/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2011 NetApp, Inc.
 * All rights reserved.
 * Copyright (c) 2024 Ruslan Bukin <br@bsdpad.com>
 *
 * This software was developed by the University of Cambridge Computer
 * Laboratory (Department of Computer Science and Technology) under Innovate
 * UK project 105694, "Digital Security by Design (DSbD) Technology Platform
 * Prototype".
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/mman.h>
#include <sys/stat.h>

#include <assert.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>

#include <vmmapi.h>

#include "bhyverun.h"
#include "config.h"
#include "debug.h"
#include "fdt.h"
#include "mem.h"
#include "pci_emul.h"
#include "pci_irq.h"
#include "uart_emul.h"
#include "riscv.h"

#define FDT_SIZE        (64 * 1024)
#define FDT_DTB_ALIGN   8

/* Start of lowmem + 64K */
#define UART_MMIO_BASE  0x10000
#define UART_MMIO_SIZE  0x1000
#define UART_INTR       1

#define APLIC_MEM_BASE          0x2f000000
#define APLIC_MEM_SIZE          0x10000

#define PCIE_INTA       2
#define PCIE_INTB       3
#define PCIE_INTC       4
#define PCIE_INTD       5

void
bhyve_init_config(void)
{
        init_config();

        /* Set default values prior to option parsing. */
        set_config_bool("acpi_tables", false);
        set_config_bool("acpi_tables_in_memory", false);
        set_config_value("memory.size", "256M");
}

void
bhyve_usage(int code)
{
        const char *progname;

        progname = getprogname();

        fprintf(stderr,
            "Usage: %s [-CDHhSW]\n"
            "       %*s [-c [[cpus=]numcpus][,sockets=n][,cores=n][,threads=n]]\n"
            "       %*s [-k config_file] [-m mem] [-o var=value]\n"
            "       %*s [-p vcpu:hostcpu] [-r file] [-s pci] [-U uuid] vmname\n"
            "       -C: include guest memory in core file\n"
            "       -c: number of CPUs and/or topology specification\n"
            "       -D: destroy on power-off\n"
            "       -h: help\n"
            "       -k: key=value flat config file\n"
            "       -M: monitor mode\n"
            "       -m: memory size\n"
            "       -o: set config 'var' to 'value'\n"
            "       -p: pin 'vcpu' to 'hostcpu'\n"
            "       -S: guest memory cannot be swapped\n"
            "       -s: <slot,driver,configinfo> PCI slot config\n"
            "       -U: UUID\n"
            "       -W: force virtio to use single-vector MSI\n",
            progname, (int)strlen(progname), "", (int)strlen(progname), "",
            (int)strlen(progname), "");
        exit(code);
}

void
bhyve_optparse(int argc, char **argv)
{
        const char *optstr;
        int c;

        optstr = "hCDMSWk:f:o:p:c:s:m:U:";
        while ((c = getopt(argc, argv, optstr)) != -1) {
                switch (c) {
                case 'c':
                        if (bhyve_topology_parse(optarg) != 0) {
                                errx(EX_USAGE, "invalid cpu topology '%s'",
                                    optarg);
                        }
                        break;
                case 'C':
                        set_config_bool("memory.guest_in_core", true);
                        break;
                case 'D':
                        set_config_bool("destroy_on_poweroff", true);
                        break;
                case 'k':
                        bhyve_parse_simple_config_file(optarg);
                        break;
                case 'M':
                        set_config_bool("monitor", true);
                        break;
                case 'm':
                        set_config_value("memory.size", optarg);
                        break;
                case 'o':
                        if (!bhyve_parse_config_option(optarg)) {
                                errx(EX_USAGE,
                                    "invalid configuration option '%s'",
                                    optarg);
                        }
                        break;
                case 'p':
                        if (bhyve_pincpu_parse(optarg) != 0) {
                                errx(EX_USAGE,
                                    "invalid vcpu pinning configuration '%s'",
                                    optarg);
                        }
                        break;
                case 's':
                        if (strncmp(optarg, "help", strlen(optarg)) == 0) {
                                pci_print_supported_devices();
                                exit(0);
                        } else if (pci_parse_slot(optarg) != 0)
                                exit(BHYVE_EXIT_ERROR);
                        else
                                break;
                case 'S':
                        set_config_bool("memory.wired", true);
                        break;
                case 'U':
                        set_config_value("uuid", optarg);
                        break;
                case 'W':
                        set_config_bool("virtio_msix", false);
                        break;
                case 'h':
                        bhyve_usage(0);
                default:
                        bhyve_usage(1);
                }
        }
}

void
bhyve_init_vcpu(struct vcpu *vcpu __unused)
{
}

void
bhyve_start_vcpu(struct vcpu *vcpu, bool bsp __unused)
{
        int error;

        /* Set hart ID. */
        error = vm_set_register(vcpu, VM_REG_GUEST_A0, vcpu_id(vcpu));
        assert(error == 0);

        fbsdrun_addcpu(vcpu_id(vcpu));
}

/*
 * Load the specified boot code at the beginning of high memory.
 */
static void
load_bootrom(struct vmctx *ctx, const char *path, uint64_t *elrp,
    uint64_t *lenp)
{
        struct stat sb;
        void *data, *gptr;
        vm_paddr_t loadaddr;
        off_t size;
        int fd;

        fd = open(path, O_RDONLY);
        if (fd < 0)
                err(1, "open(%s)", path);
        if (fstat(fd, &sb) != 0)
                err(1, "fstat(%s)", path);

        size = sb.st_size;

        loadaddr = vm_get_highmem_base(ctx);
        gptr = vm_map_gpa(ctx, loadaddr, round_page(size));

        data = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
        if (data == MAP_FAILED)
                err(1, "mmap(%s)", path);
        (void)close(fd);
        memcpy(gptr, data, size);

        if (munmap(data, size) != 0)
                err(1, "munmap(%s)", path);

        *elrp = loadaddr;
        *lenp = size;
}

static void
mmio_uart_intr_assert(void *arg)
{
        struct vmctx *ctx = arg;

        vm_assert_irq(ctx, UART_INTR);
}

static void
mmio_uart_intr_deassert(void *arg)
{
        struct vmctx *ctx = arg;

        vm_deassert_irq(ctx, UART_INTR);
}

static int
mmio_uart_mem_handler(struct vcpu *vcpu __unused, int dir, uint64_t addr,
    int size __unused, uint64_t *val, void *arg1, long arg2)
{
        struct uart_ns16550_softc *sc = arg1;
        long reg;

        reg = addr - arg2;
        if (dir == MEM_F_WRITE)
                uart_ns16550_write(sc, reg, *val);
        else
                *val = uart_ns16550_read(sc, reg);

        return (0);
}

static bool
init_mmio_uart(struct vmctx *ctx)
{
        struct uart_ns16550_softc *sc;
        struct mem_range mr;
        const char *path;
        int error;

        path = get_config_value("console");
        if (path == NULL)
                return (false);

        sc = uart_ns16550_init(mmio_uart_intr_assert, mmio_uart_intr_deassert,
            ctx);
        if (uart_ns16550_tty_open(sc, path) != 0) {
                EPRINTLN("Unable to initialize backend '%s' for mmio uart",
                    path);
                assert(0);
        }

        bzero(&mr, sizeof(struct mem_range));
        mr.name = "uart";
        mr.base = UART_MMIO_BASE;
        mr.size = UART_MMIO_SIZE;
        mr.flags = MEM_F_RW;
        mr.handler = mmio_uart_mem_handler;
        mr.arg1 = sc;
        mr.arg2 = mr.base;
        error = register_mem(&mr);
        assert(error == 0);

        return (true);
}

int
bhyve_init_platform(struct vmctx *ctx, struct vcpu *bsp)
{
        const char *bootrom;
        uint64_t elr;
        uint64_t len;
        int error;
        int pcie_intrs[4] = {PCIE_INTA, PCIE_INTB, PCIE_INTC, PCIE_INTD};
        vm_paddr_t fdt_gpa;
        char isa[32];
        int retval;

        bootrom = get_config_value("bootrom");
        if (bootrom == NULL) {
                warnx("no bootrom specified");
                return (ENOENT);
        }
        load_bootrom(ctx, bootrom, &elr, &len);
        error = vm_set_register(bsp, VM_REG_GUEST_SEPC, elr);
        if (error != 0) {
                warn("vm_set_register(GUEST_SEPC)");
                return (error);
        }

        error = vm_get_capability(bsp, VM_CAP_SSTC, &retval);
        assert(error == 0);
        snprintf(isa, sizeof(isa), "%s%s", "rv64imafdc",
            retval == 1 ? "_sstc" : "");

        fdt_gpa = vm_get_highmem_base(ctx) + roundup2(len, FDT_DTB_ALIGN);
        error = fdt_init(ctx, guest_ncpus, fdt_gpa, FDT_SIZE, isa);
        if (error != 0)
                return (error);

        /* Set FDT base address to the bootable hart. */
        error = vm_set_register(bsp, VM_REG_GUEST_A1, fdt_gpa);
        assert(error == 0);

        fdt_add_aplic(APLIC_MEM_BASE, APLIC_MEM_SIZE, guest_ncpus);
        error = vm_attach_aplic(ctx, APLIC_MEM_BASE, APLIC_MEM_SIZE);
        if (error != 0) {
                warn("vm_attach_aplic()");
                return (error);
        }

        if (init_mmio_uart(ctx))
                fdt_add_uart(UART_MMIO_BASE, UART_MMIO_SIZE, UART_INTR);

        pci_irq_init(pcie_intrs);
        fdt_add_pcie(pcie_intrs);
        vmexit_set_bsp(vcpu_id(bsp));

        return (0);
}

int
bhyve_init_platform_late(struct vmctx *ctx __unused, struct vcpu *bsp __unused)
{

        fdt_finalize();

        return (0);
}