arch/arm64/include/asm/io.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Based on arch/arm/include/asm/io.h
   4  *
   5  * Copyright (C) 1996-2000 Russell King
   6  * Copyright (C) 2012 ARM Ltd.
   7  */
   8 #ifndef __ASM_IO_H
   9 #define __ASM_IO_H
  10
  11 #include <linux/types.h>
  12
  13 #include <asm/byteorder.h>
  14 #include <asm/barrier.h>
  15 #include <asm/memory.h>
  16 #include <asm/pgtable.h>
  17 #include <asm/early_ioremap.h>
  18 #include <asm/alternative.h>
  19 #include <asm/cpufeature.h>
  20
  21 /*
  22  * Generic IO read/write.  These perform native-endian accesses.
  23  */
  24 #define __raw_writeb __raw_writeb
  25 static inline void __raw_writeb(u8 val, volatile void __iomem *addr)
  26 {
  27         asm volatile("strb %w0, [%1]" : : "rZ" (val), "r" (addr));
  28 }
  29
  30 #define __raw_writew __raw_writew
  31 static inline void __raw_writew(u16 val, volatile void __iomem *addr)
  32 {
  33         asm volatile("strh %w0, [%1]" : : "rZ" (val), "r" (addr));
  34 }
  35
  36 #define __raw_writel __raw_writel
  37 static inline void __raw_writel(u32 val, volatile void __iomem *addr)
  38 {
  39         asm volatile("str %w0, [%1]" : : "rZ" (val), "r" (addr));
  40 }
  41
  42 #define __raw_writeq __raw_writeq
  43 static inline void __raw_writeq(u64 val, volatile void __iomem *addr)
  44 {
  45         asm volatile("str %x0, [%1]" : : "rZ" (val), "r" (addr));
  46 }
  47
  48 #define __raw_readb __raw_readb
  49 static inline u8 __raw_readb(const volatile void __iomem *addr)
  50 {
  51         u8 val;
  52         asm volatile(ALTERNATIVE("ldrb %w0, [%1]",
  53                                  "ldarb %w0, [%1]",
  54                                  ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
  55                      : "=r" (val) : "r" (addr));
  56         return val;
  57 }
  58
  59 #define __raw_readw __raw_readw
  60 static inline u16 __raw_readw(const volatile void __iomem *addr)
  61 {
  62         u16 val;
  63
  64         asm volatile(ALTERNATIVE("ldrh %w0, [%1]",
  65                                  "ldarh %w0, [%1]",
  66                                  ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
  67                      : "=r" (val) : "r" (addr));
  68         return val;
  69 }
  70
  71 #define __raw_readl __raw_readl
  72 static inline u32 __raw_readl(const volatile void __iomem *addr)
  73 {
  74         u32 val;
  75         asm volatile(ALTERNATIVE("ldr %w0, [%1]",
  76                                  "ldar %w0, [%1]",
  77                                  ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
  78                      : "=r" (val) : "r" (addr));
  79         return val;
  80 }
  81
  82 #define __raw_readq __raw_readq
  83 static inline u64 __raw_readq(const volatile void __iomem *addr)
  84 {
  85         u64 val;
  86         asm volatile(ALTERNATIVE("ldr %0, [%1]",
  87                                  "ldar %0, [%1]",
  88                                  ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE)
  89                      : "=r" (val) : "r" (addr));
  90         return val;
  91 }
  92
  93 /* IO barriers */
  94 #define __iormb(v)                                                      \
  95 ({                                                                      \
  96         unsigned long tmp;                                              \
  97                                                                         \
  98         dma_rmb();                                                              \
  99                                                                         \
 100         /*                                                              \
 101          * Create a dummy control dependency from the IO read to any    \
 102          * later instructions. This ensures that a subsequent call to   \
 103          * udelay() will be ordered due to the ISB in get_cycles().     \
 104          */                                                             \
 105         asm volatile("eor       %0, %1, %1\n"                           \
 106                      "cbnz      %0, ."                                  \
 107                      : "=r" (tmp) : "r" ((unsigned long)(v))            \
 108                      : "memory");                                       \
 109 })
 110
 111 #define __io_par(v)             __iormb(v)
 112 #define __iowmb()               dma_wmb()
 113
 114 /*
 115  * Relaxed I/O memory access primitives. These follow the Device memory
 116  * ordering rules but do not guarantee any ordering relative to Normal memory
 117  * accesses.
 118  */
 119 #define readb_relaxed(c)        ({ u8  __r = __raw_readb(c); __r; })
 120 #define readw_relaxed(c)        ({ u16 __r = le16_to_cpu((__force __le16)__raw_readw(c)); __r; })
 121 #define readl_relaxed(c)        ({ u32 __r = le32_to_cpu((__force __le32)__raw_readl(c)); __r; })
 122 #define readq_relaxed(c)        ({ u64 __r = le64_to_cpu((__force __le64)__raw_readq(c)); __r; })
 123
 124 #define writeb_relaxed(v,c)     ((void)__raw_writeb((v),(c)))
 125 #define writew_relaxed(v,c)     ((void)__raw_writew((__force u16)cpu_to_le16(v),(c)))
 126 #define writel_relaxed(v,c)     ((void)__raw_writel((__force u32)cpu_to_le32(v),(c)))
 127 #define writeq_relaxed(v,c)     ((void)__raw_writeq((__force u64)cpu_to_le64(v),(c)))
 128
 129 /*
 130  * I/O memory access primitives. Reads are ordered relative to any
 131  * following Normal memory access. Writes are ordered relative to any prior
 132  * Normal memory access.
 133  */
 134 #define readb(c)                ({ u8  __v = readb_relaxed(c); __iormb(__v); __v; })
 135 #define readw(c)                ({ u16 __v = readw_relaxed(c); __iormb(__v); __v; })
 136 #define readl(c)                ({ u32 __v = readl_relaxed(c); __iormb(__v); __v; })
 137 #define readq(c)                ({ u64 __v = readq_relaxed(c); __iormb(__v); __v; })
 138
 139 #define writeb(v,c)             ({ __iowmb(); writeb_relaxed((v),(c)); })
 140 #define writew(v,c)             ({ __iowmb(); writew_relaxed((v),(c)); })
 141 #define writel(v,c)             ({ __iowmb(); writel_relaxed((v),(c)); })
 142 #define writeq(v,c)             ({ __iowmb(); writeq_relaxed((v),(c)); })
 143
 144 /*
 145  *  I/O port access primitives.
 146  */
 147 #define arch_has_dev_port()     (1)
 148 #define IO_SPACE_LIMIT          (PCI_IO_SIZE - 1)
 149 #define PCI_IOBASE              ((void __iomem *)PCI_IO_START)
 150
 151 /*
 152  * String version of I/O memory access operations.
 153  */
 154 extern void __memcpy_fromio(void *, const volatile void __iomem *, size_t);
 155 extern void __memcpy_toio(volatile void __iomem *, const void *, size_t);
 156 extern void __memset_io(volatile void __iomem *, int, size_t);
 157
 158 #define memset_io(c,v,l)        __memset_io((c),(v),(l))
 159 #define memcpy_fromio(a,c,l)    __memcpy_fromio((a),(c),(l))
 160 #define memcpy_toio(c,a,l)      __memcpy_toio((c),(a),(l))
 161
 162 /*
 163  * I/O memory mapping functions.
 164  */
 165 extern void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot);
 166 extern void iounmap(volatile void __iomem *addr);
 167 extern void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size);
 168
 169 #define ioremap(addr, size)             __ioremap((addr), (size), __pgprot(PROT_DEVICE_nGnRE))
 170 #define ioremap_wc(addr, size)          __ioremap((addr), (size), __pgprot(PROT_NORMAL_NC))
 171
 172 /*
 173  * PCI configuration space mapping function.
 174  *
 175  * The PCI specification disallows posted write configuration transactions.
 176  * Add an arch specific pci_remap_cfgspace() definition that is implemented
 177  * through nGnRnE device memory attribute as recommended by the ARM v8
 178  * Architecture reference manual Issue A.k B2.8.2 "Device memory".
 179  */
 180 #define pci_remap_cfgspace(addr, size) __ioremap((addr), (size), __pgprot(PROT_DEVICE_nGnRnE))
 181
 182 /*
 183  * io{read,write}{16,32,64}be() macros
 184  */
 185 #define ioread16be(p)           ({ __u16 __v = be16_to_cpu((__force __be16)__raw_readw(p)); __iormb(__v); __v; })
 186 #define ioread32be(p)           ({ __u32 __v = be32_to_cpu((__force __be32)__raw_readl(p)); __iormb(__v); __v; })
 187 #define ioread64be(p)           ({ __u64 __v = be64_to_cpu((__force __be64)__raw_readq(p)); __iormb(__v); __v; })
 188
 189 #define iowrite16be(v,p)        ({ __iowmb(); __raw_writew((__force __u16)cpu_to_be16(v), p); })
 190 #define iowrite32be(v,p)        ({ __iowmb(); __raw_writel((__force __u32)cpu_to_be32(v), p); })
 191 #define iowrite64be(v,p)        ({ __iowmb(); __raw_writeq((__force __u64)cpu_to_be64(v), p); })
 192
 193 #include <asm-generic/io.h>
 194
 195 /*
 196  * More restrictive address range checking than the default implementation
 197  * (PHYS_OFFSET and PHYS_MASK taken into account).
 198  */
 199 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
 200 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
 201 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
 202
 203 extern int devmem_is_allowed(unsigned long pfn);
 204
 205 #endif  /* __ASM_IO_H */