// SPDX-License-Identifier: GPL-2.0
/*
 * linux/arch/m68k/mm/sun3mmu.c
 *
 * Implementations of mm routines specific to the sun3 MMU.
 *
 * Moved here 8/20/1999 Sam Creasey
 *
 */

#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/memblock.h>

#include <asm/setup.h>
#include <linux/uaccess.h>
#include <asm/page.h>
#include <asm/machdep.h>
#include <asm/io.h>

#include "../sun3/sun3.h"

const char bad_pmd_string[] = "Bad pmd in pte_alloc: %08lx\n";

extern unsigned long num_pages;

/* For the sun3 we try to follow the i386 paging_init() more closely */
/* start_mem and end_mem have PAGE_OFFSET added already */
/* now sets up tables using sun3 PTEs rather than i386 as before. --m */
void __init paging_init(void)
{
        pgd_t * pg_dir;
        pte_t * pg_table;
        int i;
        unsigned long address;
        unsigned long next_pgtable;
        unsigned long bootmem_end;
        unsigned long size;

        empty_zero_page = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);

        address = PAGE_OFFSET;
        pg_dir = swapper_pg_dir;
        memset (swapper_pg_dir, 0, sizeof (swapper_pg_dir));
        memset (kernel_pg_dir,  0, sizeof (kernel_pg_dir));

        size = num_pages * sizeof(pte_t);
        size = (size + PAGE_SIZE) & ~(PAGE_SIZE-1);

        next_pgtable = (unsigned long)memblock_alloc_or_panic(size, PAGE_SIZE);
        bootmem_end = (next_pgtable + size + PAGE_SIZE) & PAGE_MASK;

        /* Map whole memory from PAGE_OFFSET (0x0E000000) */
        pg_dir += PAGE_OFFSET >> PGDIR_SHIFT;

        while (address < (unsigned long)high_memory) {
                pg_table = (pte_t *) __pa (next_pgtable);
                next_pgtable += PTRS_PER_PTE * sizeof (pte_t);
                pgd_val(*pg_dir) = (unsigned long) pg_table;
                pg_dir++;

                /* now change pg_table to kernel virtual addresses */
                pg_table = (pte_t *) __va ((unsigned long) pg_table);
                for (i=0; i<PTRS_PER_PTE; ++i, ++pg_table) {
                        pte_t pte = pfn_pte(virt_to_pfn((void *)address), PAGE_INIT);
                        if (address >= (unsigned long)high_memory)
                                pte_val (pte) = 0;
                        set_pte (pg_table, pte);
                        address += PAGE_SIZE;
                }
        }

        mmu_emu_init(bootmem_end);

        current->mm = NULL;
}

static const pgprot_t protection_map[16] = {
        [VM_NONE]                                       = PAGE_NONE,
        [VM_READ]                                       = PAGE_READONLY,
        [VM_WRITE]                                      = PAGE_COPY,
        [VM_WRITE | VM_READ]                            = PAGE_COPY,
        [VM_EXEC]                                       = PAGE_READONLY,
        [VM_EXEC | VM_READ]                             = PAGE_READONLY,
        [VM_EXEC | VM_WRITE]                            = PAGE_COPY,
        [VM_EXEC | VM_WRITE | VM_READ]                  = PAGE_COPY,
        [VM_SHARED]                                     = PAGE_NONE,
        [VM_SHARED | VM_READ]                           = PAGE_READONLY,
        [VM_SHARED | VM_WRITE]                          = PAGE_SHARED,
        [VM_SHARED | VM_WRITE | VM_READ]                = PAGE_SHARED,
        [VM_SHARED | VM_EXEC]                           = PAGE_READONLY,
        [VM_SHARED | VM_EXEC | VM_READ]                 = PAGE_READONLY,
        [VM_SHARED | VM_EXEC | VM_WRITE]                = PAGE_SHARED,
        [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]      = PAGE_SHARED
};
DECLARE_VM_GET_PAGE_PROT