root/arch/m68k/kernel/setup_mm.c
// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/arch/m68k/kernel/setup.c
 *
 *  Copyright (C) 1995  Hamish Macdonald
 */

/*
 * This file handles the architecture-dependent parts of system setup
 */

#include <linux/kernel.h>
#include <linux/cpu.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/console.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/memblock.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/module.h>
#include <linux/nvram.h>
#include <linux/initrd.h>
#include <linux/random.h>

#include <asm/bootinfo.h>
#include <asm/byteorder.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/fpu.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/machdep.h>
#ifdef CONFIG_AMIGA
#include <asm/amigahw.h>
#endif
#include <asm/atarihw.h>
#ifdef CONFIG_ATARI
#include <asm/atari_stram.h>
#endif
#ifdef CONFIG_SUN3X
#include <asm/dvma.h>
#endif
#include <asm/macintosh.h>
#include <asm/natfeat.h>
#include <asm/config.h>

#if !FPSTATESIZE || !NR_IRQS
#warning No CPU/platform type selected, your kernel will not work!
#warning Are you building an allnoconfig kernel?
#endif

unsigned long m68k_machtype;
EXPORT_SYMBOL(m68k_machtype);
unsigned long m68k_cputype;
EXPORT_SYMBOL(m68k_cputype);
unsigned long m68k_fputype;
unsigned long m68k_mmutype;
EXPORT_SYMBOL(m68k_mmutype);
#ifdef CONFIG_VME
unsigned long vme_brdtype;
EXPORT_SYMBOL(vme_brdtype);
#endif

int m68k_is040or060;
EXPORT_SYMBOL(m68k_is040or060);

extern unsigned long availmem;

int m68k_num_memory;
EXPORT_SYMBOL(m68k_num_memory);
int m68k_realnum_memory;
EXPORT_SYMBOL(m68k_realnum_memory);
unsigned long m68k_memoffset;
struct m68k_mem_info m68k_memory[NUM_MEMINFO];
EXPORT_SYMBOL(m68k_memory);

static struct m68k_mem_info m68k_ramdisk __initdata;

static char m68k_command_line[CL_SIZE] __initdata;

void (*mach_sched_init) (void) __initdata = NULL;
/* machine dependent irq functions */
void (*mach_init_IRQ) (void) __initdata = NULL;
void (*mach_get_model) (char *model);
void (*mach_get_hardware_list) (struct seq_file *m);
void (*mach_reset)( void );
void (*mach_halt)( void );
#ifdef CONFIG_HEARTBEAT
void (*mach_heartbeat) (int);
EXPORT_SYMBOL(mach_heartbeat);
#endif
#ifdef CONFIG_M68K_L2_CACHE
void (*mach_l2_flush) (int);
#endif
#if defined(CONFIG_ISA) && defined(MULTI_ISA)
int isa_type;
int isa_sex;
EXPORT_SYMBOL(isa_type);
EXPORT_SYMBOL(isa_sex);
#endif

#define MASK_256K 0xfffc0000

static void __init m68k_parse_bootinfo(const struct bi_record *record)
{
        const struct bi_record *first_record = record;
        uint16_t tag;

        while ((tag = be16_to_cpu(record->tag)) != BI_LAST) {
                int unknown = 0;
                const void *data = record->data;
                uint16_t size = be16_to_cpu(record->size);

                switch (tag) {
                case BI_MACHTYPE:
                case BI_CPUTYPE:
                case BI_FPUTYPE:
                case BI_MMUTYPE:
                        /* Already set up by head.S */
                        break;

                case BI_MEMCHUNK:
                        if (m68k_num_memory < NUM_MEMINFO) {
                                const struct mem_info *m = data;
                                m68k_memory[m68k_num_memory].addr =
                                        be32_to_cpu(m->addr);
                                m68k_memory[m68k_num_memory].size =
                                        be32_to_cpu(m->size);
                                m68k_num_memory++;
                        } else
                                pr_warn("%s: too many memory chunks\n",
                                        __func__);
                        break;

                case BI_RAMDISK:
                        {
                                const struct mem_info *m = data;
                                m68k_ramdisk.addr = be32_to_cpu(m->addr);
                                m68k_ramdisk.size = be32_to_cpu(m->size);
                        }
                        break;

                case BI_COMMAND_LINE:
                        strscpy(m68k_command_line, data);
                        break;

                case BI_RNG_SEED: {
                        u16 len = be16_to_cpup(data);
                        add_bootloader_randomness(data + 2, len);
                        /*
                         * Zero the data to preserve forward secrecy, and zero the
                         * length to prevent kexec from using it.
                         */
                        memzero_explicit((void *)data, len + 2);
                        break;
                }

                default:
                        if (MACH_IS_AMIGA)
                                unknown = amiga_parse_bootinfo(record);
                        else if (MACH_IS_ATARI)
                                unknown = atari_parse_bootinfo(record);
                        else if (MACH_IS_MAC)
                                unknown = mac_parse_bootinfo(record);
                        else if (MACH_IS_Q40)
                                unknown = q40_parse_bootinfo(record);
                        else if (MACH_IS_BVME6000)
                                unknown = bvme6000_parse_bootinfo(record);
                        else if (MACH_IS_MVME16x)
                                unknown = mvme16x_parse_bootinfo(record);
                        else if (MACH_IS_MVME147)
                                unknown = mvme147_parse_bootinfo(record);
                        else if (MACH_IS_HP300)
                                unknown = hp300_parse_bootinfo(record);
                        else if (MACH_IS_APOLLO)
                                unknown = apollo_parse_bootinfo(record);
                        else if (MACH_IS_VIRT)
                                unknown = virt_parse_bootinfo(record);
                        else
                                unknown = 1;
                }
                if (unknown)
                        pr_warn("%s: unknown tag 0x%04x ignored\n", __func__,
                                tag);
                record = (struct bi_record *)((unsigned long)record + size);
        }

        save_bootinfo(first_record);

        m68k_realnum_memory = m68k_num_memory;
#ifdef CONFIG_SINGLE_MEMORY_CHUNK
        if (m68k_num_memory > 1) {
                pr_warn("%s: ignoring last %i chunks of physical memory\n",
                        __func__, (m68k_num_memory - 1));
                m68k_num_memory = 1;
        }
#endif
}

void __init setup_arch(char **cmdline_p)
{
        /* The bootinfo is located right after the kernel */
        if (!CPU_IS_COLDFIRE)
                m68k_parse_bootinfo((const struct bi_record *)_end);

        if (CPU_IS_040)
                m68k_is040or060 = 4;
        else if (CPU_IS_060)
                m68k_is040or060 = 6;

        /* FIXME: m68k_fputype is passed in by Penguin booter, which can
         * be confused by software FPU emulation. BEWARE.
         * We should really do our own FPU check at startup.
         * [what do we do with buggy 68LC040s? if we have problems
         *  with them, we should add a test to check_bugs() below] */
#if defined(CONFIG_FPU) && !defined(CONFIG_M68KFPU_EMU_ONLY)
        /* clear the fpu if we have one */
        if (m68k_fputype & (FPU_68881|FPU_68882|FPU_68040|FPU_68060|FPU_COLDFIRE)) {
                volatile int zero = 0;
                asm volatile ("frestore %0" : : "m" (zero));
        }
#endif

        if (CPU_IS_060) {
                u32 pcr;

                asm (".chip 68060; movec %%pcr,%0; .chip 68k"
                     : "=d" (pcr));
                if (((pcr >> 8) & 0xff) <= 5) {
                        pr_warn("Enabling workaround for errata I14\n");
                        asm (".chip 68060; movec %0,%%pcr; .chip 68k"
                             : : "d" (pcr | 0x20));
                }
        }

        setup_initial_init_mm((void *)PAGE_OFFSET, _etext, _edata, _end);

#if defined(CONFIG_BOOTPARAM)
        strscpy(m68k_command_line, CONFIG_BOOTPARAM_STRING, CL_SIZE);
#endif /* CONFIG_BOOTPARAM */
        process_uboot_commandline(&m68k_command_line[0], CL_SIZE);
        *cmdline_p = m68k_command_line;
        memcpy(boot_command_line, *cmdline_p, CL_SIZE);
        /*
         * Initialise the static keys early as they may be enabled by the
         * cpufeature code and early parameters.
         */
        jump_label_init();
        parse_early_param();

        switch (m68k_machtype) {
#ifdef CONFIG_AMIGA
        case MACH_AMIGA:
                config_amiga();
                break;
#endif
#ifdef CONFIG_ATARI
        case MACH_ATARI:
                config_atari();
                break;
#endif
#ifdef CONFIG_MAC
        case MACH_MAC:
                config_mac();
                break;
#endif
#ifdef CONFIG_SUN3
        case MACH_SUN3:
                config_sun3();
                break;
#endif
#ifdef CONFIG_APOLLO
        case MACH_APOLLO:
                config_apollo();
                break;
#endif
#ifdef CONFIG_MVME147
        case MACH_MVME147:
                config_mvme147();
                break;
#endif
#ifdef CONFIG_MVME16x
        case MACH_MVME16x:
                config_mvme16x();
                break;
#endif
#ifdef CONFIG_BVME6000
        case MACH_BVME6000:
                config_bvme6000();
                break;
#endif
#ifdef CONFIG_HP300
        case MACH_HP300:
                config_hp300();
                break;
#endif
#ifdef CONFIG_Q40
        case MACH_Q40:
                config_q40();
                break;
#endif
#ifdef CONFIG_SUN3X
        case MACH_SUN3X:
                config_sun3x();
                break;
#endif
#ifdef CONFIG_COLDFIRE
        case MACH_M54XX:
        case MACH_M5441X:
                cf_bootmem_alloc();
                cf_mmu_context_init();
                config_BSP(NULL, 0);
                break;
#endif
#ifdef CONFIG_VIRT
        case MACH_VIRT:
                config_virt();
                break;
#endif
        default:
                panic("No configuration setup");
        }

        if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && m68k_ramdisk.size)
                memblock_reserve(m68k_ramdisk.addr, m68k_ramdisk.size);

        paging_init();

        if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && m68k_ramdisk.size) {
                initrd_start = (unsigned long)phys_to_virt(m68k_ramdisk.addr);
                initrd_end = initrd_start + m68k_ramdisk.size;
                pr_info("initrd: %08lx - %08lx\n", initrd_start, initrd_end);
        }

#ifdef CONFIG_NATFEAT
        nf_init();
#endif

#ifdef CONFIG_ATARI
        if (MACH_IS_ATARI)
                atari_stram_reserve_pages((void *)availmem);
#endif
#ifdef CONFIG_SUN3X
        if (MACH_IS_SUN3X) {
                dvma_init();
        }
#endif

/* set ISA defs early as possible */
#if defined(CONFIG_ISA) && defined(MULTI_ISA)
        if (MACH_IS_Q40) {
                isa_type = ISA_TYPE_Q40;
                isa_sex = 0;
        }
#ifdef CONFIG_AMIGA_PCMCIA
        if (MACH_IS_AMIGA && AMIGAHW_PRESENT(PCMCIA)) {
                isa_type = ISA_TYPE_AG;
                isa_sex = 1;
        }
#endif
#ifdef CONFIG_ATARI_ROM_ISA
        if (MACH_IS_ATARI) {
                isa_type = ISA_TYPE_ENEC;
                isa_sex = 0;
        }
#endif
#endif
}

static int show_cpuinfo(struct seq_file *m, void *v)
{
        const char *cpu, *mmu, *fpu;
        unsigned long clockfreq, clockfactor;

#define LOOP_CYCLES_68020       (8)
#define LOOP_CYCLES_68030       (8)
#define LOOP_CYCLES_68040       (3)
#define LOOP_CYCLES_68060       (1)
#define LOOP_CYCLES_COLDFIRE    (2)

        if (CPU_IS_020) {
                cpu = "68020";
                clockfactor = LOOP_CYCLES_68020;
        } else if (CPU_IS_030) {
                cpu = "68030";
                clockfactor = LOOP_CYCLES_68030;
        } else if (CPU_IS_040) {
                cpu = "68040";
                clockfactor = LOOP_CYCLES_68040;
        } else if (CPU_IS_060) {
                cpu = "68060";
                clockfactor = LOOP_CYCLES_68060;
        } else if (CPU_IS_COLDFIRE) {
                cpu = "ColdFire";
                clockfactor = LOOP_CYCLES_COLDFIRE;
        } else {
                cpu = "680x0";
                clockfactor = 0;
        }

#ifdef CONFIG_M68KFPU_EMU_ONLY
        fpu = "none(soft float)";
#else
        if (m68k_fputype & FPU_68881)
                fpu = "68881";
        else if (m68k_fputype & FPU_68882)
                fpu = "68882";
        else if (m68k_fputype & FPU_68040)
                fpu = "68040";
        else if (m68k_fputype & FPU_68060)
                fpu = "68060";
        else if (m68k_fputype & FPU_SUNFPA)
                fpu = "Sun FPA";
        else if (m68k_fputype & FPU_COLDFIRE)
                fpu = "ColdFire";
        else
                fpu = "none";
#endif

        if (m68k_mmutype & MMU_68851)
                mmu = "68851";
        else if (m68k_mmutype & MMU_68030)
                mmu = "68030";
        else if (m68k_mmutype & MMU_68040)
                mmu = "68040";
        else if (m68k_mmutype & MMU_68060)
                mmu = "68060";
        else if (m68k_mmutype & MMU_SUN3)
                mmu = "Sun-3";
        else if (m68k_mmutype & MMU_APOLLO)
                mmu = "Apollo";
        else if (m68k_mmutype & MMU_COLDFIRE)
                mmu = "ColdFire";
        else
                mmu = "unknown";

        clockfreq = loops_per_jiffy * HZ * clockfactor;

        seq_printf(m, "CPU:\t\t%s\n"
                   "MMU:\t\t%s\n"
                   "FPU:\t\t%s\n"
                   "Clocking:\t%lu.%1luMHz\n"
                   "BogoMips:\t%lu.%02lu\n"
                   "Calibration:\t%lu loops\n",
                   cpu, mmu, fpu,
                   clockfreq/1000000,(clockfreq/100000)%10,
                   loops_per_jiffy/(500000/HZ),(loops_per_jiffy/(5000/HZ))%100,
                   loops_per_jiffy);
        return 0;
}

static void *c_start(struct seq_file *m, loff_t *pos)
{
        return *pos < 1 ? (void *)1 : NULL;
}
static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
        ++*pos;
        return NULL;
}
static void c_stop(struct seq_file *m, void *v)
{
}
const struct seq_operations cpuinfo_op = {
        .start  = c_start,
        .next   = c_next,
        .stop   = c_stop,
        .show   = show_cpuinfo,
};

#ifdef CONFIG_PROC_HARDWARE
static int hardware_proc_show(struct seq_file *m, void *v)
{
        char model[80];
        unsigned long mem;
        int i;

        if (mach_get_model)
                mach_get_model(model);
        else
                strscpy(model, "Unknown m68k");

        seq_printf(m, "Model:\t\t%s\n", model);
        for (mem = 0, i = 0; i < m68k_num_memory; i++)
                mem += m68k_memory[i].size;
        seq_printf(m, "System Memory:\t%ldK\n", mem >> 10);

        if (mach_get_hardware_list)
                mach_get_hardware_list(m);

        return 0;
}

static int __init proc_hardware_init(void)
{
        proc_create_single("hardware", 0, NULL, hardware_proc_show);
        return 0;
}
module_init(proc_hardware_init);
#endif

void __init arch_cpu_finalize_init(void)
{
#if defined(CONFIG_FPU) && !defined(CONFIG_M68KFPU_EMU)
        if (m68k_fputype == 0) {
                pr_emerg("*** YOU DO NOT HAVE A FLOATING POINT UNIT, "
                        "WHICH IS REQUIRED BY LINUX/M68K ***\n");
                pr_emerg("Upgrade your hardware or join the FPU "
                        "emulation project\n");
                panic("no FPU");
        }
#endif /* !CONFIG_M68KFPU_EMU */
}

#ifdef CONFIG_ADB
static int __init adb_probe_sync_enable (char *str) {
        extern int __adb_probe_sync;
        __adb_probe_sync = 1;
        return 1;
}

__setup("adb_sync", adb_probe_sync_enable);
#endif /* CONFIG_ADB */

#if IS_ENABLED(CONFIG_NVRAM)
#ifdef CONFIG_MAC
static unsigned char m68k_nvram_read_byte(int addr)
{
        if (MACH_IS_MAC)
                return mac_pram_read_byte(addr);
        return 0xff;
}

static void m68k_nvram_write_byte(unsigned char val, int addr)
{
        if (MACH_IS_MAC)
                mac_pram_write_byte(val, addr);
}
#endif /* CONFIG_MAC */

#ifdef CONFIG_ATARI
static ssize_t m68k_nvram_read(char *buf, size_t count, loff_t *ppos)
{
        if (MACH_IS_ATARI)
                return atari_nvram_read(buf, count, ppos);
        else if (MACH_IS_MAC)
                return nvram_read_bytes(buf, count, ppos);
        return -EINVAL;
}

static ssize_t m68k_nvram_write(char *buf, size_t count, loff_t *ppos)
{
        if (MACH_IS_ATARI)
                return atari_nvram_write(buf, count, ppos);
        else if (MACH_IS_MAC)
                return nvram_write_bytes(buf, count, ppos);
        return -EINVAL;
}

static long m68k_nvram_set_checksum(void)
{
        if (MACH_IS_ATARI)
                return atari_nvram_set_checksum();
        return -EINVAL;
}

static long m68k_nvram_initialize(void)
{
        if (MACH_IS_ATARI)
                return atari_nvram_initialize();
        return -EINVAL;
}
#endif /* CONFIG_ATARI */

static ssize_t m68k_nvram_get_size(void)
{
        if (MACH_IS_ATARI)
                return atari_nvram_get_size();
        else if (MACH_IS_MAC)
                return mac_pram_get_size();
        return -ENODEV;
}

/* Atari device drivers call .read (to get checksum validation) whereas
 * Mac and PowerMac device drivers just use .read_byte.
 */
const struct nvram_ops arch_nvram_ops = {
#ifdef CONFIG_MAC
        .read_byte      = m68k_nvram_read_byte,
        .write_byte     = m68k_nvram_write_byte,
#endif
#ifdef CONFIG_ATARI
        .read           = m68k_nvram_read,
        .write          = m68k_nvram_write,
        .set_checksum   = m68k_nvram_set_checksum,
        .initialize     = m68k_nvram_initialize,
#endif
        .get_size       = m68k_nvram_get_size,
};
EXPORT_SYMBOL(arch_nvram_ops);
#endif /* CONFIG_NVRAM */