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cpu-defs.h (8550B)


      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 2.1 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/thread.h"
     28 #ifndef CONFIG_USER_ONLY
     29 #include "exec/hwaddr.h"
     30 #endif
     31 #include "exec/memattrs.h"
     32 #include "hw/core/cpu.h"
     33 
     34 #include "cpu-param.h"
     35 
     36 #ifndef TARGET_LONG_BITS
     37 # error TARGET_LONG_BITS must be defined in cpu-param.h
     38 #endif
     39 #ifndef NB_MMU_MODES
     40 # error NB_MMU_MODES must be defined in cpu-param.h
     41 #endif
     42 #ifndef TARGET_PHYS_ADDR_SPACE_BITS
     43 # error TARGET_PHYS_ADDR_SPACE_BITS must be defined in cpu-param.h
     44 #endif
     45 #ifndef TARGET_VIRT_ADDR_SPACE_BITS
     46 # error TARGET_VIRT_ADDR_SPACE_BITS must be defined in cpu-param.h
     47 #endif
     48 #ifndef TARGET_PAGE_BITS
     49 # ifdef TARGET_PAGE_BITS_VARY
     50 #  ifndef TARGET_PAGE_BITS_MIN
     51 #   error TARGET_PAGE_BITS_MIN must be defined in cpu-param.h
     52 #  endif
     53 # else
     54 #  error TARGET_PAGE_BITS must be defined in cpu-param.h
     55 # endif
     56 #endif
     57 #ifndef TARGET_TB_PCREL
     58 # define TARGET_TB_PCREL 0
     59 #endif
     60 
     61 #define TARGET_LONG_SIZE (TARGET_LONG_BITS / 8)
     62 
     63 /* target_ulong is the type of a virtual address */
     64 #if TARGET_LONG_SIZE == 4
     65 typedef int32_t target_long;
     66 typedef uint32_t target_ulong;
     67 #define TARGET_FMT_lx "%08x"
     68 #define TARGET_FMT_ld "%d"
     69 #define TARGET_FMT_lu "%u"
     70 #elif TARGET_LONG_SIZE == 8
     71 typedef int64_t target_long;
     72 typedef uint64_t target_ulong;
     73 #define TARGET_FMT_lx "%016" PRIx64
     74 #define TARGET_FMT_ld "%" PRId64
     75 #define TARGET_FMT_lu "%" PRIu64
     76 #else
     77 #error TARGET_LONG_SIZE undefined
     78 #endif
     79 
     80 #if !defined(CONFIG_USER_ONLY) && defined(CONFIG_TCG)
     81 
     82 /* use a fully associative victim tlb of 8 entries */
     83 #define CPU_VTLB_SIZE 8
     84 
     85 #if HOST_LONG_BITS == 32 && TARGET_LONG_BITS == 32
     86 #define CPU_TLB_ENTRY_BITS 4
     87 #else
     88 #define CPU_TLB_ENTRY_BITS 5
     89 #endif
     90 
     91 #define CPU_TLB_DYN_MIN_BITS 6
     92 #define CPU_TLB_DYN_DEFAULT_BITS 8
     93 
     94 # if HOST_LONG_BITS == 32
     95 /* Make sure we do not require a double-word shift for the TLB load */
     96 #  define CPU_TLB_DYN_MAX_BITS (32 - TARGET_PAGE_BITS)
     97 # else /* HOST_LONG_BITS == 64 */
     98 /*
     99  * Assuming TARGET_PAGE_BITS==12, with 2**22 entries we can cover 2**(22+12) ==
    100  * 2**34 == 16G of address space. This is roughly what one would expect a
    101  * TLB to cover in a modern (as of 2018) x86_64 CPU. For instance, Intel
    102  * Skylake's Level-2 STLB has 16 1G entries.
    103  * Also, make sure we do not size the TLB past the guest's address space.
    104  */
    105 #  ifdef TARGET_PAGE_BITS_VARY
    106 #   define CPU_TLB_DYN_MAX_BITS                                  \
    107     MIN(22, TARGET_VIRT_ADDR_SPACE_BITS - TARGET_PAGE_BITS)
    108 #  else
    109 #   define CPU_TLB_DYN_MAX_BITS                                  \
    110     MIN_CONST(22, TARGET_VIRT_ADDR_SPACE_BITS - TARGET_PAGE_BITS)
    111 #  endif
    112 # endif
    113 
    114 /* Minimalized TLB entry for use by TCG fast path. */
    115 typedef struct CPUTLBEntry {
    116     /* bit TARGET_LONG_BITS to TARGET_PAGE_BITS : virtual address
    117        bit TARGET_PAGE_BITS-1..4  : Nonzero for accesses that should not
    118                                     go directly to ram.
    119        bit 3                      : indicates that the entry is invalid
    120        bit 2..0                   : zero
    121     */
    122     union {
    123         struct {
    124             target_ulong addr_read;
    125             target_ulong addr_write;
    126             target_ulong addr_code;
    127             /* Addend to virtual address to get host address.  IO accesses
    128                use the corresponding iotlb value.  */
    129             uintptr_t addend;
    130         };
    131         /* padding to get a power of two size */
    132         uint8_t dummy[1 << CPU_TLB_ENTRY_BITS];
    133     };
    134 } CPUTLBEntry;
    135 
    136 QEMU_BUILD_BUG_ON(sizeof(CPUTLBEntry) != (1 << CPU_TLB_ENTRY_BITS));
    137 
    138 /*
    139  * The full TLB entry, which is not accessed by generated TCG code,
    140  * so the layout is not as critical as that of CPUTLBEntry. This is
    141  * also why we don't want to combine the two structs.
    142  */
    143 typedef struct CPUTLBEntryFull {
    144     /*
    145      * @xlat_section contains:
    146      *  - in the lower TARGET_PAGE_BITS, a physical section number
    147      *  - with the lower TARGET_PAGE_BITS masked off, an offset which
    148      *    must be added to the virtual address to obtain:
    149      *     + the ram_addr_t of the target RAM (if the physical section
    150      *       number is PHYS_SECTION_NOTDIRTY or PHYS_SECTION_ROM)
    151      *     + the offset within the target MemoryRegion (otherwise)
    152      */
    153     hwaddr xlat_section;
    154 
    155     /*
    156      * @phys_addr contains the physical address in the address space
    157      * given by cpu_asidx_from_attrs(cpu, @attrs).
    158      */
    159     hwaddr phys_addr;
    160 
    161     /* @attrs contains the memory transaction attributes for the page. */
    162     MemTxAttrs attrs;
    163 
    164     /* @prot contains the complete protections for the page. */
    165     uint8_t prot;
    166 
    167     /* @lg_page_size contains the log2 of the page size. */
    168     uint8_t lg_page_size;
    169 
    170     /*
    171      * Allow target-specific additions to this structure.
    172      * This may be used to cache items from the guest cpu
    173      * page tables for later use by the implementation.
    174      */
    175 #ifdef TARGET_PAGE_ENTRY_EXTRA
    176     TARGET_PAGE_ENTRY_EXTRA
    177 #endif
    178 } CPUTLBEntryFull;
    179 
    180 /*
    181  * Data elements that are per MMU mode, minus the bits accessed by
    182  * the TCG fast path.
    183  */
    184 typedef struct CPUTLBDesc {
    185     /*
    186      * Describe a region covering all of the large pages allocated
    187      * into the tlb.  When any page within this region is flushed,
    188      * we must flush the entire tlb.  The region is matched if
    189      * (addr & large_page_mask) == large_page_addr.
    190      */
    191     target_ulong large_page_addr;
    192     target_ulong large_page_mask;
    193     /* host time (in ns) at the beginning of the time window */
    194     int64_t window_begin_ns;
    195     /* maximum number of entries observed in the window */
    196     size_t window_max_entries;
    197     size_t n_used_entries;
    198     /* The next index to use in the tlb victim table.  */
    199     size_t vindex;
    200     /* The tlb victim table, in two parts.  */
    201     CPUTLBEntry vtable[CPU_VTLB_SIZE];
    202     CPUTLBEntryFull vfulltlb[CPU_VTLB_SIZE];
    203     CPUTLBEntryFull *fulltlb;
    204 } CPUTLBDesc;
    205 
    206 /*
    207  * Data elements that are per MMU mode, accessed by the fast path.
    208  * The structure is aligned to aid loading the pair with one insn.
    209  */
    210 typedef struct CPUTLBDescFast {
    211     /* Contains (n_entries - 1) << CPU_TLB_ENTRY_BITS */
    212     uintptr_t mask;
    213     /* The array of tlb entries itself. */
    214     CPUTLBEntry *table;
    215 } CPUTLBDescFast QEMU_ALIGNED(2 * sizeof(void *));
    216 
    217 /*
    218  * Data elements that are shared between all MMU modes.
    219  */
    220 typedef struct CPUTLBCommon {
    221     /* Serialize updates to f.table and d.vtable, and others as noted. */
    222     QemuSpin lock;
    223     /*
    224      * Within dirty, for each bit N, modifications have been made to
    225      * mmu_idx N since the last time that mmu_idx was flushed.
    226      * Protected by tlb_c.lock.
    227      */
    228     uint16_t dirty;
    229     /*
    230      * Statistics.  These are not lock protected, but are read and
    231      * written atomically.  This allows the monitor to print a snapshot
    232      * of the stats without interfering with the cpu.
    233      */
    234     size_t full_flush_count;
    235     size_t part_flush_count;
    236     size_t elide_flush_count;
    237 } CPUTLBCommon;
    238 
    239 /*
    240  * The entire softmmu tlb, for all MMU modes.
    241  * The meaning of each of the MMU modes is defined in the target code.
    242  * Since this is placed within CPUNegativeOffsetState, the smallest
    243  * negative offsets are at the end of the struct.
    244  */
    245 
    246 typedef struct CPUTLB {
    247     CPUTLBCommon c;
    248     CPUTLBDesc d[NB_MMU_MODES];
    249     CPUTLBDescFast f[NB_MMU_MODES];
    250 } CPUTLB;
    251 
    252 /* This will be used by TCG backends to compute offsets.  */
    253 #define TLB_MASK_TABLE_OFS(IDX) \
    254     ((int)offsetof(ArchCPU, neg.tlb.f[IDX]) - (int)offsetof(ArchCPU, env))
    255 
    256 #else
    257 
    258 typedef struct CPUTLB { } CPUTLB;
    259 
    260 #endif  /* !CONFIG_USER_ONLY && CONFIG_TCG */
    261 
    262 /*
    263  * This structure must be placed in ArchCPU immediately
    264  * before CPUArchState, as a field named "neg".
    265  */
    266 typedef struct CPUNegativeOffsetState {
    267     CPUTLB tlb;
    268     IcountDecr icount_decr;
    269 } CPUNegativeOffsetState;
    270 
    271 #endif