arch/c6x/include/asm/uaccess.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  *  Copyright (C) 2011 Texas Instruments Incorporated
   4  *  Author: Mark Salter <msalter@redhat.com>
   5  */
   6 #ifndef _ASM_C6X_UACCESS_H
   7 #define _ASM_C6X_UACCESS_H
   8
   9 #include <linux/types.h>
  10 #include <linux/compiler.h>
  11 #include <linux/string.h>
  12
  13 /*
  14  * C6X supports unaligned 32 and 64 bit loads and stores.
  15  */
  16 static inline __must_check unsigned long
  17 raw_copy_from_user(void *to, const void __user *from, unsigned long n)
  18 {
  19         u32 tmp32;
  20         u64 tmp64;
  21
  22         if (__builtin_constant_p(n)) {
  23                 switch (n) {
  24                 case 1:
  25                         *(u8 *)to = *(u8 __force *)from;
  26                         return 0;
  27                 case 4:
  28                         asm volatile ("ldnw .d1t1 *%2,%0\n"
  29                                       "nop  4\n"
  30                                       "stnw .d1t1 %0,*%1\n"
  31                                       : "=&a"(tmp32)
  32                                       : "A"(to), "a"(from)
  33                                       : "memory");
  34                         return 0;
  35                 case 8:
  36                         asm volatile ("ldndw .d1t1 *%2,%0\n"
  37                                       "nop   4\n"
  38                                       "stndw .d1t1 %0,*%1\n"
  39                                       : "=&a"(tmp64)
  40                                       : "a"(to), "a"(from)
  41                                       : "memory");
  42                         return 0;
  43                 default:
  44                         break;
  45                 }
  46         }
  47
  48         memcpy(to, (const void __force *)from, n);
  49         return 0;
  50 }
  51
  52 static inline __must_check unsigned long
  53 raw_copy_to_user(void __user *to, const void *from, unsigned long n)
  54 {
  55         u32 tmp32;
  56         u64 tmp64;
  57
  58         if (__builtin_constant_p(n)) {
  59                 switch (n) {
  60                 case 1:
  61                         *(u8 __force *)to = *(u8 *)from;
  62                         return 0;
  63                 case 4:
  64                         asm volatile ("ldnw .d1t1 *%2,%0\n"
  65                                       "nop  4\n"
  66                                       "stnw .d1t1 %0,*%1\n"
  67                                       : "=&a"(tmp32)
  68                                       : "a"(to), "a"(from)
  69                                       : "memory");
  70                         return 0;
  71                 case 8:
  72                         asm volatile ("ldndw .d1t1 *%2,%0\n"
  73                                       "nop   4\n"
  74                                       "stndw .d1t1 %0,*%1\n"
  75                                       : "=&a"(tmp64)
  76                                       : "a"(to), "a"(from)
  77                                       : "memory");
  78                         return 0;
  79                 default:
  80                         break;
  81                 }
  82         }
  83
  84         memcpy((void __force *)to, from, n);
  85         return 0;
  86 }
  87 #define INLINE_COPY_FROM_USER
  88 #define INLINE_COPY_TO_USER
  89
  90 extern int _access_ok(unsigned long addr, unsigned long size);
  91 #ifdef CONFIG_ACCESS_CHECK
  92 #define __access_ok _access_ok
  93 #endif
  94
  95 #include <asm-generic/uaccess.h>
  96
  97 #endif /* _ASM_C6X_UACCESS_H */