/*
 *  Alpha emulation cpu definitions for qemu.
 *
 *  Copyright (c) 2007 Jocelyn Mayer
 *
 * 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/>.
 */

#ifndef ALPHA_CPU_H
#define ALPHA_CPU_H

#include "qemu-common.h"
#include "cpu-qom.h"

#define TARGET_LONG_BITS 64
#define ALIGNED_ONLY

#define CPUArchState struct CPUAlphaState

/* Alpha processors have a weak memory model */
#define TCG_GUEST_DEFAULT_MO      (0)

#include "exec/cpu-defs.h"

#define ICACHE_LINE_SIZE 32
#define DCACHE_LINE_SIZE 32

#define TARGET_PAGE_BITS 13

#ifdef CONFIG_USER_ONLY
/* ??? The kernel likes to give addresses in high memory.  If the host has
   more virtual address space than the guest, this can lead to impossible
   allocations.  Honor the long-standing assumption that only kernel addrs
   are negative, but otherwise allow allocations anywhere.  This could lead
   to tricky emulation problems for programs doing tagged addressing, but
   that's far fewer than encounter the impossible allocation problem.  */
#define TARGET_PHYS_ADDR_SPACE_BITS  63
#define TARGET_VIRT_ADDR_SPACE_BITS  63
#else
/* ??? EV4 has 34 phys addr bits, EV5 has 40, EV6 has 44.  */
#define TARGET_PHYS_ADDR_SPACE_BITS  44
#define TARGET_VIRT_ADDR_SPACE_BITS  (30 + TARGET_PAGE_BITS)
#endif

/* Alpha major type */
enum {
    ALPHA_EV3  = 1,
    ALPHA_EV4  = 2,
    ALPHA_SIM  = 3,
    ALPHA_LCA  = 4,
    ALPHA_EV5  = 5, /* 21164 */
    ALPHA_EV45 = 6, /* 21064A */
    ALPHA_EV56 = 7, /* 21164A */
};

/* EV4 minor type */
enum {
    ALPHA_EV4_2 = 0,
    ALPHA_EV4_3 = 1,
};

/* LCA minor type */
enum {
    ALPHA_LCA_1 = 1, /* 21066 */
    ALPHA_LCA_2 = 2, /* 20166 */
    ALPHA_LCA_3 = 3, /* 21068 */
    ALPHA_LCA_4 = 4, /* 21068 */
    ALPHA_LCA_5 = 5, /* 21066A */
    ALPHA_LCA_6 = 6, /* 21068A */
};

/* EV5 minor type */
enum {
    ALPHA_EV5_1 = 1, /* Rev BA, CA */
    ALPHA_EV5_2 = 2, /* Rev DA, EA */
    ALPHA_EV5_3 = 3, /* Pass 3 */
    ALPHA_EV5_4 = 4, /* Pass 3.2 */
    ALPHA_EV5_5 = 5, /* Pass 4 */
};

/* EV45 minor type */
enum {
    ALPHA_EV45_1 = 1, /* Pass 1 */
    ALPHA_EV45_2 = 2, /* Pass 1.1 */
    ALPHA_EV45_3 = 3, /* Pass 2 */
};

/* EV56 minor type */
enum {
    ALPHA_EV56_1 = 1, /* Pass 1 */
    ALPHA_EV56_2 = 2, /* Pass 2 */
};

enum {
    IMPLVER_2106x = 0, /* EV4, EV45 & LCA45 */
    IMPLVER_21164 = 1, /* EV5, EV56 & PCA45 */
    IMPLVER_21264 = 2, /* EV6, EV67 & EV68x */
    IMPLVER_21364 = 3, /* EV7 & EV79 */
};

enum {
    AMASK_BWX      = 0x00000001,
    AMASK_FIX      = 0x00000002,
    AMASK_CIX      = 0x00000004,
    AMASK_MVI      = 0x00000100,
    AMASK_TRAP     = 0x00000200,
    AMASK_PREFETCH = 0x00001000,
};

enum {
    VAX_ROUND_NORMAL = 0,
    VAX_ROUND_CHOPPED,
};

enum {
    IEEE_ROUND_NORMAL = 0,
    IEEE_ROUND_DYNAMIC,
    IEEE_ROUND_PLUS,
    IEEE_ROUND_MINUS,
    IEEE_ROUND_CHOPPED,
};

/* IEEE floating-point operations encoding */
/* Trap mode */
enum {
    FP_TRAP_I   = 0x0,
    FP_TRAP_U   = 0x1,
    FP_TRAP_S  = 0x4,
    FP_TRAP_SU  = 0x5,
    FP_TRAP_SUI = 0x7,
};

/* Rounding mode */
enum {
    FP_ROUND_CHOPPED = 0x0,
    FP_ROUND_MINUS   = 0x1,
    FP_ROUND_NORMAL  = 0x2,
    FP_ROUND_DYNAMIC = 0x3,
};

/* FPCR bits -- right-shifted 32 so we can use a uint32_t.  */
#define FPCR_SUM                (1U << (63 - 32))
#define FPCR_INED               (1U << (62 - 32))
#define FPCR_UNFD               (1U << (61 - 32))
#define FPCR_UNDZ               (1U << (60 - 32))
#define FPCR_DYN_SHIFT          (58 - 32)
#define FPCR_DYN_CHOPPED        (0U << FPCR_DYN_SHIFT)
#define FPCR_DYN_MINUS          (1U << FPCR_DYN_SHIFT)
#define FPCR_DYN_NORMAL         (2U << FPCR_DYN_SHIFT)
#define FPCR_DYN_PLUS           (3U << FPCR_DYN_SHIFT)
#define FPCR_DYN_MASK           (3U << FPCR_DYN_SHIFT)
#define FPCR_IOV                (1U << (57 - 32))
#define FPCR_INE                (1U << (56 - 32))
#define FPCR_UNF                (1U << (55 - 32))
#define FPCR_OVF                (1U << (54 - 32))
#define FPCR_DZE                (1U << (53 - 32))
#define FPCR_INV                (1U << (52 - 32))
#define FPCR_OVFD               (1U << (51 - 32))
#define FPCR_DZED               (1U << (50 - 32))
#define FPCR_INVD               (1U << (49 - 32))
#define FPCR_DNZ                (1U << (48 - 32))
#define FPCR_DNOD               (1U << (47 - 32))
#define FPCR_STATUS_MASK        (FPCR_IOV | FPCR_INE | FPCR_UNF \
                                 | FPCR_OVF | FPCR_DZE | FPCR_INV)

/* The silly software trap enables implemented by the kernel emulation.
   These are more or less architecturally required, since the real hardware
   has read-as-zero bits in the FPCR when the features aren't implemented.
   For the purposes of QEMU, we pretend the FPCR can hold everything.  */
#define SWCR_TRAP_ENABLE_INV    (1U << 1)
#define SWCR_TRAP_ENABLE_DZE    (1U << 2)
#define SWCR_TRAP_ENABLE_OVF    (1U << 3)
#define SWCR_TRAP_ENABLE_UNF    (1U << 4)
#define SWCR_TRAP_ENABLE_INE    (1U << 5)
#define SWCR_TRAP_ENABLE_DNO    (1U << 6)
#define SWCR_TRAP_ENABLE_MASK   ((1U << 7) - (1U << 1))

#define SWCR_MAP_DMZ            (1U << 12)
#define SWCR_MAP_UMZ            (1U << 13)
#define SWCR_MAP_MASK           (SWCR_MAP_DMZ | SWCR_MAP_UMZ)

#define SWCR_STATUS_INV         (1U << 17)
#define SWCR_STATUS_DZE         (1U << 18)
#define SWCR_STATUS_OVF         (1U << 19)
#define SWCR_STATUS_UNF         (1U << 20)
#define SWCR_STATUS_INE         (1U << 21)
#define SWCR_STATUS_DNO         (1U << 22)
#define SWCR_STATUS_MASK        ((1U << 23) - (1U << 17))

#define SWCR_STATUS_TO_EXCSUM_SHIFT  16

#define SWCR_MASK  (SWCR_TRAP_ENABLE_MASK | SWCR_MAP_MASK | SWCR_STATUS_MASK)

/* MMU modes definitions */

/* Alpha has 5 MMU modes: PALcode, Kernel, Executive, Supervisor, and User.
   The Unix PALcode only exposes the kernel and user modes; presumably
   executive and supervisor are used by VMS.

   PALcode itself uses physical mode for code and kernel mode for data;
   there are PALmode instructions that can access data via physical mode
   or via an os-installed "alternate mode", which is one of the 4 above.

   That said, we're only emulating Unix PALcode, and not attempting VMS,
   so we don't need to implement Executive and Supervisor.  QEMU's own
   PALcode cheats and usees the KSEG mapping for its code+data rather than
   physical addresses.  */

#define NB_MMU_MODES 3

#define MMU_MODE0_SUFFIX _kernel
#define MMU_MODE1_SUFFIX _user
#define MMU_KERNEL_IDX   0
#define MMU_USER_IDX     1
#define MMU_PHYS_IDX     2

typedef struct CPUAlphaState CPUAlphaState;

struct CPUAlphaState {
    uint64_t ir[31];
    float64 fir[31];
    uint64_t pc;
    uint64_t unique;
    uint64_t lock_addr;
    uint64_t lock_value;

    /* The FPCR, and disassembled portions thereof.  */
    uint32_t fpcr;
#ifdef CONFIG_USER_ONLY
    uint32_t swcr;
#endif
    uint32_t fpcr_exc_enable;
    float_status fp_status;
    uint8_t fpcr_dyn_round;
    uint8_t fpcr_flush_to_zero;

    /* Mask of PALmode, Processor State et al.  Most of this gets copied
       into the TranslatorBlock flags and controls code generation.  */
    uint32_t flags;

    /* The high 32-bits of the processor cycle counter.  */
    uint32_t pcc_ofs;

    /* These pass data from the exception logic in the translator and
       helpers to the OS entry point.  This is used for both system
       emulation and user-mode.  */
    uint64_t trap_arg0;
    uint64_t trap_arg1;
    uint64_t trap_arg2;

#if !defined(CONFIG_USER_ONLY)
    /* The internal data required by our emulation of the Unix PALcode.  */
    uint64_t exc_addr;
    uint64_t palbr;
    uint64_t ptbr;
    uint64_t vptptr;
    uint64_t sysval;
    uint64_t usp;
    uint64_t shadow[8];
    uint64_t scratch[24];
#endif

    /* This alarm doesn't exist in real hardware; we wish it did.  */
    uint64_t alarm_expire;

    /* Those resources are used only in QEMU core */
    CPU_COMMON

    int error_code;

    uint32_t features;
    uint32_t amask;
    int implver;
};

/**
 * AlphaCPU:
 * @env: #CPUAlphaState
 *
 * An Alpha CPU.
 */
struct AlphaCPU {
    /*< private >*/
    CPUState parent_obj;
    /*< public >*/

    CPUAlphaState env;

    /* This alarm doesn't exist in real hardware; we wish it did.  */
    QEMUTimer *alarm_timer;
};

static inline AlphaCPU *alpha_env_get_cpu(CPUAlphaState *env)
{
    return container_of(env, AlphaCPU, env);
}

#define ENV_GET_CPU(e) CPU(alpha_env_get_cpu(e))

#define ENV_OFFSET offsetof(AlphaCPU, env)

#ifndef CONFIG_USER_ONLY
extern const struct VMStateDescription vmstate_alpha_cpu;
#endif

void alpha_cpu_do_interrupt(CPUState *cpu);
bool alpha_cpu_exec_interrupt(CPUState *cpu, int int_req);
void alpha_cpu_dump_state(CPUState *cs, FILE *f, int flags);
hwaddr alpha_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
int alpha_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
int alpha_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
void alpha_cpu_do_unaligned_access(CPUState *cpu, vaddr addr,
                                   MMUAccessType access_type,
                                   int mmu_idx, uintptr_t retaddr);

#define cpu_list alpha_cpu_list
#define cpu_signal_handler cpu_alpha_signal_handler

#include "exec/cpu-all.h"

enum {
    FEATURE_ASN    = 0x00000001,
    FEATURE_SPS    = 0x00000002,
    FEATURE_VIRBND = 0x00000004,
    FEATURE_TBCHK  = 0x00000008,
};

enum {
    EXCP_RESET,
    EXCP_MCHK,
    EXCP_SMP_INTERRUPT,
    EXCP_CLK_INTERRUPT,
    EXCP_DEV_INTERRUPT,
    EXCP_MMFAULT,
    EXCP_UNALIGN,
    EXCP_OPCDEC,
    EXCP_ARITH,
    EXCP_FEN,
    EXCP_CALL_PAL,
};

/* Alpha-specific interrupt pending bits.  */
#define CPU_INTERRUPT_TIMER	CPU_INTERRUPT_TGT_EXT_0
#define CPU_INTERRUPT_SMP	CPU_INTERRUPT_TGT_EXT_1
#define CPU_INTERRUPT_MCHK	CPU_INTERRUPT_TGT_EXT_2

/* OSF/1 Page table bits.  */
enum {
    PTE_VALID = 0x0001,
    PTE_FOR   = 0x0002,  /* used for page protection (fault on read) */
    PTE_FOW   = 0x0004,  /* used for page protection (fault on write) */
    PTE_FOE   = 0x0008,  /* used for page protection (fault on exec) */
    PTE_ASM   = 0x0010,
    PTE_KRE   = 0x0100,
    PTE_URE   = 0x0200,
    PTE_KWE   = 0x1000,
    PTE_UWE   = 0x2000
};

/* Hardware interrupt (entInt) constants.  */
enum {
    INT_K_IP,
    INT_K_CLK,
    INT_K_MCHK,
    INT_K_DEV,
    INT_K_PERF,
};

/* Memory management (entMM) constants.  */
enum {
    MM_K_TNV,
    MM_K_ACV,
    MM_K_FOR,
    MM_K_FOE,
    MM_K_FOW
};

/* Arithmetic exception (entArith) constants.  */
enum {
    EXC_M_SWC = 1,      /* Software completion */
    EXC_M_INV = 2,      /* Invalid operation */
    EXC_M_DZE = 4,      /* Division by zero */
    EXC_M_FOV = 8,      /* Overflow */
    EXC_M_UNF = 16,     /* Underflow */
    EXC_M_INE = 32,     /* Inexact result */
    EXC_M_IOV = 64      /* Integer Overflow */
};

/* Processor status constants.  */
/* Low 3 bits are interrupt mask level.  */
#define PS_INT_MASK   7u

/* Bits 4 and 5 are the mmu mode.  The VMS PALcode uses all 4 modes;
   The Unix PALcode only uses bit 4.  */
#define PS_USER_MODE  8u

/* CPUAlphaState->flags constants.  These are layed out so that we
   can set or reset the pieces individually by assigning to the byte,
   or manipulated as a whole.  */

#define ENV_FLAG_PAL_SHIFT    0
#define ENV_FLAG_PS_SHIFT     8
#define ENV_FLAG_RX_SHIFT     16
#define ENV_FLAG_FEN_SHIFT    24

#define ENV_FLAG_PAL_MODE     (1u << ENV_FLAG_PAL_SHIFT)
#define ENV_FLAG_PS_USER      (PS_USER_MODE << ENV_FLAG_PS_SHIFT)
#define ENV_FLAG_RX_FLAG      (1u << ENV_FLAG_RX_SHIFT)
#define ENV_FLAG_FEN          (1u << ENV_FLAG_FEN_SHIFT)

#define ENV_FLAG_TB_MASK \
    (ENV_FLAG_PAL_MODE | ENV_FLAG_PS_USER | ENV_FLAG_FEN)

static inline int cpu_mmu_index(CPUAlphaState *env, bool ifetch)
{
    int ret = env->flags & ENV_FLAG_PS_USER ? MMU_USER_IDX : MMU_KERNEL_IDX;
    if (env->flags & ENV_FLAG_PAL_MODE) {
        ret = MMU_KERNEL_IDX;
    }
    return ret;
}

enum {
    IR_V0   = 0,
    IR_T0   = 1,
    IR_T1   = 2,
    IR_T2   = 3,
    IR_T3   = 4,
    IR_T4   = 5,
    IR_T5   = 6,
    IR_T6   = 7,
    IR_T7   = 8,
    IR_S0   = 9,
    IR_S1   = 10,
    IR_S2   = 11,
    IR_S3   = 12,
    IR_S4   = 13,
    IR_S5   = 14,
    IR_S6   = 15,
    IR_FP   = IR_S6,
    IR_A0   = 16,
    IR_A1   = 17,
    IR_A2   = 18,
    IR_A3   = 19,
    IR_A4   = 20,
    IR_A5   = 21,
    IR_T8   = 22,
    IR_T9   = 23,
    IR_T10  = 24,
    IR_T11  = 25,
    IR_RA   = 26,
    IR_T12  = 27,
    IR_PV   = IR_T12,
    IR_AT   = 28,
    IR_GP   = 29,
    IR_SP   = 30,
    IR_ZERO = 31,
};

void alpha_translate_init(void);

#define ALPHA_CPU_TYPE_SUFFIX "-" TYPE_ALPHA_CPU
#define ALPHA_CPU_TYPE_NAME(model) model ALPHA_CPU_TYPE_SUFFIX
#define CPU_RESOLVING_TYPE TYPE_ALPHA_CPU

void alpha_cpu_list(void);
/* you can call this signal handler from your SIGBUS and SIGSEGV
   signal handlers to inform the virtual CPU of exceptions. non zero
   is returned if the signal was handled by the virtual CPU.  */
int cpu_alpha_signal_handler(int host_signum, void *pinfo,
                             void *puc);
bool alpha_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
                        MMUAccessType access_type, int mmu_idx,
                        bool probe, uintptr_t retaddr);
void QEMU_NORETURN dynamic_excp(CPUAlphaState *, uintptr_t, int, int);
void QEMU_NORETURN arith_excp(CPUAlphaState *, uintptr_t, int, uint64_t);

uint64_t cpu_alpha_load_fpcr (CPUAlphaState *env);
void cpu_alpha_store_fpcr (CPUAlphaState *env, uint64_t val);
uint64_t cpu_alpha_load_gr(CPUAlphaState *env, unsigned reg);
void cpu_alpha_store_gr(CPUAlphaState *env, unsigned reg, uint64_t val);
#ifndef CONFIG_USER_ONLY
void alpha_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
                                     vaddr addr, unsigned size,
                                     MMUAccessType access_type,
                                     int mmu_idx, MemTxAttrs attrs,
                                     MemTxResult response, uintptr_t retaddr);
#endif

static inline void cpu_get_tb_cpu_state(CPUAlphaState *env, target_ulong *pc,
                                        target_ulong *cs_base, uint32_t *pflags)
{
    *pc = env->pc;
    *cs_base = 0;
    *pflags = env->flags & ENV_FLAG_TB_MASK;
}

#ifdef CONFIG_USER_ONLY
/* Copied from linux ieee_swcr_to_fpcr.  */
static inline uint64_t alpha_ieee_swcr_to_fpcr(uint64_t swcr)
{
    uint64_t fpcr = 0;

    fpcr |= (swcr & SWCR_STATUS_MASK) << 35;
    fpcr |= (swcr & SWCR_MAP_DMZ) << 36;
    fpcr |= (~swcr & (SWCR_TRAP_ENABLE_INV
                      | SWCR_TRAP_ENABLE_DZE
                      | SWCR_TRAP_ENABLE_OVF)) << 48;
    fpcr |= (~swcr & (SWCR_TRAP_ENABLE_UNF
                      | SWCR_TRAP_ENABLE_INE)) << 57;
    fpcr |= (swcr & SWCR_MAP_UMZ ? FPCR_UNDZ | FPCR_UNFD : 0);
    fpcr |= (~swcr & SWCR_TRAP_ENABLE_DNO) << 41;

    return fpcr;
}

/* Copied from linux ieee_fpcr_to_swcr.  */
static inline uint64_t alpha_ieee_fpcr_to_swcr(uint64_t fpcr)
{
    uint64_t swcr = 0;

    swcr |= (fpcr >> 35) & SWCR_STATUS_MASK;
    swcr |= (fpcr >> 36) & SWCR_MAP_DMZ;
    swcr |= (~fpcr >> 48) & (SWCR_TRAP_ENABLE_INV
                             | SWCR_TRAP_ENABLE_DZE
                             | SWCR_TRAP_ENABLE_OVF);
    swcr |= (~fpcr >> 57) & (SWCR_TRAP_ENABLE_UNF | SWCR_TRAP_ENABLE_INE);
    swcr |= (fpcr >> 47) & SWCR_MAP_UMZ;
    swcr |= (~fpcr >> 41) & SWCR_TRAP_ENABLE_DNO;

    return swcr;
}
#endif /* CONFIG_USER_ONLY */

#endif /* ALPHA_CPU_H */