3 * linux/arch/cris/kernel/setup.c
5 * Copyright (C) 1995 Linus Torvalds
6 * Copyright (c) 2001 Axis Communications AB
10 * This file handles the architecture-dependent parts of initialization
13 #include <linux/config.h>
14 #include <linux/init.h>
16 #include <linux/bootmem.h>
17 #include <asm/pgtable.h>
18 #include <linux/seq_file.h>
19 #include <linux/tty.h>
20 #include <linux/utsname.h>
21 #include <linux/pfn.h>
23 #include <asm/setup.h>
28 struct screen_info screen_info
;
30 extern int root_mountflags
;
31 extern char _etext
, _edata
, _end
;
33 char cris_command_line
[COMMAND_LINE_SIZE
] = { 0, };
35 extern const unsigned long text_start
, edata
; /* set by the linker script */
36 extern unsigned long dram_start
, dram_end
;
38 extern unsigned long romfs_start
, romfs_length
, romfs_in_flash
; /* from head.S */
40 extern void show_etrax_copyright(void); /* arch-vX/kernel/setup.c */
42 /* This mainly sets up the memory area, and can be really confusing.
44 * The physical DRAM is virtually mapped into dram_start to dram_end
45 * (usually c0000000 to c0000000 + DRAM size). The physical address is
46 * given by the macro __pa().
48 * In this DRAM, the kernel code and data is loaded, in the beginning.
49 * It really starts at c0004000 to make room for some special pages -
50 * the start address is text_start. The kernel data ends at _end. After
51 * this the ROM filesystem is appended (if there is any).
53 * Between this address and dram_end, we have RAM pages usable to the
54 * boot code and the system.
59 setup_arch(char **cmdline_p
)
61 extern void init_etrax_debug(void);
62 unsigned long bootmap_size
;
63 unsigned long start_pfn
, max_pfn
;
64 unsigned long memory_start
;
66 /* register an initial console printing routine for printk's */
70 /* we should really poll for DRAM size! */
72 high_memory
= &dram_end
;
74 if(romfs_in_flash
|| !romfs_length
) {
75 /* if we have the romfs in flash, or if there is no rom filesystem,
76 * our free area starts directly after the BSS
78 memory_start
= (unsigned long) &_end
;
80 /* otherwise the free area starts after the ROM filesystem */
81 printk("ROM fs in RAM, size %lu bytes\n", romfs_length
);
82 memory_start
= romfs_start
+ romfs_length
;
85 /* process 1's initial memory region is the kernel code/data */
87 init_mm
.start_code
= (unsigned long) &text_start
;
88 init_mm
.end_code
= (unsigned long) &_etext
;
89 init_mm
.end_data
= (unsigned long) &_edata
;
90 init_mm
.brk
= (unsigned long) &_end
;
92 /* min_low_pfn points to the start of DRAM, start_pfn points
93 * to the first DRAM pages after the kernel, and max_low_pfn
98 * partially used pages are not usable - thus
99 * we are rounding upwards:
102 start_pfn
= PFN_UP(memory_start
); /* usually c0000000 + kernel + romfs */
103 max_pfn
= PFN_DOWN((unsigned long)high_memory
); /* usually c0000000 + dram size */
106 * Initialize the boot-time allocator (start, end)
108 * We give it access to all our DRAM, but we could as well just have
109 * given it a small slice. No point in doing that though, unless we
110 * have non-contiguous memory and want the boot-stuff to be in, say,
113 * It will put a bitmap of the allocated pages in the beginning
114 * of the range we give it, but it won't mark the bitmaps pages
115 * as reserved. We have to do that ourselves below.
117 * We need to use init_bootmem_node instead of init_bootmem
118 * because our map starts at a quite high address (min_low_pfn).
121 max_low_pfn
= max_pfn
;
122 min_low_pfn
= PAGE_OFFSET
>> PAGE_SHIFT
;
124 bootmap_size
= init_bootmem_node(NODE_DATA(0), start_pfn
,
128 /* And free all memory not belonging to the kernel (addr, size) */
130 free_bootmem(PFN_PHYS(start_pfn
), PFN_PHYS(max_pfn
- start_pfn
));
133 * Reserve the bootmem bitmap itself as well. We do this in two
134 * steps (first step was init_bootmem()) because this catches
135 * the (very unlikely) case of us accidentally initializing the
136 * bootmem allocator with an invalid RAM area.
138 * Arguments are start, size
141 reserve_bootmem(PFN_PHYS(start_pfn
), bootmap_size
);
143 /* paging_init() sets up the MMU and marks all pages as reserved */
147 *cmdline_p
= cris_command_line
;
149 #ifdef CONFIG_ETRAX_CMDLINE
150 if (!strcmp(cris_command_line
, "")) {
151 strlcpy(cris_command_line
, CONFIG_ETRAX_CMDLINE
, COMMAND_LINE_SIZE
);
152 cris_command_line
[COMMAND_LINE_SIZE
- 1] = '\0';
156 /* Save command line for future references. */
157 memcpy(saved_command_line
, cris_command_line
, COMMAND_LINE_SIZE
);
158 saved_command_line
[COMMAND_LINE_SIZE
- 1] = '\0';
160 /* give credit for the CRIS port */
161 show_etrax_copyright();
164 strcpy(system_utsname
.machine
, cris_machine_name
);
167 static void *c_start(struct seq_file
*m
, loff_t
*pos
)
169 return *pos
< NR_CPUS
? (void *)(int)(*pos
+ 1): NULL
;
172 static void *c_next(struct seq_file
*m
, void *v
, loff_t
*pos
)
175 return c_start(m
, pos
);
178 static void c_stop(struct seq_file
*m
, void *v
)
182 extern int show_cpuinfo(struct seq_file
*m
, void *v
);
184 struct seq_operations cpuinfo_op
= {
188 .show
= show_cpuinfo
,