1/* MN10300 Memory management initialisation
2 *
3 * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
4 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5 * Modified by David Howells (dhowells@redhat.com)
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public Licence
9 * as published by the Free Software Foundation; either version
10 * 2 of the Licence, or (at your option) any later version.
11 */
12#include <linux/signal.h>
13#include <linux/sched.h>
14#include <linux/kernel.h>
15#include <linux/errno.h>
16#include <linux/string.h>
17#include <linux/types.h>
18#include <linux/ptrace.h>
19#include <linux/mman.h>
20#include <linux/fs.h>
21#include <linux/mm.h>
22#include <linux/swap.h>
23#include <linux/smp.h>
24#include <linux/init.h>
25#include <linux/initrd.h>
26#include <linux/highmem.h>
27#include <linux/pagemap.h>
28#include <linux/bootmem.h>
29#include <linux/gfp.h>
30
31#include <asm/processor.h>
32#include <asm/uaccess.h>
33#include <asm/pgtable.h>
34#include <asm/pgalloc.h>
35#include <asm/dma.h>
36#include <asm/tlb.h>
37#include <asm/sections.h>
38
39unsigned long highstart_pfn, highend_pfn;
40
41#ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT
42static struct vm_struct user_iomap_vm;
43#endif
44
45/*
46 * set up paging
47 */
48void __init paging_init(void)
49{
50	unsigned long zones_size[MAX_NR_ZONES] = {0,};
51	pte_t *ppte;
52	int loop;
53
54	/* main kernel space -> RAM mapping is handled as 1:1 transparent by
55	 * the MMU */
56	memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
57	memset(kernel_vmalloc_ptes, 0, sizeof(kernel_vmalloc_ptes));
58
59	/* load the VMALLOC area PTE table addresses into the kernel PGD */
60	ppte = kernel_vmalloc_ptes;
61	for (loop = VMALLOC_START / (PAGE_SIZE * PTRS_PER_PTE);
62	     loop < VMALLOC_END / (PAGE_SIZE * PTRS_PER_PTE);
63	     loop++
64	     ) {
65		set_pgd(swapper_pg_dir + loop, __pgd(__pa(ppte) | _PAGE_TABLE));
66		ppte += PAGE_SIZE / sizeof(pte_t);
67	}
68
69	/* declare the sizes of the RAM zones (only use the normal zone) */
70	zones_size[ZONE_NORMAL] =
71		contig_page_data.bdata->node_low_pfn -
72		contig_page_data.bdata->node_min_pfn;
73
74	/* pass the memory from the bootmem allocator to the main allocator */
75	free_area_init(zones_size);
76
77#ifdef CONFIG_MN10300_HAS_ATOMIC_OPS_UNIT
78	/* The Atomic Operation Unit registers need to be mapped to userspace
79	 * for all processes.  The following uses vm_area_register_early() to
80	 * reserve the first page of the vmalloc area and sets the pte for that
81	 * page.
82	 *
83	 * glibc hardcodes this virtual mapping, so we're pretty much stuck with
84	 * it from now on.
85	 */
86	user_iomap_vm.flags = VM_USERMAP;
87	user_iomap_vm.size = 1 << PAGE_SHIFT;
88	vm_area_register_early(&user_iomap_vm, PAGE_SIZE);
89	ppte = kernel_vmalloc_ptes;
90	set_pte(ppte, pfn_pte(USER_ATOMIC_OPS_PAGE_ADDR >> PAGE_SHIFT,
91			      PAGE_USERIO));
92#endif
93
94	local_flush_tlb_all();
95}
96
97/*
98 * transfer all the memory from the bootmem allocator to the runtime allocator
99 */
100void __init mem_init(void)
101{
102	BUG_ON(!mem_map);
103
104#define START_PFN	(contig_page_data.bdata->node_min_pfn)
105#define MAX_LOW_PFN	(contig_page_data.bdata->node_low_pfn)
106
107	max_mapnr = MAX_LOW_PFN - START_PFN;
108	high_memory = (void *) __va(MAX_LOW_PFN * PAGE_SIZE);
109
110	/* clear the zero-page */
111	memset(empty_zero_page, 0, PAGE_SIZE);
112
113	/* this will put all low memory onto the freelists */
114	free_all_bootmem();
115
116	mem_init_print_info(NULL);
117}
118
119/*
120 * recycle memory containing stuff only required for initialisation
121 */
122void free_initmem(void)
123{
124	free_initmem_default(POISON_FREE_INITMEM);
125}
126
127/*
128 * dispose of the memory on which the initial ramdisk resided
129 */
130#ifdef CONFIG_BLK_DEV_INITRD
131void free_initrd_mem(unsigned long start, unsigned long end)
132{
133	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
134			   "initrd");
135}
136#endif
137