qemu/include/exec/cpu-defs.h
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   1/*
   2 * common defines for all CPUs
   3 *
   4 * Copyright (c) 2003 Fabrice Bellard
   5 *
   6 * This library is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU Lesser General Public
   8 * License as published by the Free Software Foundation; either
   9 * version 2 of the License, or (at your option) any later version.
  10 *
  11 * This library is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 * Lesser General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU Lesser General Public
  17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19#ifndef CPU_DEFS_H
  20#define CPU_DEFS_H
  21
  22#ifndef NEED_CPU_H
  23#error cpu.h included from common code
  24#endif
  25
  26#include "qemu/host-utils.h"
  27#include "qemu/queue.h"
  28#ifdef CONFIG_TCG
  29#include "tcg-target.h"
  30#endif
  31#ifndef CONFIG_USER_ONLY
  32#include "exec/hwaddr.h"
  33#endif
  34#include "exec/memattrs.h"
  35
  36#ifndef TARGET_LONG_BITS
  37#error TARGET_LONG_BITS must be defined before including this header
  38#endif
  39
  40#define TARGET_LONG_SIZE (TARGET_LONG_BITS / 8)
  41
  42/* target_ulong is the type of a virtual address */
  43#if TARGET_LONG_SIZE == 4
  44typedef int32_t target_long;
  45typedef uint32_t target_ulong;
  46#define TARGET_FMT_lx "%08x"
  47#define TARGET_FMT_ld "%d"
  48#define TARGET_FMT_lu "%u"
  49#elif TARGET_LONG_SIZE == 8
  50typedef int64_t target_long;
  51typedef uint64_t target_ulong;
  52#define TARGET_FMT_lx "%016" PRIx64
  53#define TARGET_FMT_ld "%" PRId64
  54#define TARGET_FMT_lu "%" PRIu64
  55#else
  56#error TARGET_LONG_SIZE undefined
  57#endif
  58
  59#if !defined(CONFIG_USER_ONLY) && defined(CONFIG_TCG)
  60/* use a fully associative victim tlb of 8 entries */
  61#define CPU_VTLB_SIZE 8
  62
  63#if HOST_LONG_BITS == 32 && TARGET_LONG_BITS == 32
  64#define CPU_TLB_ENTRY_BITS 4
  65#else
  66#define CPU_TLB_ENTRY_BITS 5
  67#endif
  68
  69/* TCG_TARGET_TLB_DISPLACEMENT_BITS is used in CPU_TLB_BITS to ensure that
  70 * the TLB is not unnecessarily small, but still small enough for the
  71 * TLB lookup instruction sequence used by the TCG target.
  72 *
  73 * TCG will have to generate an operand as large as the distance between
  74 * env and the tlb_table[NB_MMU_MODES - 1][0].addend.  For simplicity,
  75 * the TCG targets just round everything up to the next power of two, and
  76 * count bits.  This works because: 1) the size of each TLB is a largish
  77 * power of two, 2) and because the limit of the displacement is really close
  78 * to a power of two, 3) the offset of tlb_table[0][0] inside env is smaller
  79 * than the size of a TLB.
  80 *
  81 * For example, the maximum displacement 0xFFF0 on PPC and MIPS, but TCG
  82 * just says "the displacement is 16 bits".  TCG_TARGET_TLB_DISPLACEMENT_BITS
  83 * then ensures that tlb_table at least 0x8000 bytes large ("not unnecessarily
  84 * small": 2^15).  The operand then will come up smaller than 0xFFF0 without
  85 * any particular care, because the TLB for a single MMU mode is larger than
  86 * 0x10000-0xFFF0=16 bytes.  In the end, the maximum value of the operand
  87 * could be something like 0xC000 (the offset of the last TLB table) plus
  88 * 0x18 (the offset of the addend field in each TLB entry) plus the offset
  89 * of tlb_table inside env (which is non-trivial but not huge).
  90 */
  91#define CPU_TLB_BITS                                             \
  92    MIN(8,                                                       \
  93        TCG_TARGET_TLB_DISPLACEMENT_BITS - CPU_TLB_ENTRY_BITS -  \
  94        (NB_MMU_MODES <= 1 ? 0 :                                 \
  95         NB_MMU_MODES <= 2 ? 1 :                                 \
  96         NB_MMU_MODES <= 4 ? 2 :                                 \
  97         NB_MMU_MODES <= 8 ? 3 : 4))
  98
  99#define CPU_TLB_SIZE (1 << CPU_TLB_BITS)
 100
 101typedef struct CPUTLBEntry {
 102    /* bit TARGET_LONG_BITS to TARGET_PAGE_BITS : virtual address
 103       bit TARGET_PAGE_BITS-1..4  : Nonzero for accesses that should not
 104                                    go directly to ram.
 105       bit 3                      : indicates that the entry is invalid
 106       bit 2..0                   : zero
 107    */
 108    union {
 109        struct {
 110            target_ulong addr_read;
 111            target_ulong addr_write;
 112            target_ulong addr_code;
 113            /* Addend to virtual address to get host address.  IO accesses
 114               use the corresponding iotlb value.  */
 115            uintptr_t addend;
 116        };
 117        /* padding to get a power of two size */
 118        uint8_t dummy[1 << CPU_TLB_ENTRY_BITS];
 119    };
 120} CPUTLBEntry;
 121
 122QEMU_BUILD_BUG_ON(sizeof(CPUTLBEntry) != (1 << CPU_TLB_ENTRY_BITS));
 123
 124/* The IOTLB is not accessed directly inline by generated TCG code,
 125 * so the CPUIOTLBEntry layout is not as critical as that of the
 126 * CPUTLBEntry. (This is also why we don't want to combine the two
 127 * structs into one.)
 128 */
 129typedef struct CPUIOTLBEntry {
 130    hwaddr addr;
 131    MemTxAttrs attrs;
 132} CPUIOTLBEntry;
 133
 134#ifndef NB_MEM_ATTR
 135#define NB_MEM_ATTR 2
 136#endif
 137
 138#define CPU_COMMON_TLB \
 139    /* The meaning of the MMU modes is defined in the target code. */   \
 140    CPUTLBEntry tlb_table[NB_MMU_MODES][CPU_TLB_SIZE];                  \
 141    CPUTLBEntry tlb_v_table[NB_MMU_MODES][CPU_VTLB_SIZE];               \
 142    CPUIOTLBEntry iotlb[NB_MMU_MODES][CPU_TLB_SIZE];                    \
 143    CPUIOTLBEntry iotlb_v[NB_MMU_MODES][CPU_VTLB_SIZE];                 \
 144    CPUIOTLBEntry memattr[NB_MEM_ATTR];                                 \
 145    size_t tlb_flush_count;                                             \
 146    target_ulong tlb_flush_addr;                                        \
 147    target_ulong tlb_flush_mask;                                        \
 148    target_ulong vtlb_index;                                            \
 149
 150#else
 151
 152#define CPU_COMMON_TLB
 153
 154#endif
 155
 156
 157#define CPU_COMMON                                                      \
 158    /* soft mmu support */                                              \
 159    CPU_COMMON_TLB                                                      \
 160
 161#endif
 162