[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / xtensa / mm / init.c

/*
 * arch/xtensa/mm/init.c
 *
 * Derived from MIPS, PPC.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2001 - 2005 Tensilica Inc.
 *
 * Chris Zankel	<chris@zankel.net>
 * Joe Taylor	<joe@tensilica.com, joetylr@yahoo.com>
 * Marc Gauthier
 * Kevin Chea
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/bootmem.h>
#include <linux/swap.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/mm.h>
#include <linux/slab.h>

#include <asm/pgtable.h>
#include <asm/bootparam.h>
#include <asm/mmu_context.h>
#include <asm/tlb.h>
#include <asm/page.h>
#include <asm/pgalloc.h>


DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

/* References to section boundaries */

extern char _ftext, _etext, _fdata, _edata, _rodata_end;
extern char __init_begin, __init_end;

/*
 * mem_reserve(start, end, must_exist)
 *
 * Reserve some memory from the memory pool.
 *
 * Parameters:
 *  start	Start of region,
 *  end		End of region,
 *  must_exist	Must exist in memory pool.
 *
 * Returns:
 *  0 (memory area couldn't be mapped)
 * -1 (success)
 */

int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
{
	int i;

	if (start == end)
		return 0;

	start = start & PAGE_MASK;
	end = PAGE_ALIGN(end);

	for (i = 0; i < sysmem.nr_banks; i++)
		if (start < sysmem.bank[i].end
		    && end >= sysmem.bank[i].start)
			break;

	if (i == sysmem.nr_banks) {
		if (must_exist)
			printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) "
				"not in any region!\n", start, end);
		return 0;
	}

	if (start > sysmem.bank[i].start) {
		if (end < sysmem.bank[i].end) {
			/* split entry */
			if (sysmem.nr_banks >= SYSMEM_BANKS_MAX)
				panic("meminfo overflow\n");
			sysmem.bank[sysmem.nr_banks].start = end;
			sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end;
			sysmem.nr_banks++;
		}
		sysmem.bank[i].end = start;
	} else {
		if (end < sysmem.bank[i].end)
			sysmem.bank[i].start = end;
		else {
			/* remove entry */
			sysmem.nr_banks--;
			sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start;
			sysmem.bank[i].end   = sysmem.bank[sysmem.nr_banks].end;
		}
	}
	return -1;
}


/*
 * Initialize the bootmem system and give it all the memory we have available.
 */

void __init bootmem_init(void)
{
	unsigned long pfn;
	unsigned long bootmap_start, bootmap_size;
	int i;

	max_low_pfn = max_pfn = 0;
	min_low_pfn = ~0;

	for (i=0; i < sysmem.nr_banks; i++) {
		pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT;
		if (pfn < min_low_pfn)
			min_low_pfn = pfn;
		pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT;
		if (pfn > max_pfn)
			max_pfn = pfn;
	}

	if (min_low_pfn > max_pfn)
		panic("No memory found!\n");

	max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ?
		max_pfn : MAX_MEM_PFN >> PAGE_SHIFT;

	/* Find an area to use for the bootmem bitmap. */

	bootmap_size = bootmem_bootmap_pages(max_low_pfn) << PAGE_SHIFT;
	bootmap_start = ~0;

	for (i=0; i<sysmem.nr_banks; i++)
		if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) {
			bootmap_start = sysmem.bank[i].start;
			break;
		}

	if (bootmap_start == ~0UL)
		panic("Cannot find %ld bytes for bootmap\n", bootmap_size);

	/* Reserve the bootmem bitmap area */

	mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1);
	bootmap_size = init_bootmem_node(NODE_DATA(0),
					 bootmap_start >> PAGE_SHIFT,
					 min_low_pfn,
					 max_low_pfn);

	/* Add all remaining memory pieces into the bootmem map */

	for (i=0; i<sysmem.nr_banks; i++)
		free_bootmem(sysmem.bank[i].start,
			     sysmem.bank[i].end - sysmem.bank[i].start);

}


void __init paging_init(void)
{
	unsigned long zones_size[MAX_NR_ZONES];
	int i;

	/* All pages are DMA-able, so we put them all in the DMA zone. */

	zones_size[ZONE_DMA] = max_low_pfn;
	for (i = 1; i < MAX_NR_ZONES; i++)
		zones_size[i] = 0;

#ifdef CONFIG_HIGHMEM
	zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
#endif

	/* Initialize the kernel's page tables. */

	memset(swapper_pg_dir, 0, PAGE_SIZE);

	free_area_init(zones_size);
}

/*
 * Flush the mmu and reset associated register to default values.
 */

void __init init_mmu (void)
{
	/* Writing zeros to the <t>TLBCFG special registers ensure
	 * that valid values exist in the register.  For existing
	 * PGSZID<w> fields, zero selects the first element of the
	 * page-size array.  For nonexistent PGSZID<w> fields, zero is
	 * the best value to write.  Also, when changing PGSZID<w>
	 * fields, the corresponding TLB must be flushed.
	 */
	set_itlbcfg_register (0);
	set_dtlbcfg_register (0);
	flush_tlb_all ();

	/* Set rasid register to a known value. */

	set_rasid_register (ASID_USER_FIRST);

	/* Set PTEVADDR special register to the start of the page
	 * table, which is in kernel mappable space (ie. not
	 * statically mapped).  This register's value is undefined on
	 * reset.
	 */
	set_ptevaddr_register (PGTABLE_START);
}

/*
 * Initialize memory pages.
 */

void __init mem_init(void)
{
	unsigned long codesize, reservedpages, datasize, initsize;
	unsigned long highmemsize, tmp, ram;

	max_mapnr = num_physpages = max_low_pfn;
	high_memory = (void *) __va(max_mapnr << PAGE_SHIFT);
	highmemsize = 0;

#ifdef CONFIG_HIGHMEM
#error HIGHGMEM not implemented in init.c
#endif

	totalram_pages += free_all_bootmem();

	reservedpages = ram = 0;
	for (tmp = 0; tmp < max_low_pfn; tmp++) {
		ram++;
		if (PageReserved(mem_map+tmp))
			reservedpages++;
	}

	codesize =  (unsigned long) &_etext - (unsigned long) &_ftext;
	datasize =  (unsigned long) &_edata - (unsigned long) &_fdata;
	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;

	printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, "
	       "%ldk data, %ldk init %ldk highmem)\n",
	       (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
	       ram << (PAGE_SHIFT-10),
	       codesize >> 10,
	       reservedpages << (PAGE_SHIFT-10),
	       datasize >> 10,
	       initsize >> 10,
	       highmemsize >> 10);
}

void
free_reserved_mem(void *start, void *end)
{
	for (; start < end; start += PAGE_SIZE) {
		ClearPageReserved(virt_to_page(start));
		init_page_count(virt_to_page(start));
		free_page((unsigned long)start);
		totalram_pages++;
	}
}

#ifdef CONFIG_BLK_DEV_INITRD
extern int initrd_is_mapped;

void free_initrd_mem(unsigned long start, unsigned long end)
{
	if (initrd_is_mapped) {
		free_reserved_mem((void*)start, (void*)end);
		printk ("Freeing initrd memory: %ldk freed\n",(end-start)>>10);
	}
}
#endif

void free_initmem(void)
{
	free_reserved_mem(&__init_begin, &__init_end);
	printk("Freeing unused kernel memory: %dk freed\n",
	       (&__init_end - &__init_begin) >> 10);
}

struct kmem_cache *pgtable_cache __read_mostly;

static void pgd_ctor(void* addr)
{
	pte_t* ptep = (pte_t*)addr;
	int i;

	for (i = 0; i < 1024; i++, ptep++)
		pte_clear(NULL, 0, ptep);

}

void __init pgtable_cache_init(void)
{
	pgtable_cache = kmem_cache_create("pgd",
			PAGE_SIZE, PAGE_SIZE,
			SLAB_HWCACHE_ALIGN,
			pgd_ctor);
}
Commit	Line	Data
3f65ce4d CZ	1	/*
	2	* arch/xtensa/mm/init.c
	3	*
	4	* Derived from MIPS, PPC.
	5	*
	6	* This file is subject to the terms and conditions of the GNU General Public
	7	* License. See the file "COPYING" in the main directory of this archive
	8	* for more details.
	9	*
	10	* Copyright (C) 2001 - 2005 Tensilica Inc.
	11	*
	12	* Chris Zankel <chris@zankel.net>
	13	* Joe Taylor <joe@tensilica.com, joetylr@yahoo.com>
	14	* Marc Gauthier
	15	* Kevin Chea
	16	*/
	17
3f65ce4d CZ	18	#include <linux/kernel.h>
3f65ce4d CZ	19	#include <linux/errno.h>
3f65ce4d CZ	20	#include <linux/bootmem.h>
3f65ce4d CZ	21	#include <linux/swap.h>
6656920b CZ	22	#include <linux/mman.h>
	23	#include <linux/nodemask.h>
	24	#include <linux/mm.h>
	25	#include <linux/slab.h>
3f65ce4d CZ	26
	27	#include <asm/pgtable.h>
	28	#include <asm/bootparam.h>
	29	#include <asm/mmu_context.h>
	30	#include <asm/tlb.h>
3f65ce4d CZ	31	#include <asm/page.h>
3f65ce4d CZ	32	#include <asm/pgalloc.h>
3f65ce4d	33
3f65ce4d CZ	34
3f65ce4d CZ	35	DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
3f65ce4d CZ	36
	37	/* References to section boundaries */
	38
	39	extern char _ftext, _etext, _fdata, _edata, _rodata_end;
	40	extern char __init_begin, __init_end;
	41
	42	/*
	43	* mem_reserve(start, end, must_exist)
	44	*
	45	* Reserve some memory from the memory pool.
	46	*
	47	* Parameters:
	48	* start Start of region,
	49	* end End of region,
	50	* must_exist Must exist in memory pool.
	51	*
	52	* Returns:
	53	* 0 (memory area couldn't be mapped)
	54	* -1 (success)
	55	*/
	56
	57	int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
	58	{
	59	int i;
	60
	61	if (start == end)
	62	return 0;
	63
	64	start = start & PAGE_MASK;
	65	end = PAGE_ALIGN(end);
	66
	67	for (i = 0; i < sysmem.nr_banks; i++)
	68	if (start < sysmem.bank[i].end
	69	&& end >= sysmem.bank[i].start)
	70	break;
	71
	72	if (i == sysmem.nr_banks) {
	73	if (must_exist)
	74	printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) "
	75	"not in any region!\n", start, end);
	76	return 0;
	77	}
	78
	79	if (start > sysmem.bank[i].start) {
	80	if (end < sysmem.bank[i].end) {
	81	/* split entry */
	82	if (sysmem.nr_banks >= SYSMEM_BANKS_MAX)
	83	panic("meminfo overflow\n");
	84	sysmem.bank[sysmem.nr_banks].start = end;
	85	sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end;
	86	sysmem.nr_banks++;
	87	}
	88	sysmem.bank[i].end = start;
	89	} else {
	90	if (end < sysmem.bank[i].end)
	91	sysmem.bank[i].start = end;
	92	else {
	93	/* remove entry */
	94	sysmem.nr_banks--;
	95	sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start;
	96	sysmem.bank[i].end = sysmem.bank[sysmem.nr_banks].end;
	97	}
	98	}
	99	return -1;
100	}
101
102
103	/*
104	* Initialize the bootmem system and give it all the memory we have available.
105	*/
106
107	void __init bootmem_init(void)
108	{
109	unsigned long pfn;
110	unsigned long bootmap_start, bootmap_size;
111	int i;
112
113	max_low_pfn = max_pfn = 0;
114	min_low_pfn = ~0;
115
116	for (i=0; i < sysmem.nr_banks; i++) {
117	pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT;
118	if (pfn < min_low_pfn)
119	min_low_pfn = pfn;
120	pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT;
121	if (pfn > max_pfn)
122	max_pfn = pfn;
123	}
124
125	if (min_low_pfn > max_pfn)
126	panic("No memory found!\n");
127
173d6681 CZ	128	max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ?
173d6681 CZ	129	max_pfn : MAX_MEM_PFN >> PAGE_SHIFT;
3f65ce4d CZ	130
	131	/* Find an area to use for the bootmem bitmap. */
	132
	133	bootmap_size = bootmem_bootmap_pages(max_low_pfn) << PAGE_SHIFT;
	134	bootmap_start = ~0;
	135
	136	for (i=0; i<sysmem.nr_banks; i++)
	137	if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) {
	138	bootmap_start = sysmem.bank[i].start;
	139	break;
	140	}
	141
	142	if (bootmap_start == ~0UL)
	143	panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
	144
	145	/* Reserve the bootmem bitmap area */
	146
	147	mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1);
0bef42e5	148	bootmap_size = init_bootmem_node(NODE_DATA(0),
3f65ce4d	149	bootmap_start >> PAGE_SHIFT,
0bef42e5	150	min_low_pfn,
3f65ce4d CZ	151	max_low_pfn);
	152
	153	/* Add all remaining memory pieces into the bootmem map */
	154
	155	for (i=0; i<sysmem.nr_banks; i++)
	156	free_bootmem(sysmem.bank[i].start,
	157	sysmem.bank[i].end - sysmem.bank[i].start);
	158
	159	}
	160
	161
	162	void __init paging_init(void)
	163	{
	164	unsigned long zones_size[MAX_NR_ZONES];
	165	int i;
	166
	167	/* All pages are DMA-able, so we put them all in the DMA zone. */
	168
	169	zones_size[ZONE_DMA] = max_low_pfn;
	170	for (i = 1; i < MAX_NR_ZONES; i++)
	171	zones_size[i] = 0;
	172
	173	#ifdef CONFIG_HIGHMEM
	174	zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
	175	#endif
	176
	177	/* Initialize the kernel's page tables. */
	178
	179	memset(swapper_pg_dir, 0, PAGE_SIZE);
	180
	181	free_area_init(zones_size);
	182	}
	183
	184	/*
	185	* Flush the mmu and reset associated register to default values.
	186	*/
	187
	188	void __init init_mmu (void)
	189	{
	190	/* Writing zeros to the <t>TLBCFG special registers ensure
	191	* that valid values exist in the register. For existing
	192	* PGSZID<w> fields, zero selects the first element of the
4af410a8	193	* page-size array. For nonexistent PGSZID<w> fields, zero is
3f65ce4d CZ	194	* the best value to write. Also, when changing PGSZID<w>
	195	* fields, the corresponding TLB must be flushed.
	196	*/
	197	set_itlbcfg_register (0);
	198	set_dtlbcfg_register (0);
	199	flush_tlb_all ();
	200
	201	/* Set rasid register to a known value. */
	202
173d6681	203	set_rasid_register (ASID_USER_FIRST);
3f65ce4d CZ	204
	205	/* Set PTEVADDR special register to the start of the page
	206	* table, which is in kernel mappable space (ie. not
	207	* statically mapped). This register's value is undefined on
	208	* reset.
	209	*/
	210	set_ptevaddr_register (PGTABLE_START);
	211	}
	212
	213	/*
	214	* Initialize memory pages.
	215	*/
	216
	217	void __init mem_init(void)
	218	{
	219	unsigned long codesize, reservedpages, datasize, initsize;
	220	unsigned long highmemsize, tmp, ram;
	221
	222	max_mapnr = num_physpages = max_low_pfn;
	223	high_memory = (void *) __va(max_mapnr << PAGE_SHIFT);
	224	highmemsize = 0;
	225
288a60cf	226	#ifdef CONFIG_HIGHMEM
3f65ce4d CZ	227	#error HIGHGMEM not implemented in init.c
	228	#endif
	229
	230	totalram_pages += free_all_bootmem();
	231
	232	reservedpages = ram = 0;
	233	for (tmp = 0; tmp < max_low_pfn; tmp++) {
	234	ram++;
	235	if (PageReserved(mem_map+tmp))
	236	reservedpages++;
	237	}
	238
	239	codesize = (unsigned long) &_etext - (unsigned long) &_ftext;
	240	datasize = (unsigned long) &_edata - (unsigned long) &_fdata;
	241	initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
	242
	243	printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, "
	244	"%ldk data, %ldk init %ldk highmem)\n",
	245	(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
	246	ram << (PAGE_SHIFT-10),
	247	codesize >> 10,
	248	reservedpages << (PAGE_SHIFT-10),
	249	datasize >> 10,
	250	initsize >> 10,
	251	highmemsize >> 10);
	252	}
	253
	254	void
	255	free_reserved_mem(void start, void end)
	256	{
	257	for (; start < end; start += PAGE_SIZE) {
	258	ClearPageReserved(virt_to_page(start));
7835e98b	259	init_page_count(virt_to_page(start));
3f65ce4d CZ	260	free_page((unsigned long)start);
	261	totalram_pages++;
	262	}
	263	}
	264
	265	#ifdef CONFIG_BLK_DEV_INITRD
	266	extern int initrd_is_mapped;
	267
	268	void free_initrd_mem(unsigned long start, unsigned long end)
	269	{
	270	if (initrd_is_mapped) {
	271	free_reserved_mem((void)start, (void)end);
	272	printk ("Freeing initrd memory: %ldk freed\n",(end-start)>>10);
	273	}
	274	}
	275	#endif
	276
	277	void free_initmem(void)
	278	{
	279	free_reserved_mem(&__init_begin, &__init_end);
	280	printk("Freeing unused kernel memory: %dk freed\n",
	281	(&__init_end - &__init_begin) >> 10);
	282	}
	283
6656920b	284	struct kmem_cache *pgtable_cache __read_mostly;
3f65ce4d	285
51cc5068	286	static void pgd_ctor(void* addr)
3f65ce4d	287	{
6656920b CZ	288	pte_t* ptep = (pte_t*)addr;
6656920b CZ	289	int i;
3f65ce4d	290
6656920b CZ	291	for (i = 0; i < 1024; i++, ptep++)
6656920b CZ	292	pte_clear(NULL, 0, ptep);
3f65ce4d	293
3f65ce4d CZ	294	}
3f65ce4d CZ	295
6656920b	296	void __init pgtable_cache_init(void)
3f65ce4d	297	{
6656920b CZ	298	pgtable_cache = kmem_cache_create("pgd",
	299	PAGE_SIZE, PAGE_SIZE,
	300	SLAB_HWCACHE_ALIGN,
	301	pgd_ctor);
3f65ce4d	302	}