/*      $NetBSD: machdep.c,v 1.256 2024/03/05 14:15:34 thorpej Exp $    */

/*
 * Copyright (c) 1988 University of Utah.
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department, The Mach Operating System project at
 * Carnegie-Mellon University and Ralph Campbell.
 *
 * 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 THE REGENTS 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.
 *
 *      @(#)machdep.c   8.3 (Berkeley) 1/12/94
 *      from: Utah Hdr: machdep.c 1.63 91/04/24
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.256 2024/03/05 14:15:34 thorpej Exp $");

#include "opt_ddb.h"
#include "opt_modular.h"
#define _PMAX_BUS_DMA_PRIVATE


#include <sys/param.h>
#include <sys/boot_flag.h>
#include <sys/buf.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/kcore.h>
#include <sys/kernel.h>
#include <sys/ksyms.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/reboot.h>
#include <sys/systm.h>
#include <sys/cpu.h>

#include <uvm/uvm_extern.h>

#include <dev/cons.h>

#include <ufs/mfs/mfs_extern.h>         /* mfs_initminiroot() */

#include <mips/cache.h>
#include <mips/locore.h>
#include <mips/regnum.h>
#include <mips/psl.h>

#include <pmax/autoconf.h>
#include <pmax/dec_prom.h>
#include <pmax/sysconf.h>
#include <pmax/bootinfo.h>

#include <pmax/pmax/machdep.h>

#if NKSYMS || defined(DDB) || defined(MODULAR)
#include <mips/db_machdep.h>
#include <ddb/db_extern.h>
#endif

#include "opt_dec_3min.h"
#include "opt_dec_maxine.h"
#include "opt_dec_3maxplus.h"
#include "ksyms.h"

unsigned int ssir;                      /* simulated interrupt register */

/* maps for VM objects */
struct vm_map *phys_map = NULL;

int             systype;                /* mother board type */
char            *bootinfo = NULL;       /* pointer to bootinfo structure */
int             cpuspeed = 30;          /* approx # instr per usec. */
intptr_t        physmem_boardmax;       /* {model,SIMM}-specific bound on physmem */
int             mem_cluster_cnt;
phys_ram_seg_t  mem_clusters[VM_PHYSSEG_MAX];

void    mach_init(int, int32_t *, int, intptr_t, u_int, char *); /* XXX */

/* Motherboard or system-specific initialization vector */
static void     unimpl_bus_reset(void);
static void     unimpl_cons_init(void);
static void     unimpl_iointr(uint32_t, vaddr_t, uint32_t);
static void     unimpl_intr_establish(device_t, void *, int,
                    int (*)(void *), void *);
static int      unimpl_memsize(void *);
static unsigned nullwork(void);

struct platform platform = {
        "iobus not set",
        unimpl_bus_reset,
        unimpl_cons_init,
        unimpl_iointr,
        unimpl_intr_establish,
        unimpl_memsize,
        (void *)nullwork,
};

extern void *esym;                      /* XXX */
extern struct consdev promcd;           /* XXX */

#define ARGV(i) ((char *)(intptr_t)(argv32[i]))

/*
 * Do all the stuff that locore normally does before calling main().
 * The first 4 arguments are passed by PROM monitor, and remaining two
 * are built on temporary stack by our boot loader (or in reg if N32/N64).
 */
void
mach_init(int argc, int32_t *argv32, int code, intptr_t cv, u_int bim, char *bip)
{
        char *cp;
        const char *bootinfo_msg;
        int i;
        char *kernend;
#if NKSYMS || defined(DDB) || defined(MODULAR)
        void *ssym = 0;
        struct btinfo_symtab *bi_syms;
#endif
        extern char edata[], end[];     /* XXX */

        /* Set up bootinfo structure looking at stack. */
        if (bim == BOOTINFO_MAGIC) {
                struct btinfo_magic *bi_magic;

                bootinfo = bip;
                bi_magic = lookup_bootinfo(BTINFO_MAGIC);
                if (bi_magic == NULL || bi_magic->magic != BOOTINFO_MAGIC)
                        bootinfo_msg =
                            "invalid magic number in bootinfo structure.\n";
                else
                        bootinfo_msg = NULL;
        }
        else
                bootinfo_msg = "invalid bootinfo pointer (old bootblocks?)\n";

        /* clear the BSS segment */
#if NKSYMS || defined(DDB) || defined(MODULAR)
        bi_syms = lookup_bootinfo(BTINFO_SYMTAB);
#ifdef EXEC_AOUT
        struct exec *aout = (struct exec *)edata;
#endif

        /* Was it a valid bootinfo symtab info? */
        if (bi_syms != NULL) {
                ssym = (void *)(intptr_t)bi_syms->ssym;
                esym = (void *)(intptr_t)bi_syms->esym;

                if (esym < (void *)end) {
                        /* protect against bogus bootinfo data */
                        kernend = end;
                } else {
                        kernend = esym;
                }
                kernend = (void *)mips_round_page(kernend);
#if 0   /* our bootloader clears BSS properly */
                memset(edata, 0, end - edata);
#endif
        } else
#ifdef EXEC_AOUT
        /* XXX: Backwards compatibility with old bootblocks - this should
         * go soon...
         */
        /* Exec header and symbols? */
        if (aout->a_midmag == 0x07018b00 && (i = aout->a_syms) != 0) {
                ssym = end;
                i += (*(long *)(end + i + 4) + 3) & ~3;         /* strings */
                esym = end + i + 4;
                kernend = (void *)mips_round_page(esym);
                memset(edata, 0, end - edata);
        } else
#endif
#endif
        {
                kernend = (void *)mips_round_page(end);
                memset(edata, 0, kernend - edata);
        }

        /* Initialize callv so we can do PROM output... */
        if (code == DEC_PROM_MAGIC) {
#ifdef _LP64
                /*
                 * Convert the call vector from using 32bit function pointers
                 * to using 64bit function pointers.
                 */
                for (i = 0; i < sizeof(callvec) / sizeof(void *); i++)
                        ((intptr_t *)&callvec)[i] = ((int32_t *)cv)[i];
                callv = &callvec;
#else
                callv = (void *)cv;
#endif
        } else {
                callv = &callvec;
        }

#ifdef DDB
        /* Make DDB "machine reset" call emulate pushing the HALT button. */
        cpu_reset_address = prom_haltbutton;
#endif

        /* Use PROM console output until we initialize a console driver. */
        cn_tab = &promcd;

#if 0
        if (bootinfo_msg != NULL)
                printf(bootinfo_msg);
#else
        __USE(bootinfo_msg);
#endif
        uvm_md_init();

        /*
         * Copy exception-dispatch code down to exception vector.
         * Initialize locore-function vector.
         * Clear out the I and D caches.
         */
        mips_vector_init(NULL, false);

        /*
         * We know the CPU type now.  Initialize our DMA tags (might
         * need this early, for certain types of console devices!!).
         */
        pmax_bus_dma_init();

        /* Check for direct boot from DS5000 REX monitor */
        if (argc > 0 && strcmp(ARGV(0), "boot") == 0) {
                argc--;
                argv32++;
        }

        /* Look at argv[0] and compute bootdev */
        makebootdev(ARGV(0));

        /*
         * Look at arguments passed to us and compute boothowto.
         */
        boothowto = RB_SINGLE;
#ifdef KADB
        boothowto |= RB_KDB;
#endif
        for (i = 1; i < argc; i++) {
                for (cp = ARGV(i); *cp; cp++) {
                        switch (*cp) {
                        case 'a': /* autoboot */
                                boothowto &= ~RB_SINGLE;
                                break;

                        case 'n': /* ask for names */
                                boothowto |= RB_ASKNAME;
                                break;

                        case 'N': /* don't ask for names */
                                boothowto &= ~RB_ASKNAME;
                                break;

                        default:
                                BOOT_FLAG(*cp, boothowto);
                                break;
                        }
                }
        }

        /*
         * Check to see if a mini-root was loaded into memory. It resides
         * at the start of the next page just after the end of BSS.
         */
        if (boothowto & RB_MINIROOT)
                kernend += round_page(mfs_initminiroot(kernend));

#if NKSYMS || defined(DDB) || defined(MODULAR)
        /* init symbols if present */
        if (esym)
                ksyms_addsyms_elf((char *)esym - (char *)ssym, ssym, esym);
#endif
#ifdef DDB
        if (boothowto & RB_KDB)
                Debugger();
#endif

        /*
         * We need to do this early for badaddr().
         */
        lwp0.l_addr = (struct user *)kernend;
        kernend += USPACE;
        mips_init_lwp0_uarea();

        /*
         * Initialize physmem_boardmax; assume no SIMM-bank limits.
         * Adjust later in model-specific code if necessary.
         */
        physmem_boardmax = MIPS_MAX_MEM_ADDR;

        /*
         * Determine what model of computer we are running on.
         */
        systype = ((prom_systype() >> 16) & 0xff);
        if (systype >= nsysinit) {
                platform_not_supported();
                /* NOTREACHED */
        }

        /* Machine specific initialization. */
        (*sysinit[systype].init)();

        /* Find out how much memory is available. */
        physmem = (*platform.memsize)(kernend);

        /*
         * Load the rest of the available pages into the VM system.
         * Put the first 8M of RAM onto a lower-priority free list, since
         * some TC boards (e.g. PixelStamp boards) are only able to DMA
         * into this region, and we want them to have a fighting chance of
         * allocating their DMA memory during autoconfiguration.
         */
        for (i = 0, physmem = 0; i < mem_cluster_cnt; ++i) {
                physmem += atop(mem_clusters[i].size);
        }

        static const struct mips_vmfreelist first8 = {
                .fl_start = 0,
                .fl_end = 8 * 1024 * 1024,
                .fl_freelist = VM_FREELIST_FIRST8
        };
        mips_page_physload(MIPS_KSEG0_START, (vaddr_t)kernend,
            mem_clusters, mem_cluster_cnt, &first8, 1);
                

        /*
         * Initialize error message buffer (at end of core).
         */
        mips_init_msgbuf();

        /*
         * Initialize the virtual memory system.
         */
        pmap_bootstrap();
}

void
mips_machdep_cache_config(void)
{
        /* All r4k pmaxen have a 1MB L2 cache. */
        if (CPUISMIPS3)
                mips_cache_info.mci_sdcache_size = 1024 * 1024;
}

void
consinit(void)
{

        (*platform.cons_init)();
}

/*
 * Machine-dependent startup code: allocate memory for variable-sized
 * tables.
 */
void
cpu_startup(void)
{
        cpu_startup_common();
}

/*
 * Look up information in bootinfo of boot loader.
 */
void *
lookup_bootinfo(int type)
{
        struct btinfo_common *bt;
        char *help = bootinfo;

        /* Check for a bootinfo record first. */
        if (help == NULL)
                return (NULL);

        do {
                bt = (struct btinfo_common *)help;
                if (bt->type == type)
                        return ((void *)help);
                help += bt->next;
        } while (bt->next != 0 &&
                (size_t)help < (size_t)bootinfo + BOOTINFO_SIZE);

        return (NULL);
}

void
cpu_reboot(int howto, char *bootstr)
{

        /* take a snap shot before clobbering any registers */
        savectx(curpcb);

#ifdef DEBUG
        if (panicstr)
                stacktrace();
#endif

        /* If system is cold, just halt. */
        if (cold) {
                howto |= RB_HALT;
                goto haltsys;
        }

        /* If "always halt" was specified as a boot flag, obey. */
        if ((boothowto & RB_HALT) != 0)
                howto |= RB_HALT;

        boothowto = howto;
        if ((howto & RB_NOSYNC) == 0) {
                /*
                 * Synchronize the disks....
                 */
                vfs_shutdown();
        }

        /* Disable interrupts. */
        splhigh();

        /* If rebooting and a dump is requested do it. */
#if 0
        if ((howto & (RB_DUMP | RB_HALT)) == RB_DUMP)
#else
        if ((howto & RB_DUMP) != 0)
#endif
                dumpsys();

haltsys:

        /* run any shutdown hooks */
        doshutdownhooks();

        pmf_system_shutdown(boothowto);

        /* Finally, halt/reboot the system. */
        printf("%s\n\n", ((howto & RB_HALT) != 0) ? "halted." : "rebooting...");
        prom_halt(howto & RB_HALT, bootstr);
        /*NOTREACHED*/
}

/*
 * Find out how much memory is available by testing memory.
 * Be careful to save and restore the original contents for msgbuf.
 */
int
memsize_scan(void *first)
{
        int i, mem;
        char *cp;

        mem = btoc((paddr_t)first - MIPS_KSEG0_START);
        cp = (char *)MIPS_PHYS_TO_KSEG1(mem << PGSHIFT);
        while (cp < (char *)physmem_boardmax) {
                int j;
                if (badaddr(cp, 4))
                        break;
                i = *(int *)cp;
                j = ((int *)cp)[4];
                *(int *)cp = 0xa5a5a5a5;
                /*
                 * Data will persist on the bus if we read it right away.
                 * Have to be tricky here.
                 */
                ((int *)cp)[4] = 0x5a5a5a5a;
                wbflush();
                if (*(int *)cp != 0xa5a5a5a5)
                        break;
                *(int *)cp = i;
                ((int *)cp)[4] = j;
                cp += PAGE_SIZE;
                mem++;
        }

        /*
         * Now that we know how much memory we have, initialize the
         * mem cluster array.
         */
        mem_clusters[0].start = 0;              /* XXX is this correct? */
        mem_clusters[0].size  = ctob(mem);
        mem_cluster_cnt = 1;

        /* clear any memory error conditions possibly caused by probe */
        (*platform.bus_reset)();
        return (mem);
}

/*
 * Find out how much memory is available by using the PROM bitmap.
 */
int
memsize_bitmap(void *first)
{
        memmap *prom_memmap = (memmap *)first;
        int i, mapbytes;
        int segstart, curaddr, xsize, segnum;

        mapbytes = prom_getbitmap(prom_memmap);
        if (mapbytes == 0)
                return (memsize_scan(first));

        segstart = curaddr = i = segnum = 0;
        xsize = prom_memmap->pagesize * 8;
        while (i < mapbytes) {
                while (i < mapbytes && prom_memmap->bitmap[i] == 0xff) {
                        ++i;
                        curaddr += xsize;
                }
                if (curaddr > segstart) {
                        mem_clusters[segnum].start = segstart;
                        mem_clusters[segnum].size = curaddr - segstart;
                        ++segnum;
                }
                while (i < mapbytes && prom_memmap->bitmap[i] != 0xff) {
                        ++i;
                        curaddr += xsize;
                }
                segstart = curaddr;
        }
        mem_cluster_cnt = segnum;
        for (i = 0; i < segnum; ++i) {
                printf("segment %2d start %08lx size %08lx\n", i,
                    (long)mem_clusters[i].start, (long)mem_clusters[i].size);
        }
        return (mapbytes * 8);
}

/*
 *  Ensure all platform vectors are always initialized.
 */
static void
unimpl_bus_reset(void)
{

        panic("sysconf.init didn't set bus_reset");
}

static void
unimpl_cons_init(void)
{

        panic("sysconf.init didn't set cons_init");
}

static void
unimpl_iointr(uint32_t status, vaddr_t pc, uint32_t ipending)
{

        panic("sysconf.init didn't set intr");
}

static void
unimpl_intr_establish(device_t dev, void *cookie, int level,
    int (*handler)(void *), void *arg)
{
        panic("sysconf.init didn't set intr_establish");
}

static int
unimpl_memsize(void *first)
{

        panic("sysconf.init didn't set memsize");
}

static unsigned
nullwork(void)
{

        return (0);
}

/*
 * Wait "n" microseconds. (scsi code needs this).
 */
void
delay(int n)
{

        DELAY(n);
}