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