Archipelago » qemu

/*

 *  Microblaze MMU emulation for qemu.

 *

 *  Copyright (c) 2009 Edgar E. Iglesias

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, see <http://www.gnu.org/licenses/>.

 */

#define MMU_R_PID    0

#define MMU_R_ZPR    1

#define MMU_R_TLBX   2

#define MMU_R_TLBLO  3

#define MMU_R_TLBHI  4

#define MMU_R_TLBSX  5

#define RAM_DATA     1

#define RAM_TAG      0

/* Tag portion */

#define TLB_EPN_MASK          0xFFFFFC00 /* Effective Page Number */

#define TLB_PAGESZ_MASK       0x00000380

#define TLB_PAGESZ(x)         (((x) & 0x7) << 7)

#define PAGESZ_1K             0

#define PAGESZ_4K             1

#define PAGESZ_16K            2

#define PAGESZ_64K            3

#define PAGESZ_256K           4

#define PAGESZ_1M             5

#define PAGESZ_4M             6

#define PAGESZ_16M            7

#define TLB_VALID             0x00000040 /* Entry is valid */

/* Data portion */

#define TLB_RPN_MASK          0xFFFFFC00 /* Real Page Number */

#define TLB_PERM_MASK         0x00000300

#define TLB_EX                0x00000200 /* Instruction execution allowed */

#define TLB_WR                0x00000100 /* Writes permitted */

#define TLB_ZSEL_MASK         0x000000F0

#define TLB_ZSEL(x)           (((x) & 0xF) << 4)

#define TLB_ATTR_MASK         0x0000000F

#define TLB_W                 0x00000008 /* Caching is write-through */

#define TLB_I                 0x00000004 /* Caching is inhibited */

#define TLB_M                 0x00000002 /* Memory is coherent */

#define TLB_G                 0x00000001 /* Memory is guarded from prefetch */

#define TLB_ENTRIES    64

struct microblaze_mmu

{

    /* Data and tag brams.  */

    uint32_t rams[2][TLB_ENTRIES];

    /* We keep a separate ram for the tids to avoid the 48 bit tag width.  */

    uint8_t tids[TLB_ENTRIES];

    /* Control flops.  */

    uint32_t regs[8];;

};

struct microblaze_mmu_lookup

{

    uint32_t paddr;

    uint32_t vaddr;

    unsigned int size;

    unsigned int idx;

    int prot;

    enum {

        ERR_PROT, ERR_MISS, ERR_HIT

    } err;

};

void mmu_flip_um(CPUState *env, unsigned int um);

unsigned int mmu_translate(struct microblaze_mmu *mmu,

                           struct microblaze_mmu_lookup *lu,

                           target_ulong vaddr, int rw, int mmu_idx);

uint32_t mmu_read(CPUState *env, uint32_t rn);

void mmu_write(CPUState *env, uint32_t rn, uint32_t v);

void mmu_init(struct microblaze_mmu *mmu);