned long virt_to_bus(void *address)
+{
+ return (unsigned long)address;
+}
+
+static inline void *bus_to_virt(unsigned long address)
+{
+ return (void *)address;
+}
+#endif
+#endif
+
+#ifndef memset_io
+#define memset_io memset_io
+/**
+ * memset_io Set a range of I/O memory to a constant value
+ * @addr: The beginning of the I/O-memory range to set
+ * @val: The value to set the memory to
+ * @count: The number of bytes to set
+ *
+ * Set a range of I/O memory to a given value.
+ */
+static inline void memset_io(volatile void __iomem *addr, int value,
+ size_t size)
+{
+ memset(__io_virt(addr), value, size);
+}
+#endif
+
+#ifndef memcpy_fromio
+#define memcpy_fromio memcpy_fromio
+/**
+ * memcpy_fromio Copy a block of data from I/O memory
+ * @dst: The (RAM) destination for the copy
+ * @src: The (I/O memory) source for the data
+ * @count: The number of bytes to copy
+ *
+ * Copy a block of data from I/O memory.
+ */
+static inline void memcpy_fromio(void *buffer,
+ const volatile void __iomem *addr,
+ size_t size)
+{
+ memcpy(buffer, __io_virt(addr), size);
+}
+#endif
+
+#ifndef memcpy_toio
+#define memcpy_toio memcpy_toio
+/**
+ * memcpy_toio Copy a block of data into I/O memory
+ * @dst: The (I/O memory) destination for the copy
+ * @src: The (RAM) source for the data
+ * @count: The number of bytes to copy
+ *
+ * Copy a block of data to I/O memory.
+ */
+static inline void memcpy_toio(volatile void __iomem *addr, const void *buffer,
+ size_t size)
+{
+ memcpy(__io_virt(addr), buffer, size);
+}
+#endif
+
+#endif /* __KERNEL__ */
+
+#endif /* __ASM_GENERIC_IO_H */