root/arch/powerpc/include/asm/page_64.h

INCLUDED FROM

DEFINITIONS

1. clear_page

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 #ifndef _ASM_POWERPC_PAGE_64_H
   3 #define _ASM_POWERPC_PAGE_64_H
   4 
   5 /*
   6  * Copyright (C) 2001 PPC64 Team, IBM Corp
   7  */
   8 
   9 #include <asm/asm-const.h>
  10 
  11 /*
  12  * We always define HW_PAGE_SHIFT to 12 as use of 64K pages remains Linux
  13  * specific, every notion of page number shared with the firmware, TCEs,
  14  * iommu, etc... still uses a page size of 4K.
  15  */
  16 #define HW_PAGE_SHIFT           12
  17 #define HW_PAGE_SIZE            (ASM_CONST(1) << HW_PAGE_SHIFT)
  18 #define HW_PAGE_MASK            (~(HW_PAGE_SIZE-1))
  19 
  20 /*
  21  * PAGE_FACTOR is the number of bits factor between PAGE_SHIFT and
  22  * HW_PAGE_SHIFT, that is 4K pages.
  23  */
  24 #define PAGE_FACTOR             (PAGE_SHIFT - HW_PAGE_SHIFT)
  25 
  26 /* Segment size; normal 256M segments */
  27 #define SID_SHIFT               28
  28 #define SID_MASK                ASM_CONST(0xfffffffff)
  29 #define ESID_MASK               0xfffffffff0000000UL
  30 #define GET_ESID(x)             (((x) >> SID_SHIFT) & SID_MASK)
  31 
  32 /* 1T segments */
  33 #define SID_SHIFT_1T            40
  34 #define SID_MASK_1T             0xffffffUL
  35 #define ESID_MASK_1T            0xffffff0000000000UL
  36 #define GET_ESID_1T(x)          (((x) >> SID_SHIFT_1T) & SID_MASK_1T)
  37 
  38 #ifndef __ASSEMBLY__
  39 #include <asm/cache.h>
  40 
  41 typedef unsigned long pte_basic_t;
  42 
  43 static inline void clear_page(void *addr)
  44 {
  45         unsigned long iterations;
  46         unsigned long onex, twox, fourx, eightx;
  47 
  48         iterations = ppc64_caches.l1d.blocks_per_page / 8;
  49 
  50         /*
  51          * Some verisions of gcc use multiply instructions to
  52          * calculate the offsets so lets give it a hand to
  53          * do better.
  54          */
  55         onex = ppc64_caches.l1d.block_size;
  56         twox = onex << 1;
  57         fourx = onex << 2;
  58         eightx = onex << 3;
  59 
  60         asm volatile(
  61         "mtctr  %1      # clear_page\n\
  62         .balign 16\n\
  63 1:      dcbz    0,%0\n\
  64         dcbz    %3,%0\n\
  65         dcbz    %4,%0\n\
  66         dcbz    %5,%0\n\
  67         dcbz    %6,%0\n\
  68         dcbz    %7,%0\n\
  69         dcbz    %8,%0\n\
  70         dcbz    %9,%0\n\
  71         add     %0,%0,%10\n\
  72         bdnz+   1b"
  73         : "=&r" (addr)
  74         : "r" (iterations), "0" (addr), "b" (onex), "b" (twox),
  75                 "b" (twox+onex), "b" (fourx), "b" (fourx+onex),
  76                 "b" (twox+fourx), "b" (eightx-onex), "r" (eightx)
  77         : "ctr", "memory");
  78 }
  79 
  80 extern void copy_page(void *to, void *from);
  81 
  82 /* Log 2 of page table size */
  83 extern u64 ppc64_pft_size;
  84 
  85 #endif /* __ASSEMBLY__ */
  86 
  87 #define VM_DATA_DEFAULT_FLAGS \
  88         (is_32bit_task() ? \
  89          VM_DATA_DEFAULT_FLAGS32 : VM_DATA_DEFAULT_FLAGS64)
  90 
  91 /*
  92  * This is the default if a program doesn't have a PT_GNU_STACK
  93  * program header entry. The PPC64 ELF ABI has a non executable stack
  94  * stack by default, so in the absence of a PT_GNU_STACK program header
  95  * we turn execute permission off.
  96  */
  97 #define VM_STACK_DEFAULT_FLAGS32        (VM_READ | VM_WRITE | VM_EXEC | \
  98                                          VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
  99 
 100 #define VM_STACK_DEFAULT_FLAGS64        (VM_READ | VM_WRITE | \
 101                                          VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
 102 
 103 #define VM_STACK_DEFAULT_FLAGS \
 104         (is_32bit_task() ? \
 105          VM_STACK_DEFAULT_FLAGS32 : VM_STACK_DEFAULT_FLAGS64)
 106 
 107 #include <asm-generic/getorder.h>
 108 
 109 #endif /* _ASM_POWERPC_PAGE_64_H */