[people/ms/linux.git] / arch / m68k / mm / motorola.c

// SPDX-License-Identifier: GPL-2.0
/*
 * linux/arch/m68k/mm/motorola.c
 *
 * Routines specific to the Motorola MMU, originally from:
 * linux/arch/m68k/init.c
 * which are Copyright (C) 1995 Hamish Macdonald
 *
 * Moved 8/20/1999 Sam Creasey
 */

#include <linux/module.h>
#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 <linux/gfp.h>

#include <asm/setup.h>
#include <linux/uaccess.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/machdep.h>
#include <asm/io.h>
#ifdef CONFIG_ATARI
#include <asm/atari_stram.h>
#endif
#include <asm/sections.h>

#undef DEBUG

#ifndef mm_cachebits
/*
 * Bits to add to page descriptors for "normal" caching mode.
 * For 68020/030 this is 0.
 * For 68040, this is _PAGE_CACHE040 (cachable, copyback)
 */
unsigned long mm_cachebits;
EXPORT_SYMBOL(mm_cachebits);
#endif

/* Prior to calling these routines, the page should have been flushed
 * from both the cache and ATC, or the CPU might not notice that the
 * cache setting for the page has been changed. -jskov
 */
static inline void nocache_page(void *vaddr)
{
	unsigned long addr = (unsigned long)vaddr;

	if (CPU_IS_040_OR_060) {
		pte_t *ptep = virt_to_kpte(addr);

		*ptep = pte_mknocache(*ptep);
	}
}

static inline void cache_page(void *vaddr)
{
	unsigned long addr = (unsigned long)vaddr;

	if (CPU_IS_040_OR_060) {
		pte_t *ptep = virt_to_kpte(addr);

		*ptep = pte_mkcache(*ptep);
	}
}

/*
 * Motorola 680x0 user's manual recommends using uncached memory for address
 * translation tables.
 *
 * Seeing how the MMU can be external on (some of) these chips, that seems like
 * a very important recommendation to follow. Provide some helpers to combat
 * 'variation' amongst the users of this.
 */

void mmu_page_ctor(void *page)
{
	__flush_page_to_ram(page);
	flush_tlb_kernel_page(page);
	nocache_page(page);
}

void mmu_page_dtor(void *page)
{
	cache_page(page);
}

/* ++andreas: {get,free}_pointer_table rewritten to use unused fields from
   struct page instead of separately kmalloced struct.  Stolen from
   arch/sparc/mm/srmmu.c ... */

typedef struct list_head ptable_desc;

static struct list_head ptable_list[2] = {
	LIST_HEAD_INIT(ptable_list[0]),
	LIST_HEAD_INIT(ptable_list[1]),
};

#define PD_PTABLE(page) ((ptable_desc *)&(virt_to_page(page)->lru))
#define PD_PAGE(ptable) (list_entry(ptable, struct page, lru))
#define PD_MARKBITS(dp) (*(unsigned int *)&PD_PAGE(dp)->index)

static const int ptable_shift[2] = {
	7+2, /* PGD, PMD */
	6+2, /* PTE */
};

#define ptable_size(type) (1U << ptable_shift[type])
#define ptable_mask(type) ((1U << (PAGE_SIZE / ptable_size(type))) - 1)

void __init init_pointer_table(void *table, int type)
{
	ptable_desc *dp;
	unsigned long ptable = (unsigned long)table;
	unsigned long page = ptable & PAGE_MASK;
	unsigned int mask = 1U << ((ptable - page)/ptable_size(type));

	dp = PD_PTABLE(page);
	if (!(PD_MARKBITS(dp) & mask)) {
		PD_MARKBITS(dp) = ptable_mask(type);
		list_add(dp, &ptable_list[type]);
	}

	PD_MARKBITS(dp) &= ~mask;
	pr_debug("init_pointer_table: %lx, %x\n", ptable, PD_MARKBITS(dp));

	/* unreserve the page so it's possible to free that page */
	__ClearPageReserved(PD_PAGE(dp));
	init_page_count(PD_PAGE(dp));

	return;
}

void *get_pointer_table(int type)
{
	ptable_desc *dp = ptable_list[type].next;
	unsigned int mask = list_empty(&ptable_list[type]) ? 0 : PD_MARKBITS(dp);
	unsigned int tmp, off;

	/*
	 * For a pointer table for a user process address space, a
	 * table is taken from a page allocated for the purpose.  Each
	 * page can hold 8 pointer tables.  The page is remapped in
	 * virtual address space to be noncacheable.
	 */
	if (mask == 0) {
		void *page;
		ptable_desc *new;

		if (!(page = (void *)get_zeroed_page(GFP_KERNEL)))
			return NULL;

		if (type == TABLE_PTE) {
			/*
			 * m68k doesn't have SPLIT_PTE_PTLOCKS for not having
			 * SMP.
			 */
			pgtable_pte_page_ctor(virt_to_page(page));
		}

		mmu_page_ctor(page);

		new = PD_PTABLE(page);
		PD_MARKBITS(new) = ptable_mask(type) - 1;
		list_add_tail(new, dp);

		return (pmd_t *)page;
	}

	for (tmp = 1, off = 0; (mask & tmp) == 0; tmp <<= 1, off += ptable_size(type))
		;
	PD_MARKBITS(dp) = mask & ~tmp;
	if (!PD_MARKBITS(dp)) {
		/* move to end of list */
		list_move_tail(dp, &ptable_list[type]);
	}
	return page_address(PD_PAGE(dp)) + off;
}

int free_pointer_table(void *table, int type)
{
	ptable_desc *dp;
	unsigned long ptable = (unsigned long)table;
	unsigned long page = ptable & PAGE_MASK;
	unsigned int mask = 1U << ((ptable - page)/ptable_size(type));

	dp = PD_PTABLE(page);
	if (PD_MARKBITS (dp) & mask)
		panic ("table already free!");

	PD_MARKBITS (dp) |= mask;

	if (PD_MARKBITS(dp) == ptable_mask(type)) {
		/* all tables in page are free, free page */
		list_del(dp);
		mmu_page_dtor((void *)page);
		if (type == TABLE_PTE)
			pgtable_pte_page_dtor(virt_to_page(page));
		free_page (page);
		return 1;
	} else if (ptable_list[type].next != dp) {
		/*
		 * move this descriptor to the front of the list, since
		 * it has one or more free tables.
		 */
		list_move(dp, &ptable_list[type]);
	}
	return 0;
}

/* size of memory already mapped in head.S */
extern __initdata unsigned long m68k_init_mapped_size;

extern unsigned long availmem;

static pte_t *last_pte_table __initdata = NULL;

static pte_t * __init kernel_page_table(void)
{
	pte_t *pte_table = last_pte_table;

	if (PAGE_ALIGNED(last_pte_table)) {
		pte_table = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
		if (!pte_table) {
			panic("%s: Failed to allocate %lu bytes align=%lx\n",
					__func__, PAGE_SIZE, PAGE_SIZE);
		}

		clear_page(pte_table);
		mmu_page_ctor(pte_table);

		last_pte_table = pte_table;
	}

	last_pte_table += PTRS_PER_PTE;

	return pte_table;
}

static pmd_t *last_pmd_table __initdata = NULL;

static pmd_t * __init kernel_ptr_table(void)
{
	if (!last_pmd_table) {
		unsigned long pmd, last;
		int i;

		/* Find the last ptr table that was used in head.S and
		 * reuse the remaining space in that page for further
		 * ptr tables.
		 */
		last = (unsigned long)kernel_pg_dir;
		for (i = 0; i < PTRS_PER_PGD; i++) {
			pud_t *pud = (pud_t *)(&kernel_pg_dir[i]);

			if (!pud_present(*pud))
				continue;
			pmd = pgd_page_vaddr(kernel_pg_dir[i]);
			if (pmd > last)
				last = pmd;
		}

		last_pmd_table = (pmd_t *)last;
#ifdef DEBUG
		printk("kernel_ptr_init: %p\n", last_pmd_table);
#endif
	}

	last_pmd_table += PTRS_PER_PMD;
	if (PAGE_ALIGNED(last_pmd_table)) {
		last_pmd_table = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
		if (!last_pmd_table)
			panic("%s: Failed to allocate %lu bytes align=%lx\n",
			      __func__, PAGE_SIZE, PAGE_SIZE);

		clear_page(last_pmd_table);
		mmu_page_ctor(last_pmd_table);
	}

	return last_pmd_table;
}

static void __init map_node(int node)
{
	unsigned long physaddr, virtaddr, size;
	pgd_t *pgd_dir;
	p4d_t *p4d_dir;
	pud_t *pud_dir;
	pmd_t *pmd_dir;
	pte_t *pte_dir;

	size = m68k_memory[node].size;
	physaddr = m68k_memory[node].addr;
	virtaddr = (unsigned long)phys_to_virt(physaddr);
	physaddr |= m68k_supervisor_cachemode |
		    _PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY;
	if (CPU_IS_040_OR_060)
		physaddr |= _PAGE_GLOBAL040;

	while (size > 0) {
#ifdef DEBUG
		if (!(virtaddr & (PMD_SIZE-1)))
			printk ("\npa=%#lx va=%#lx ", physaddr & PAGE_MASK,
				virtaddr);
#endif
		pgd_dir = pgd_offset_k(virtaddr);
		if (virtaddr && CPU_IS_020_OR_030) {
			if (!(virtaddr & (PGDIR_SIZE-1)) &&
			    size >= PGDIR_SIZE) {
#ifdef DEBUG
				printk ("[very early term]");
#endif
				pgd_val(*pgd_dir) = physaddr;
				size -= PGDIR_SIZE;
				virtaddr += PGDIR_SIZE;
				physaddr += PGDIR_SIZE;
				continue;
			}
		}
		p4d_dir = p4d_offset(pgd_dir, virtaddr);
		pud_dir = pud_offset(p4d_dir, virtaddr);
		if (!pud_present(*pud_dir)) {
			pmd_dir = kernel_ptr_table();
#ifdef DEBUG
			printk ("[new pointer %p]", pmd_dir);
#endif
			pud_set(pud_dir, pmd_dir);
		} else
			pmd_dir = pmd_offset(pud_dir, virtaddr);

		if (CPU_IS_020_OR_030) {
			if (virtaddr) {
#ifdef DEBUG
				printk ("[early term]");
#endif
				pmd_val(*pmd_dir) = physaddr;
				physaddr += PMD_SIZE;
			} else {
				int i;
#ifdef DEBUG
				printk ("[zero map]");
#endif
				pte_dir = kernel_page_table();
				pmd_set(pmd_dir, pte_dir);

				pte_val(*pte_dir++) = 0;
				physaddr += PAGE_SIZE;
				for (i = 1; i < PTRS_PER_PTE; physaddr += PAGE_SIZE, i++)
					pte_val(*pte_dir++) = physaddr;
			}
			size -= PMD_SIZE;
			virtaddr += PMD_SIZE;
		} else {
			if (!pmd_present(*pmd_dir)) {
#ifdef DEBUG
				printk ("[new table]");
#endif
				pte_dir = kernel_page_table();
				pmd_set(pmd_dir, pte_dir);
			}
			pte_dir = pte_offset_kernel(pmd_dir, virtaddr);

			if (virtaddr) {
				if (!pte_present(*pte_dir))
					pte_val(*pte_dir) = physaddr;
			} else
				pte_val(*pte_dir) = 0;
			size -= PAGE_SIZE;
			virtaddr += PAGE_SIZE;
			physaddr += PAGE_SIZE;
		}

	}
#ifdef DEBUG
	printk("\n");
#endif
}

/*
 * paging_init() continues the virtual memory environment setup which
 * was begun by the code in arch/head.S.
 */
void __init paging_init(void)
{
	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
	unsigned long min_addr, max_addr;
	unsigned long addr;
	int i;

#ifdef DEBUG
	printk ("start of paging_init (%p, %lx)\n", kernel_pg_dir, availmem);
#endif

	/* Fix the cache mode in the page descriptors for the 680[46]0.  */
	if (CPU_IS_040_OR_060) {
		int i;
#ifndef mm_cachebits
		mm_cachebits = _PAGE_CACHE040;
#endif
		for (i = 0; i < 16; i++)
			pgprot_val(protection_map[i]) |= _PAGE_CACHE040;
	}

	min_addr = m68k_memory[0].addr;
	max_addr = min_addr + m68k_memory[0].size;
	memblock_add_node(m68k_memory[0].addr, m68k_memory[0].size, 0,
			  MEMBLOCK_NONE);
	for (i = 1; i < m68k_num_memory;) {
		if (m68k_memory[i].addr < min_addr) {
			printk("Ignoring memory chunk at 0x%lx:0x%lx before the first chunk\n",
				m68k_memory[i].addr, m68k_memory[i].size);
			printk("Fix your bootloader or use a memfile to make use of this area!\n");
			m68k_num_memory--;
			memmove(m68k_memory + i, m68k_memory + i + 1,
				(m68k_num_memory - i) * sizeof(struct m68k_mem_info));
			continue;
		}
		memblock_add_node(m68k_memory[i].addr, m68k_memory[i].size, i,
				  MEMBLOCK_NONE);
		addr = m68k_memory[i].addr + m68k_memory[i].size;
		if (addr > max_addr)
			max_addr = addr;
		i++;
	}
	m68k_memoffset = min_addr - PAGE_OFFSET;
	m68k_virt_to_node_shift = fls(max_addr - min_addr - 1) - 6;

	module_fixup(NULL, __start_fixup, __stop_fixup);
	flush_icache();

	high_memory = phys_to_virt(max_addr);

	min_low_pfn = availmem >> PAGE_SHIFT;
	max_pfn = max_low_pfn = max_addr >> PAGE_SHIFT;

	/* Reserve kernel text/data/bss and the memory allocated in head.S */
	memblock_reserve(m68k_memory[0].addr, availmem - m68k_memory[0].addr);

	/*
	 * Map the physical memory available into the kernel virtual
	 * address space. Make sure memblock will not try to allocate
	 * pages beyond the memory we already mapped in head.S
	 */
	memblock_set_bottom_up(true);

	for (i = 0; i < m68k_num_memory; i++) {
		m68k_setup_node(i);
		map_node(i);
	}

	flush_tlb_all();

	early_memtest(min_addr, max_addr);

	/*
	 * initialize the bad page table and bad page to point
	 * to a couple of allocated pages
	 */
	empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
	if (!empty_zero_page)
		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
		      __func__, PAGE_SIZE, PAGE_SIZE);

	/*
	 * Set up SFC/DFC registers
	 */
	set_fc(USER_DATA);

#ifdef DEBUG
	printk ("before free_area_init\n");
#endif
	for (i = 0; i < m68k_num_memory; i++)
		if (node_present_pages(i))
			node_set_state(i, N_NORMAL_MEMORY);

	max_zone_pfn[ZONE_DMA] = memblock_end_of_DRAM();
	free_area_init(max_zone_pfn);
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4	2	/*
f30c2269	3	* linux/arch/m68k/mm/motorola.c
1da177e4 LT	4	*
	5	* Routines specific to the Motorola MMU, originally from:
	6	* linux/arch/m68k/init.c
	7	* which are Copyright (C) 1995 Hamish Macdonald
	8	*
	9	* Moved 8/20/1999 Sam Creasey
	10	*/
	11
1da177e4 LT	12	#include <linux/module.h>
	13	#include <linux/signal.h>
	14	#include <linux/sched.h>
	15	#include <linux/mm.h>
	16	#include <linux/swap.h>
	17	#include <linux/kernel.h>
	18	#include <linux/string.h>
	19	#include <linux/types.h>
	20	#include <linux/init.h>
1008a115	21	#include <linux/memblock.h>
5a0e3ad6	22	#include <linux/gfp.h>
1da177e4 LT	23
1da177e4 LT	24	#include <asm/setup.h>
7c0f6ba6	25	#include <linux/uaccess.h>
1da177e4 LT	26	#include <asm/page.h>
1da177e4 LT	27	#include <asm/pgalloc.h>
1da177e4 LT	28	#include <asm/machdep.h>
1da177e4 LT	29	#include <asm/io.h>
1da177e4 LT	30	#ifdef CONFIG_ATARI
	31	#include <asm/atari_stram.h>
	32	#endif
c85627fb	33	#include <asm/sections.h>
1da177e4 LT	34
	35	#undef DEBUG
	36
	37	#ifndef mm_cachebits
	38	/*
	39	* Bits to add to page descriptors for "normal" caching mode.
	40	* For 68020/030 this is 0.
	41	* For 68040, this is _PAGE_CACHE040 (cachable, copyback)
	42	*/
	43	unsigned long mm_cachebits;
	44	EXPORT_SYMBOL(mm_cachebits);
	45	#endif
	46
1bcdc68d MR	47	/* Prior to calling these routines, the page should have been flushed
	48	* from both the cache and ATC, or the CPU might not notice that the
	49	* cache setting for the page has been changed. -jskov
	50	*/
	51	static inline void nocache_page(void *vaddr)
	52	{
	53	unsigned long addr = (unsigned long)vaddr;
	54
	55	if (CPU_IS_040_OR_060) {
e05c7b1f	56	pte_t *ptep = virt_to_kpte(addr);
1bcdc68d	57
1bcdc68d MR	58	ptep = pte_mknocache(ptep);
	59	}
	60	}
	61
	62	static inline void cache_page(void *vaddr)
	63	{
	64	unsigned long addr = (unsigned long)vaddr;
	65
	66	if (CPU_IS_040_OR_060) {
e05c7b1f	67	pte_t *ptep = virt_to_kpte(addr);
1bcdc68d	68
1bcdc68d MR	69	ptep = pte_mkcache(ptep);
	70	}
	71	}
13076a29 PZ	72
	73	/*
	74	* Motorola 680x0 user's manual recommends using uncached memory for address
	75	* translation tables.
	76	*
	77	* Seeing how the MMU can be external on (some of) these chips, that seems like
	78	* a very important recommendation to follow. Provide some helpers to combat
	79	* 'variation' amongst the users of this.
	80	*/
	81
	82	void mmu_page_ctor(void *page)
	83	{
	84	__flush_page_to_ram(page);
	85	flush_tlb_kernel_page(page);
	86	nocache_page(page);
	87	}
	88
	89	void mmu_page_dtor(void *page)
	90	{
	91	cache_page(page);
	92	}
	93
5ad272ab PZ	94	/* ++andreas: {get,free}_pointer_table rewritten to use unused fields from
	95	struct page instead of separately kmalloced struct. Stolen from
	96	arch/sparc/mm/srmmu.c ... */
	97
	98	typedef struct list_head ptable_desc;
0e071ee6 PZ	99
	100	static struct list_head ptable_list[2] = {
	101	LIST_HEAD_INIT(ptable_list[0]),
	102	LIST_HEAD_INIT(ptable_list[1]),
	103	};
5ad272ab PZ	104
	105	#define PD_PTABLE(page) ((ptable_desc *)&(virt_to_page(page)->lru))
	106	#define PD_PAGE(ptable) (list_entry(ptable, struct page, lru))
0e071ee6 PZ	107	#define PD_MARKBITS(dp) ((unsigned int )&PD_PAGE(dp)->index)
	108
	109	static const int ptable_shift[2] = {
	110	7+2, /* PGD, PMD */
	111	6+2, /* PTE */
	112	};
5ad272ab	113
0e071ee6 PZ	114	#define ptable_size(type) (1U << ptable_shift[type])
0e071ee6 PZ	115	#define ptable_mask(type) ((1U << (PAGE_SIZE / ptable_size(type))) - 1)
5ad272ab	116
0e071ee6	117	void __init init_pointer_table(void *table, int type)
5ad272ab PZ	118	{
5ad272ab PZ	119	ptable_desc *dp;
0e071ee6	120	unsigned long ptable = (unsigned long)table;
5ad272ab	121	unsigned long page = ptable & PAGE_MASK;
0e071ee6	122	unsigned int mask = 1U << ((ptable - page)/ptable_size(type));
5ad272ab PZ	123
	124	dp = PD_PTABLE(page);
	125	if (!(PD_MARKBITS(dp) & mask)) {
0e071ee6 PZ	126	PD_MARKBITS(dp) = ptable_mask(type);
0e071ee6 PZ	127	list_add(dp, &ptable_list[type]);
5ad272ab PZ	128	}
	129
	130	PD_MARKBITS(dp) &= ~mask;
	131	pr_debug("init_pointer_table: %lx, %x\n", ptable, PD_MARKBITS(dp));
	132
	133	/* unreserve the page so it's possible to free that page */
	134	__ClearPageReserved(PD_PAGE(dp));
	135	init_page_count(PD_PAGE(dp));
	136
	137	return;
	138	}
	139
0e071ee6	140	void *get_pointer_table(int type)
5ad272ab	141	{
0e071ee6 PZ	142	ptable_desc *dp = ptable_list[type].next;
	143	unsigned int mask = list_empty(&ptable_list[type]) ? 0 : PD_MARKBITS(dp);
	144	unsigned int tmp, off;
5ad272ab PZ	145
	146	/*
	147	* For a pointer table for a user process address space, a
	148	* table is taken from a page allocated for the purpose. Each
	149	* page can hold 8 pointer tables. The page is remapped in
	150	* virtual address space to be noncacheable.
	151	*/
	152	if (mask == 0) {
	153	void *page;
	154	ptable_desc *new;
	155
	156	if (!(page = (void *)get_zeroed_page(GFP_KERNEL)))
	157	return NULL;
	158
0e071ee6 PZ	159	if (type == TABLE_PTE) {
	160	/*
	161	* m68k doesn't have SPLIT_PTE_PTLOCKS for not having
	162	* SMP.
	163	*/
	164	pgtable_pte_page_ctor(virt_to_page(page));
	165	}
	166
5ad272ab PZ	167	mmu_page_ctor(page);
	168
	169	new = PD_PTABLE(page);
0e071ee6	170	PD_MARKBITS(new) = ptable_mask(type) - 1;
5ad272ab PZ	171	list_add_tail(new, dp);
	172
	173	return (pmd_t *)page;
	174	}
	175
0e071ee6	176	for (tmp = 1, off = 0; (mask & tmp) == 0; tmp <<= 1, off += ptable_size(type))
5ad272ab PZ	177	;
	178	PD_MARKBITS(dp) = mask & ~tmp;
	179	if (!PD_MARKBITS(dp)) {
	180	/* move to end of list */
0e071ee6	181	list_move_tail(dp, &ptable_list[type]);
5ad272ab	182	}
0e071ee6	183	return page_address(PD_PAGE(dp)) + off;
5ad272ab PZ	184	}
5ad272ab PZ	185
0e071ee6	186	int free_pointer_table(void *table, int type)
5ad272ab PZ	187	{
5ad272ab PZ	188	ptable_desc *dp;
0e071ee6 PZ	189	unsigned long ptable = (unsigned long)table;
	190	unsigned long page = ptable & PAGE_MASK;
	191	unsigned int mask = 1U << ((ptable - page)/ptable_size(type));
5ad272ab PZ	192
	193	dp = PD_PTABLE(page);
	194	if (PD_MARKBITS (dp) & mask)
	195	panic ("table already free!");
	196
	197	PD_MARKBITS (dp) \|= mask;
	198
0e071ee6	199	if (PD_MARKBITS(dp) == ptable_mask(type)) {
5ad272ab PZ	200	/* all tables in page are free, free page */
	201	list_del(dp);
	202	mmu_page_dtor((void *)page);
0e071ee6 PZ	203	if (type == TABLE_PTE)
0e071ee6 PZ	204	pgtable_pte_page_dtor(virt_to_page(page));
5ad272ab PZ	205	free_page (page);
5ad272ab PZ	206	return 1;
0e071ee6	207	} else if (ptable_list[type].next != dp) {
5ad272ab PZ	208	/*
	209	* move this descriptor to the front of the list, since
	210	* it has one or more free tables.
	211	*/
0e071ee6	212	list_move(dp, &ptable_list[type]);
5ad272ab PZ	213	}
	214	return 0;
	215	}
	216
12d810c1	217	/* size of memory already mapped in head.S */
486df8bc	218	extern __initdata unsigned long m68k_init_mapped_size;
12d810c1 RZ	219
	220	extern unsigned long availmem;
	221
ef9285f6 PZ	222	static pte_t *last_pte_table __initdata = NULL;
ef9285f6 PZ	223
1da177e4 LT	224	static pte_t * __init kernel_page_table(void)
1da177e4 LT	225	{
ef9285f6	226	pte_t *pte_table = last_pte_table;
1da177e4	227
41f1bf37	228	if (PAGE_ALIGNED(last_pte_table)) {
7e158826	229	pte_table = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
ef9285f6 PZ	230	if (!pte_table) {
	231	panic("%s: Failed to allocate %lu bytes align=%lx\n",
	232	__func__, PAGE_SIZE, PAGE_SIZE);
	233	}
1da177e4	234
ef9285f6 PZ	235	clear_page(pte_table);
ef9285f6 PZ	236	mmu_page_ctor(pte_table);
1da177e4	237
ef9285f6 PZ	238	last_pte_table = pte_table;
	239	}
	240
	241	last_pte_table += PTRS_PER_PTE;
	242
	243	return pte_table;
1da177e4 LT	244	}
1da177e4 LT	245
ef9285f6	246	static pmd_t *last_pmd_table __initdata = NULL;
1da177e4 LT	247
	248	static pmd_t * __init kernel_ptr_table(void)
	249	{
ef9285f6	250	if (!last_pmd_table) {
1da177e4 LT	251	unsigned long pmd, last;
	252	int i;
	253
	254	/* Find the last ptr table that was used in head.S and
	255	* reuse the remaining space in that page for further
	256	* ptr tables.
	257	*/
	258	last = (unsigned long)kernel_pg_dir;
	259	for (i = 0; i < PTRS_PER_PGD; i++) {
60e50f34 MR	260	pud_t pud = (pud_t )(&kernel_pg_dir[i]);
	261
	262	if (!pud_present(*pud))
1da177e4	263	continue;
60e50f34	264	pmd = pgd_page_vaddr(kernel_pg_dir[i]);
1da177e4 LT	265	if (pmd > last)
	266	last = pmd;
	267	}
	268
ef9285f6	269	last_pmd_table = (pmd_t *)last;
1da177e4	270	#ifdef DEBUG
ef9285f6	271	printk("kernel_ptr_init: %p\n", last_pmd_table);
1da177e4 LT	272	#endif
	273	}
	274
ef9285f6	275	last_pmd_table += PTRS_PER_PMD;
41f1bf37	276	if (PAGE_ALIGNED(last_pmd_table)) {
7e158826	277	last_pmd_table = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
ef9285f6	278	if (!last_pmd_table)
8a7f97b9 MR	279	panic("%s: Failed to allocate %lu bytes align=%lx\n",
8a7f97b9 MR	280	__func__, PAGE_SIZE, PAGE_SIZE);
1da177e4	281
ef9285f6 PZ	282	clear_page(last_pmd_table);
ef9285f6 PZ	283	mmu_page_ctor(last_pmd_table);
1da177e4 LT	284	}
1da177e4 LT	285
ef9285f6	286	return last_pmd_table;
1da177e4 LT	287	}
1da177e4 LT	288
12d810c1	289	static void __init map_node(int node)
1da177e4	290	{
12d810c1	291	unsigned long physaddr, virtaddr, size;
1da177e4	292	pgd_t *pgd_dir;
60e50f34 MR	293	p4d_t *p4d_dir;
60e50f34 MR	294	pud_t *pud_dir;
1da177e4 LT	295	pmd_t *pmd_dir;
	296	pte_t *pte_dir;
	297
12d810c1 RZ	298	size = m68k_memory[node].size;
	299	physaddr = m68k_memory[node].addr;
	300	virtaddr = (unsigned long)phys_to_virt(physaddr);
	301	physaddr \|= m68k_supervisor_cachemode \|
	302	_PAGE_PRESENT \| _PAGE_ACCESSED \| _PAGE_DIRTY;
1da177e4 LT	303	if (CPU_IS_040_OR_060)
	304	physaddr \|= _PAGE_GLOBAL040;
	305
	306	while (size > 0) {
	307	#ifdef DEBUG
ef22d8ab	308	if (!(virtaddr & (PMD_SIZE-1)))
1da177e4 LT	309	printk ("\npa=%#lx va=%#lx ", physaddr & PAGE_MASK,
	310	virtaddr);
	311	#endif
	312	pgd_dir = pgd_offset_k(virtaddr);
	313	if (virtaddr && CPU_IS_020_OR_030) {
ef22d8ab PZ	314	if (!(virtaddr & (PGDIR_SIZE-1)) &&
ef22d8ab PZ	315	size >= PGDIR_SIZE) {
1da177e4 LT	316	#ifdef DEBUG
	317	printk ("[very early term]");
	318	#endif
	319	pgd_val(*pgd_dir) = physaddr;
ef22d8ab PZ	320	size -= PGDIR_SIZE;
	321	virtaddr += PGDIR_SIZE;
	322	physaddr += PGDIR_SIZE;
1da177e4 LT	323	continue;
	324	}
	325	}
60e50f34 MR	326	p4d_dir = p4d_offset(pgd_dir, virtaddr);
	327	pud_dir = pud_offset(p4d_dir, virtaddr);
	328	if (!pud_present(*pud_dir)) {
1da177e4 LT	329	pmd_dir = kernel_ptr_table();
	330	#ifdef DEBUG
	331	printk ("[new pointer %p]", pmd_dir);
	332	#endif
60e50f34	333	pud_set(pud_dir, pmd_dir);
1da177e4	334	} else
60e50f34	335	pmd_dir = pmd_offset(pud_dir, virtaddr);
1da177e4 LT	336
	337	if (CPU_IS_020_OR_030) {
	338	if (virtaddr) {
	339	#ifdef DEBUG
	340	printk ("[early term]");
	341	#endif
ef22d8ab PZ	342	pmd_val(*pmd_dir) = physaddr;
ef22d8ab PZ	343	physaddr += PMD_SIZE;
1da177e4 LT	344	} else {
	345	int i;
	346	#ifdef DEBUG
	347	printk ("[zero map]");
	348	#endif
ef9285f6	349	pte_dir = kernel_page_table();
ef22d8ab PZ	350	pmd_set(pmd_dir, pte_dir);
ef22d8ab PZ	351
1da177e4 LT	352	pte_val(*pte_dir++) = 0;
1da177e4 LT	353	physaddr += PAGE_SIZE;
ef22d8ab	354	for (i = 1; i < PTRS_PER_PTE; physaddr += PAGE_SIZE, i++)
1da177e4 LT	355	pte_val(*pte_dir++) = physaddr;
1da177e4 LT	356	}
ef22d8ab PZ	357	size -= PMD_SIZE;
ef22d8ab PZ	358	virtaddr += PMD_SIZE;
1da177e4 LT	359	} else {
	360	if (!pmd_present(*pmd_dir)) {
	361	#ifdef DEBUG
	362	printk ("[new table]");
	363	#endif
	364	pte_dir = kernel_page_table();
	365	pmd_set(pmd_dir, pte_dir);
	366	}
	367	pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
	368
	369	if (virtaddr) {
	370	if (!pte_present(*pte_dir))
	371	pte_val(*pte_dir) = physaddr;
	372	} else
	373	pte_val(*pte_dir) = 0;
	374	size -= PAGE_SIZE;
	375	virtaddr += PAGE_SIZE;
	376	physaddr += PAGE_SIZE;
	377	}
	378
	379	}
	380	#ifdef DEBUG
	381	printk("\n");
	382	#endif
1da177e4 LT	383	}
	384
	385	/*
	386	* paging_init() continues the virtual memory environment setup which
	387	* was begun by the code in arch/head.S.
	388	*/
	389	void __init paging_init(void)
	390	{
5d2ee1a1	391	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
12d810c1	392	unsigned long min_addr, max_addr;
1008a115	393	unsigned long addr;
12d810c1	394	int i;
1da177e4 LT	395
1da177e4 LT	396	#ifdef DEBUG
fb425d0b	397	printk ("start of paging_init (%p, %lx)\n", kernel_pg_dir, availmem);
1da177e4 LT	398	#endif
	399
	400	/* Fix the cache mode in the page descriptors for the 680[46]0. */
	401	if (CPU_IS_040_OR_060) {
	402	int i;
	403	#ifndef mm_cachebits
	404	mm_cachebits = _PAGE_CACHE040;
	405	#endif
	406	for (i = 0; i < 16; i++)
	407	pgprot_val(protection_map[i]) \|= _PAGE_CACHE040;
	408	}
	409
12d810c1 RZ	410	min_addr = m68k_memory[0].addr;
12d810c1 RZ	411	max_addr = min_addr + m68k_memory[0].size;
952eea9b DH	412	memblock_add_node(m68k_memory[0].addr, m68k_memory[0].size, 0,
952eea9b DH	413	MEMBLOCK_NONE);
12d810c1 RZ	414	for (i = 1; i < m68k_num_memory;) {
	415	if (m68k_memory[i].addr < min_addr) {
	416	printk("Ignoring memory chunk at 0x%lx:0x%lx before the first chunk\n",
	417	m68k_memory[i].addr, m68k_memory[i].size);
	418	printk("Fix your bootloader or use a memfile to make use of this area!\n");
	419	m68k_num_memory--;
	420	memmove(m68k_memory + i, m68k_memory + i + 1,
79930084	421	(m68k_num_memory - i) * sizeof(struct m68k_mem_info));
12d810c1 RZ	422	continue;
12d810c1 RZ	423	}
952eea9b DH	424	memblock_add_node(m68k_memory[i].addr, m68k_memory[i].size, i,
952eea9b DH	425	MEMBLOCK_NONE);
12d810c1 RZ	426	addr = m68k_memory[i].addr + m68k_memory[i].size;
	427	if (addr > max_addr)
	428	max_addr = addr;
	429	i++;
	430	}
	431	m68k_memoffset = min_addr - PAGE_OFFSET;
	432	m68k_virt_to_node_shift = fls(max_addr - min_addr - 1) - 6;
	433
fbe9c961 RZ	434	module_fixup(NULL, __start_fixup, __stop_fixup);
	435	flush_icache();
	436
12d810c1 RZ	437	high_memory = phys_to_virt(max_addr);
	438
	439	min_low_pfn = availmem >> PAGE_SHIFT;
79ae4fa5	440	max_pfn = max_low_pfn = max_addr >> PAGE_SHIFT;
12d810c1	441
1008a115 MR	442	/* Reserve kernel text/data/bss and the memory allocated in head.S */
1008a115 MR	443	memblock_reserve(m68k_memory[0].addr, availmem - m68k_memory[0].addr);
12d810c1	444
1da177e4 LT	445	/*
1da177e4 LT	446	* Map the physical memory available into the kernel virtual
1008a115 MR	447	* address space. Make sure memblock will not try to allocate
1008a115 MR	448	* pages beyond the memory we already mapped in head.S
1da177e4	449	*/
1008a115 MR	450	memblock_set_bottom_up(true);
	451
	452	for (i = 0; i < m68k_num_memory; i++) {
	453	m68k_setup_node(i);
12d810c1	454	map_node(i);
1008a115	455	}
1da177e4 LT	456
1da177e4 LT	457	flush_tlb_all();
1da177e4	458
376e3fde FT	459	early_memtest(min_addr, max_addr);
376e3fde FT	460
1da177e4 LT	461	/*
	462	* initialize the bad page table and bad page to point
	463	* to a couple of allocated pages
	464	*/
15c3c114	465	empty_zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
8a7f97b9 MR	466	if (!empty_zero_page)
	467	panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
	468	__func__, PAGE_SIZE, PAGE_SIZE);
1da177e4 LT	469
	470	/*
	471	* Set up SFC/DFC registers
	472	*/
9fde0348	473	set_fc(USER_DATA);
1da177e4 LT	474
	475	#ifdef DEBUG
	476	printk ("before free_area_init\n");
	477	#endif
5d2ee1a1	478	for (i = 0; i < m68k_num_memory; i++)
4aac0b48 MS	479	if (node_present_pages(i))
4aac0b48 MS	480	node_set_state(i, N_NORMAL_MEMORY);
5d2ee1a1 MR	481
	482	max_zone_pfn[ZONE_DMA] = memblock_end_of_DRAM();
	483	free_area_init(max_zone_pfn);
1da177e4	484	}