2 * File: arch/blackfin/mm/init.c
10 * Copyright 2004-2007 Analog Devices Inc.
12 * Bugs: Enter bugs at http://blackfin.uclinux.org/
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, see the file COPYING, or write
26 * to the Free Software Foundation, Inc.,
27 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
30 #include <linux/swap.h>
31 #include <linux/bootmem.h>
32 #include <linux/uaccess.h>
33 #include <asm/bfin-global.h>
35 #include <asm/cplbinit.h>
36 #include <asm/early_printk.h>
37 #include "blackfin_sram.h"
40 * BAD_PAGE is the page that is used for page faults when linux
41 * is out-of-memory. Older versions of linux just did a
42 * do_exit(), but using this instead means there is less risk
43 * for a process dying in kernel mode, possibly leaving a inode
46 * BAD_PAGETABLE is the accompanying page-table: it is initialized
47 * to point to BAD_PAGE entries.
49 * ZERO_PAGE is a special page that is used for zero-initialized
52 static unsigned long empty_bad_page_table;
54 static unsigned long empty_bad_page;
56 static unsigned long empty_zero_page;
58 #ifndef CONFIG_EXCEPTION_L1_SCRATCH
59 #if defined CONFIG_SYSCALL_TAB_L1
60 __attribute__((l1_data))
62 static unsigned long exception_stack[NR_CPUS][1024];
65 struct blackfin_pda cpu_pda[NR_CPUS];
66 EXPORT_SYMBOL(cpu_pda);
69 * paging_init() continues the virtual memory environment setup which
70 * was begun by the code in arch/head.S.
71 * The parameters are pointers to where to stick the starting and ending
72 * addresses of available kernel virtual memory.
74 void __init paging_init(void)
77 * make sure start_mem is page aligned, otherwise bootmem and
78 * page_alloc get different views og the world
80 unsigned long end_mem = memory_end & PAGE_MASK;
82 pr_debug("start_mem is %#lx virtual_end is %#lx\n", PAGE_ALIGN(memory_start), end_mem);
85 * initialize the bad page table and bad page to point
86 * to a couple of allocated pages
88 empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
89 empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
90 empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
91 memset((void *)empty_zero_page, 0, PAGE_SIZE);
94 * Set up SFC/DFC registers (user data space)
98 pr_debug("free_area_init -> start_mem is %#lx virtual_end is %#lx\n",
99 PAGE_ALIGN(memory_start), end_mem);
102 unsigned long zones_size[MAX_NR_ZONES] = { 0, };
104 zones_size[ZONE_DMA] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
105 zones_size[ZONE_NORMAL] = 0;
106 #ifdef CONFIG_HIGHMEM
107 zones_size[ZONE_HIGHMEM] = 0;
109 free_area_init(zones_size);
113 asmlinkage void __init init_pda(void)
115 unsigned int cpu = raw_smp_processor_id();
117 early_shadow_stamp();
119 /* Initialize the PDA fields holding references to other parts
120 of the memory. The content of such memory is still
121 undefined at the time of the call, we are only setting up
122 valid pointers to it. */
123 memset(&cpu_pda[cpu], 0, sizeof(cpu_pda[cpu]));
125 cpu_pda[0].next = &cpu_pda[1];
126 cpu_pda[1].next = &cpu_pda[0];
128 #ifdef CONFIG_EXCEPTION_L1_SCRATCH
129 cpu_pda[cpu].ex_stack = (unsigned long *)(L1_SCRATCH_START + \
132 cpu_pda[cpu].ex_stack = exception_stack[cpu + 1];
136 cpu_pda[cpu].imask = 0x1f;
140 void __init mem_init(void)
142 unsigned int codek = 0, datak = 0, initk = 0;
143 unsigned int reservedpages = 0, freepages = 0;
145 unsigned long start_mem = memory_start;
146 unsigned long end_mem = memory_end;
148 end_mem &= PAGE_MASK;
149 high_memory = (void *)end_mem;
151 start_mem = PAGE_ALIGN(start_mem);
152 max_mapnr = num_physpages = MAP_NR(high_memory);
153 printk(KERN_DEBUG "Kernel managed physical pages: %lu\n", num_physpages);
155 /* This will put all memory onto the freelists. */
156 totalram_pages = free_all_bootmem();
159 for (tmp = 0; tmp < max_mapnr; tmp++)
160 if (PageReserved(pfn_to_page(tmp)))
162 freepages = max_mapnr - reservedpages;
164 /* do not count in kernel image between _rambase and _ramstart */
165 reservedpages -= (_ramstart - _rambase) >> PAGE_SHIFT;
166 #if (defined(CONFIG_BFIN_EXTMEM_ICACHEABLE) && ANOMALY_05000263)
167 reservedpages += (_ramend - memory_end - DMA_UNCACHED_REGION) >> PAGE_SHIFT;
170 codek = (_etext - _stext) >> 10;
171 initk = (__init_end - __init_begin) >> 10;
172 datak = ((_ramstart - _rambase) >> 10) - codek - initk;
175 "Memory available: %luk/%luk RAM, "
176 "(%uk init code, %uk kernel code, %uk data, %uk dma, %uk reserved)\n",
177 (unsigned long) freepages << (PAGE_SHIFT-10), _ramend >> 10,
178 initk, codek, datak, DMA_UNCACHED_REGION >> 10, (reservedpages << (PAGE_SHIFT-10)));
181 static void __init free_init_pages(const char *what, unsigned long begin, unsigned long end)
184 /* next to check that the page we free is not a partial page */
185 for (addr = begin; addr + PAGE_SIZE <= end; addr += PAGE_SIZE) {
186 ClearPageReserved(virt_to_page(addr));
187 init_page_count(virt_to_page(addr));
191 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
194 #ifdef CONFIG_BLK_DEV_INITRD
195 void __init free_initrd_mem(unsigned long start, unsigned long end)
198 free_init_pages("initrd memory", start, end);
203 void __init_refok free_initmem(void)
205 #if defined CONFIG_RAMKERNEL && !defined CONFIG_MPU
206 free_init_pages("unused kernel memory",
207 (unsigned long)(&__init_begin),
208 (unsigned long)(&__init_end));