1 /*
2 * Copyright 2004-2009 Analog Devices Inc.
3 *
4 * Licensed under the GPL-2 or later.
5 */
6
7 #include <linux/gfp.h>
8 #include <linux/swap.h>
9 #include <linux/bootmem.h>
10 #include <linux/uaccess.h>
11 #include <linux/export.h>
12 #include <asm/bfin-global.h>
13 #include <asm/pda.h>
14 #include <asm/cplbinit.h>
15 #include <asm/early_printk.h>
16 #include "blackfin_sram.h"
17
18 /*
19 * ZERO_PAGE is a special page that is used for zero-initialized data and COW.
20 * Let the bss do its zero-init magic so we don't have to do it ourselves.
21 */
22 char empty_zero_page[PAGE_SIZE] __attribute__((aligned(PAGE_SIZE)));
23 EXPORT_SYMBOL(empty_zero_page);
24
25 #ifndef CONFIG_EXCEPTION_L1_SCRATCH
26 #if defined CONFIG_SYSCALL_TAB_L1
27 __attribute__((l1_data))
28 #endif
29 static unsigned long exception_stack[NR_CPUS][1024];
30 #endif
31
32 struct blackfin_pda cpu_pda[NR_CPUS];
33 EXPORT_SYMBOL(cpu_pda);
34
35 /*
36 * paging_init() continues the virtual memory environment setup which
37 * was begun by the code in arch/head.S.
38 * The parameters are pointers to where to stick the starting and ending
39 * addresses of available kernel virtual memory.
40 */
paging_init(void)41 void __init paging_init(void)
42 {
43 /*
44 * make sure start_mem is page aligned, otherwise bootmem and
45 * page_alloc get different views of the world
46 */
47 unsigned long end_mem = memory_end & PAGE_MASK;
48
49 unsigned long zones_size[MAX_NR_ZONES] = {
50 [0] = 0,
51 [ZONE_DMA] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT,
52 [ZONE_NORMAL] = 0,
53 #ifdef CONFIG_HIGHMEM
54 [ZONE_HIGHMEM] = 0,
55 #endif
56 };
57
58 /* Set up SFC/DFC registers (user data space) */
59 set_fs(KERNEL_DS);
60
61 pr_debug("free_area_init -> start_mem is %#lx virtual_end is %#lx\n",
62 PAGE_ALIGN(memory_start), end_mem);
63 free_area_init(zones_size);
64 }
65
init_pda(void)66 asmlinkage void __init init_pda(void)
67 {
68 unsigned int cpu = raw_smp_processor_id();
69
70 early_shadow_stamp();
71
72 /* Initialize the PDA fields holding references to other parts
73 of the memory. The content of such memory is still
74 undefined at the time of the call, we are only setting up
75 valid pointers to it. */
76 memset(&cpu_pda[cpu], 0, sizeof(cpu_pda[cpu]));
77
78 cpu_pda[0].next = &cpu_pda[1];
79 cpu_pda[1].next = &cpu_pda[0];
80
81 #ifdef CONFIG_EXCEPTION_L1_SCRATCH
82 cpu_pda[cpu].ex_stack = (unsigned long *)(L1_SCRATCH_START + \
83 L1_SCRATCH_LENGTH);
84 #else
85 cpu_pda[cpu].ex_stack = exception_stack[cpu + 1];
86 #endif
87
88 #ifdef CONFIG_SMP
89 cpu_pda[cpu].imask = 0x1f;
90 #endif
91 }
92
mem_init(void)93 void __init mem_init(void)
94 {
95 unsigned int codek = 0, datak = 0, initk = 0;
96 unsigned int reservedpages = 0, freepages = 0;
97 unsigned long tmp;
98 unsigned long start_mem = memory_start;
99 unsigned long end_mem = memory_end;
100
101 end_mem &= PAGE_MASK;
102 high_memory = (void *)end_mem;
103
104 start_mem = PAGE_ALIGN(start_mem);
105 max_mapnr = num_physpages = MAP_NR(high_memory);
106 printk(KERN_DEBUG "Kernel managed physical pages: %lu\n", num_physpages);
107
108 /* This will put all memory onto the freelists. */
109 totalram_pages = free_all_bootmem();
110
111 reservedpages = 0;
112 for (tmp = 0; tmp < max_mapnr; tmp++)
113 if (PageReserved(pfn_to_page(tmp)))
114 reservedpages++;
115 freepages = max_mapnr - reservedpages;
116
117 /* do not count in kernel image between _rambase and _ramstart */
118 reservedpages -= (_ramstart - _rambase) >> PAGE_SHIFT;
119 #if (defined(CONFIG_BFIN_EXTMEM_ICACHEABLE) && ANOMALY_05000263)
120 reservedpages += (_ramend - memory_end - DMA_UNCACHED_REGION) >> PAGE_SHIFT;
121 #endif
122
123 codek = (_etext - _stext) >> 10;
124 initk = (__init_end - __init_begin) >> 10;
125 datak = ((_ramstart - _rambase) >> 10) - codek - initk;
126
127 printk(KERN_INFO
128 "Memory available: %luk/%luk RAM, "
129 "(%uk init code, %uk kernel code, %uk data, %uk dma, %uk reserved)\n",
130 (unsigned long) freepages << (PAGE_SHIFT-10), _ramend >> 10,
131 initk, codek, datak, DMA_UNCACHED_REGION >> 10, (reservedpages << (PAGE_SHIFT-10)));
132 }
133
free_init_pages(const char * what,unsigned long begin,unsigned long end)134 static void __init free_init_pages(const char *what, unsigned long begin, unsigned long end)
135 {
136 unsigned long addr;
137 /* next to check that the page we free is not a partial page */
138 for (addr = begin; addr + PAGE_SIZE <= end; addr += PAGE_SIZE) {
139 ClearPageReserved(virt_to_page(addr));
140 init_page_count(virt_to_page(addr));
141 free_page(addr);
142 totalram_pages++;
143 }
144 printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
145 }
146
147 #ifdef CONFIG_BLK_DEV_INITRD
free_initrd_mem(unsigned long start,unsigned long end)148 void __init free_initrd_mem(unsigned long start, unsigned long end)
149 {
150 #ifndef CONFIG_MPU
151 free_init_pages("initrd memory", start, end);
152 #endif
153 }
154 #endif
155
free_initmem(void)156 void __init_refok free_initmem(void)
157 {
158 #if defined CONFIG_RAMKERNEL && !defined CONFIG_MPU
159 free_init_pages("unused kernel memory",
160 (unsigned long)(&__init_begin),
161 (unsigned long)(&__init_end));
162
163 if (memory_start == (unsigned long)(&__init_end))
164 memory_start = (unsigned long)(&__init_begin);
165 #endif
166 }
167