/* $NetBSD: vmtvar.h,v 1.2 2021/03/27 21:23:14 ryo Exp $ */
/* NetBSD: vmt.c,v 1.15 2016/11/10 03:32:04 ozaki-r Exp */
/* $OpenBSD: vmt.c,v 1.11 2011/01/27 21:29:25 dtucker Exp $ */

/*
 * Copyright (c) 2007 David Crawshaw <david@zentus.com>
 * Copyright (c) 2008 David Gwynne <dlg@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef _DEV_VMT_VMTVAR_H_
#define _DEV_VMT_VMTVAR_H_

#include <sys/uuid.h>
#include <dev/sysmon/sysmonvar.h>

/* A register frame. */
/* XXX 'volatile' as a workaround because BACKDOOR_OP is likely broken */
struct vm_backdoor {
        volatile register_t eax;
        volatile register_t ebx;
        volatile register_t ecx;
        volatile register_t edx;
        volatile register_t esi;
        volatile register_t edi;
        volatile register_t ebp;
};

#define VM_REG_LOW_MASK         __BITS(15,0)
#define VM_REG_HIGH_MASK        __BITS(31,16)
#define VM_REG_WORD_MASK        __BITS(31,0)
#define VM_REG_CMD(hi, low)     \
        (__SHIFTIN((hi), VM_REG_HIGH_MASK) | __SHIFTIN((low), VM_REG_LOW_MASK))
#define VM_REG_CMD_RPC(cmd)     VM_REG_CMD((cmd), VM_CMD_RPC)
#define VM_REG_PORT_CMD(cmd)    VM_REG_CMD((cmd), VM_PORT_CMD)
#define VM_REG_PORT_RPC(cmd)    VM_REG_CMD((cmd), VM_PORT_RPC)

/* RPC context. */
struct vm_rpc {
        uint16_t channel;
        uint32_t cookie1;
        uint32_t cookie2;
};

struct vmt_event {
        struct sysmon_pswitch   ev_smpsw;
        int                     ev_code;
};

struct vmt_softc {
        device_t                sc_dev;

        struct sysctllog        *sc_log;
        struct vm_rpc           sc_tclo_rpc;
        bool                    sc_tclo_rpc_open;
        char                    *sc_rpc_buf;
        int                     sc_rpc_error;
        int                     sc_tclo_ping;
        int                     sc_set_guest_os;
#define VMT_RPC_BUFLEN                  256

        struct callout          sc_tick;
        struct callout          sc_tclo_tick;

#define VMT_CLOCK_SYNC_PERIOD_SECONDS 60
        int                     sc_clock_sync_period_seconds;
        struct callout          sc_clock_sync_tick;

        struct vmt_event        sc_ev_power;
        struct vmt_event        sc_ev_reset;
        struct vmt_event        sc_ev_sleep;
        bool                    sc_smpsw_valid;

        char                    sc_hostname[MAXHOSTNAMELEN];
        char                    sc_uuid[_UUID_STR_LEN];
};

bool vmt_probe(void);
void vmt_common_attach(struct vmt_softc *);
int vmt_common_detach(struct vmt_softc *);

#define BACKDOOR_OP_I386(op, frame)             \
        __asm__ __volatile__ (                  \
                "pushal;"                       \
                "pushl %%eax;"                  \
                "movl 0x18(%%eax), %%ebp;"      \
                "movl 0x14(%%eax), %%edi;"      \
                "movl 0x10(%%eax), %%esi;"      \
                "movl 0x0c(%%eax), %%edx;"      \
                "movl 0x08(%%eax), %%ecx;"      \
                "movl 0x04(%%eax), %%ebx;"      \
                "movl 0x00(%%eax), %%eax;"      \
                op                              \
                "xchgl %%eax, 0x00(%%esp);"     \
                "movl %%ebp, 0x18(%%eax);"      \
                "movl %%edi, 0x14(%%eax);"      \
                "movl %%esi, 0x10(%%eax);"      \
                "movl %%edx, 0x0c(%%eax);"      \
                "movl %%ecx, 0x08(%%eax);"      \
                "movl %%ebx, 0x04(%%eax);"      \
                "popl 0x00(%%eax);"             \
                "popal;"                        \
                :                               \
                :"a"(frame)                     \
        )

#define BACKDOOR_OP_AMD64(op, frame)            \
        __asm__ __volatile__ (                  \
                "pushq %%rbp;                   \n\t" \
                "pushq %%rax;                   \n\t" \
                "movq 0x30(%%rax), %%rbp;       \n\t" \
                "movq 0x28(%%rax), %%rdi;       \n\t" \
                "movq 0x20(%%rax), %%rsi;       \n\t" \
                "movq 0x18(%%rax), %%rdx;       \n\t" \
                "movq 0x10(%%rax), %%rcx;       \n\t" \
                "movq 0x08(%%rax), %%rbx;       \n\t" \
                "movq 0x00(%%rax), %%rax;       \n\t" \
                op                              "\n\t" \
                "xchgq %%rax, 0x00(%%rsp);      \n\t" \
                "movq %%rbp, 0x30(%%rax);       \n\t" \
                "movq %%rdi, 0x28(%%rax);       \n\t" \
                "movq %%rsi, 0x20(%%rax);       \n\t" \
                "movq %%rdx, 0x18(%%rax);       \n\t" \
                "movq %%rcx, 0x10(%%rax);       \n\t" \
                "movq %%rbx, 0x08(%%rax);       \n\t" \
                "popq 0x00(%%rax);              \n\t" \
                "popq %%rbp;                    \n\t" \
                : /* No outputs. */ \
                : "a" (frame) \
                  /* No pushal on amd64 so warn gcc about the clobbered registers. */\
                : "rbx", "rcx", "rdx", "rdi", "rsi", "cc", "memory" \
        )

#define X86_IO_MAGIC            0x86    /* magic for upper 32bit of x7 */
#define X86_IO_W7_SIZE_MASK     __BITS(1, 0)
#define X86_IO_W7_SIZE(n)       __SHIFTIN((n), X86_IO_W7_SIZE_MASK)
#define X86_IO_W7_DIR           __BIT(2)
#define X86_IO_W7_WITH          __BIT(3)
#define X86_IO_W7_STR           __BIT(4)
#define X86_IO_W7_DF            __BIT(5)
#define X86_IO_W7_IMM_MASK      __BITS(12, 5)
#define X86_IO_W7_IMM(imm)      __SHIFTIN((imm), X86_IO_W7_IMM_MASK)
#define BACKDOOR_OP_AARCH64(op, frame)          \
        __asm__ __volatile__ (                  \
                "ldp x0, x1, [%0, 8 * 0];       \n\t" \
                "ldp x2, x3, [%0, 8 * 2];       \n\t" \
                "ldp x4, x5, [%0, 8 * 4];       \n\t" \
                "ldr x6,     [%0, 8 * 6];       \n\t" \
                "mov x7, %1                     \n\t" \
                "movk x7, %2, lsl #32;          \n\t" \
                "mrs xzr, mdccsr_el0;           \n\t" \
                "stp x0, x1, [%0, 8 * 0];       \n\t" \
                "stp x2, x3, [%0, 8 * 2];       \n\t" \
                "stp x4, x5, [%0, 8 * 4];       \n\t" \
                "str x6,     [%0, 8 * 6];       \n\t" \
                : /* No outputs. */ \
                : "r" (frame), \
                  "r" (op), \
                  "i" (X86_IO_MAGIC) \
                : "x0", "x1", "x2", "x3", "x4", "x5", "x6", "x7", "memory" \
        )

#if defined(__i386__)
#define BACKDOOR_OP(op, frame) BACKDOOR_OP_I386(op, frame)
#elif defined(__amd64__)
#define BACKDOOR_OP(op, frame) BACKDOOR_OP_AMD64(op, frame)
#elif defined(__aarch64__)
#define BACKDOOR_OP(op, frame) BACKDOOR_OP_AARCH64(op, frame)
#endif

#if defined(__i386__) || defined(__amd64__)
#define BACKDOOR_OP_CMD "inl %%dx, %%eax;"
#define BACKDOOR_OP_IN  "cld;\n\trep insb;"
#define BACKDOOR_OP_OUT "cld;\n\trep outsb;"
#elif defined(__aarch64__)
#define BACKDOOR_OP_CMD (X86_IO_W7_WITH | X86_IO_W7_DIR | X86_IO_W7_SIZE(2))
#define BACKDOOR_OP_IN  (X86_IO_W7_WITH | X86_IO_W7_STR | X86_IO_W7_DIR)
#define BACKDOOR_OP_OUT (X86_IO_W7_WITH | X86_IO_W7_STR)
#endif

static __inline void
vmt_hvcall(uint8_t cmd, u_int regs[6])
{
        struct vm_backdoor frame;

        memset(&frame, 0, sizeof(frame));
        frame.eax = VM_MAGIC;
        frame.ebx = UINT_MAX;
        frame.ecx = VM_REG_CMD(0, cmd);
        frame.edx = VM_REG_PORT_CMD(0);

        BACKDOOR_OP(BACKDOOR_OP_CMD, &frame);

        regs[0] = __SHIFTOUT(frame.eax, VM_REG_WORD_MASK);
        regs[1] = __SHIFTOUT(frame.ebx, VM_REG_WORD_MASK);
        regs[2] = __SHIFTOUT(frame.ecx, VM_REG_WORD_MASK);
        regs[3] = __SHIFTOUT(frame.edx, VM_REG_WORD_MASK);
        regs[4] = __SHIFTOUT(frame.esi, VM_REG_WORD_MASK);
        regs[5] = __SHIFTOUT(frame.edi, VM_REG_WORD_MASK);
}

#endif /* _DEV_VMT_VMTVAR_H_ */