arch/powerpc/lib/pmem.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright(c) 2017 IBM Corporation. All rights reserved.
   4  */
   5
   6 #include <linux/string.h>
   7 #include <linux/export.h>
   8 #include <linux/uaccess.h>
   9
  10 #include <asm/cacheflush.h>
  11
  12 static inline void __clean_pmem_range(unsigned long start, unsigned long stop)
  13 {
  14         unsigned long shift = l1_dcache_shift();
  15         unsigned long bytes = l1_dcache_bytes();
  16         void *addr = (void *)(start & ~(bytes - 1));
  17         unsigned long size = stop - (unsigned long)addr + (bytes - 1);
  18         unsigned long i;
  19
  20         for (i = 0; i < size >> shift; i++, addr += bytes)
  21                 asm volatile(PPC_DCBSTPS(%0, %1): :"i"(0), "r"(addr): "memory");
  22 }
  23
  24 static inline void __flush_pmem_range(unsigned long start, unsigned long stop)
  25 {
  26         unsigned long shift = l1_dcache_shift();
  27         unsigned long bytes = l1_dcache_bytes();
  28         void *addr = (void *)(start & ~(bytes - 1));
  29         unsigned long size = stop - (unsigned long)addr + (bytes - 1);
  30         unsigned long i;
  31
  32         for (i = 0; i < size >> shift; i++, addr += bytes)
  33                 asm volatile(PPC_DCBFPS(%0, %1): :"i"(0), "r"(addr): "memory");
  34 }
  35
  36 static inline void clean_pmem_range(unsigned long start, unsigned long stop)
  37 {
  38         if (cpu_has_feature(CPU_FTR_ARCH_207S))
  39                 return __clean_pmem_range(start, stop);
  40 }
  41
  42 static inline void flush_pmem_range(unsigned long start, unsigned long stop)
  43 {
  44         if (cpu_has_feature(CPU_FTR_ARCH_207S))
  45                 return __flush_pmem_range(start, stop);
  46 }
  47
  48 /*
  49  * CONFIG_ARCH_HAS_PMEM_API symbols
  50  */
  51 void arch_wb_cache_pmem(void *addr, size_t size)
  52 {
  53         unsigned long start = (unsigned long) addr;
  54         clean_pmem_range(start, start + size);
  55 }
  56 EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
  57
  58 void arch_invalidate_pmem(void *addr, size_t size)
  59 {
  60         unsigned long start = (unsigned long) addr;
  61         flush_pmem_range(start, start + size);
  62 }
  63 EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
  64
  65 /*
  66  * CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE symbols
  67  */
  68 long __copy_from_user_flushcache(void *dest, const void __user *src,
  69                 unsigned size)
  70 {
  71         unsigned long copied, start = (unsigned long) dest;
  72
  73         copied = __copy_from_user(dest, src, size);
  74         clean_pmem_range(start, start + size);
  75
  76         return copied;
  77 }
  78
  79 void memcpy_flushcache(void *dest, const void *src, size_t size)
  80 {
  81         unsigned long start = (unsigned long) dest;
  82
  83         memcpy(dest, src, size);
  84         clean_pmem_range(start, start + size);
  85 }
  86 EXPORT_SYMBOL(memcpy_flushcache);
  87
  88 void memcpy_page_flushcache(char *to, struct page *page, size_t offset,
  89         size_t len)
  90 {
  91         memcpy_flushcache(to, page_to_virt(page) + offset, len);
  92 }
  93 EXPORT_SYMBOL(memcpy_page_flushcache);