root/arch/powerpc/include/asm/page_32.h

INCLUDED FROM

DEFINITIONS

1. clear_page

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_POWERPC_PAGE_32_H
   3 #define _ASM_POWERPC_PAGE_32_H
   4 
   5 #include <asm/cache.h>
   6 
   7 #if defined(CONFIG_PHYSICAL_ALIGN) && (CONFIG_PHYSICAL_START != 0)
   8 #if (CONFIG_PHYSICAL_START % CONFIG_PHYSICAL_ALIGN) != 0
   9 #error "CONFIG_PHYSICAL_START must be a multiple of CONFIG_PHYSICAL_ALIGN"
  10 #endif
  11 #endif
  12 
  13 #define VM_DATA_DEFAULT_FLAGS   VM_DATA_DEFAULT_FLAGS32
  14 
  15 #ifdef CONFIG_NOT_COHERENT_CACHE
  16 #define ARCH_DMA_MINALIGN       L1_CACHE_BYTES
  17 #endif
  18 
  19 #ifdef CONFIG_PTE_64BIT
  20 #define PTE_FLAGS_OFFSET        4       /* offset of PTE flags, in bytes */
  21 #else
  22 #define PTE_FLAGS_OFFSET        0
  23 #endif
  24 
  25 #if defined(CONFIG_PPC_256K_PAGES) || \
  26     (defined(CONFIG_PPC_8xx) && defined(CONFIG_PPC_16K_PAGES))
  27 #define PTE_SHIFT       (PAGE_SHIFT - PTE_T_LOG2 - 2)   /* 1/4 of a page */
  28 #else
  29 #define PTE_SHIFT       (PAGE_SHIFT - PTE_T_LOG2)       /* full page */
  30 #endif
  31 
  32 #ifndef __ASSEMBLY__
  33 /*
  34  * The basic type of a PTE - 64 bits for those CPUs with > 32 bit
  35  * physical addressing.
  36  */
  37 #ifdef CONFIG_PTE_64BIT
  38 typedef unsigned long long pte_basic_t;
  39 #else
  40 typedef unsigned long pte_basic_t;
  41 #endif
  42 
  43 #include <asm/bug.h>
  44 
  45 /*
  46  * Clear page using the dcbz instruction, which doesn't cause any
  47  * memory traffic (except to write out any cache lines which get
  48  * displaced).  This only works on cacheable memory.
  49  */
  50 static inline void clear_page(void *addr)
  51 {
  52         unsigned int i;
  53 
  54         WARN_ON((unsigned long)addr & (L1_CACHE_BYTES - 1));
  55 
  56         for (i = 0; i < PAGE_SIZE / L1_CACHE_BYTES; i++, addr += L1_CACHE_BYTES)
  57                 dcbz(addr);
  58 }
  59 extern void copy_page(void *to, void *from);
  60 
  61 #include <asm-generic/getorder.h>
  62 
  63 #define PGD_T_LOG2      (__builtin_ffs(sizeof(pgd_t)) - 1)
  64 #define PTE_T_LOG2      (__builtin_ffs(sizeof(pte_t)) - 1)
  65 
  66 #endif /* __ASSEMBLY__ */
  67 
  68 #endif /* _ASM_POWERPC_PAGE_32_H */