%PDF- %PDF-
Direktori : /proc/self/root/usr/src/linux-headers-5.15.0-125/include/asm-generic/ |
Current File : //proc/self/root/usr/src/linux-headers-5.15.0-125/include/asm-generic/io.h |
/* 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. Conversely, ioremap_np() * can provide stricter non-posted write semantics if the architecture * implements them. */ #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(volatile 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 /* * ioremap_np needs an explicit architecture implementation, as it * requests stronger semantics than regular ioremap(). Portable drivers * should instead use one of the higher-level abstractions, like * devm_ioremap_resource(), to choose the correct variant for any given * device and bus. Portable drivers with a good reason to want non-posted * write semantics should always provide an ioremap() fallback in case * ioremap_np() is not available. */ #ifndef ioremap_np #define ioremap_np ioremap_np static inline void __iomem *ioremap_np(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 ARCH_HAS_GENERIC_IOPORT_MAP #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 #ifndef pci_iounmap #define ARCH_WANTS_GENERIC_PCI_IOUNMAP #endif #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 extern int devmem_is_allowed(unsigned long pfn); #endif /* __KERNEL__ */ #endif /* __ASM_GENERIC_IO_H */