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 #include <linux/libnvdimm.h>
  10
  11 #include <asm/cacheflush.h>
  12
  13 static inline void __clean_pmem_range(unsigned long start, unsigned long stop)
  14 {
  15         unsigned long shift = l1_dcache_shift();
  16         unsigned long bytes = l1_dcache_bytes();
  17         void *addr = (void *)(start & ~(bytes - 1));
  18         unsigned long size = stop - (unsigned long)addr + (bytes - 1);
  19         unsigned long i;
  20
  21         for (i = 0; i < size >> shift; i++, addr += bytes)
  22                 asm volatile(PPC_DCBSTPS(%0, %1): :"i"(0), "r"(addr): "memory");
  23 }
  24
  25 static inline void __flush_pmem_range(unsigned long start, unsigned long stop)
  26 {
  27         unsigned long shift = l1_dcache_shift();
  28         unsigned long bytes = l1_dcache_bytes();
  29         void *addr = (void *)(start & ~(bytes - 1));
  30         unsigned long size = stop - (unsigned long)addr + (bytes - 1);
  31         unsigned long i;
  32
  33         for (i = 0; i < size >> shift; i++, addr += bytes)
  34                 asm volatile(PPC_DCBFPS(%0, %1): :"i"(0), "r"(addr): "memory");
  35 }
  36
  37 static inline void clean_pmem_range(unsigned long start, unsigned long stop)
  38 {
  39         if (cpu_has_feature(CPU_FTR_ARCH_207S))
  40                 return __clean_pmem_range(start, stop);
  41 }
  42
  43 static inline void flush_pmem_range(unsigned long start, unsigned long stop)
  44 {
  45         if (cpu_has_feature(CPU_FTR_ARCH_207S))
  46                 return __flush_pmem_range(start, stop);
  47 }
  48
  49 /*
  50  * CONFIG_ARCH_HAS_PMEM_API symbols
  51  */
  52 void arch_wb_cache_pmem(void *addr, size_t size)
  53 {
  54         unsigned long start = (unsigned long) addr;
  55         clean_pmem_range(start, start + size);
  56 }
  57 EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
  58
  59 void arch_invalidate_pmem(void *addr, size_t size)
  60 {
  61         unsigned long start = (unsigned long) addr;
  62         flush_pmem_range(start, start + size);
  63 }
  64 EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
  65
  66 /*
  67  * CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE symbols
  68  */
  69 long __copy_from_user_flushcache(void *dest, const void __user *src,
  70                 unsigned size)
  71 {
  72         unsigned long copied, start = (unsigned long) dest;
  73
  74         copied = __copy_from_user(dest, src, size);
  75         clean_pmem_range(start, start + size);
  76
  77         return copied;
  78 }
  79
  80 void memcpy_flushcache(void *dest, const void *src, size_t size)
  81 {
  82         unsigned long start = (unsigned long) dest;
  83
  84         memcpy(dest, src, size);
  85         clean_pmem_range(start, start + size);
  86 }
  87 EXPORT_SYMBOL(memcpy_flushcache);