/spare/repo/netdev-2.6 branch 'ieee80211'
[linux-2.6] / arch / arm / kernel / compat.c
1 /*
2  *  linux/arch/arm/kernel/compat.c
3  *
4  *  Copyright (C) 2001 Russell King
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * We keep the old params compatibility cruft in one place (here)
11  * so we don't end up with lots of mess around other places.
12  *
13  * NOTE:
14  *  The old struct param_struct is deprecated, but it will be kept in
15  *  the kernel for 5 years from now (2001). This will allow boot loaders
16  *  to convert to the new struct tag way.
17  */
18 #include <linux/config.h>
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/string.h>
22 #include <linux/init.h>
23
24 #include <asm/setup.h>
25 #include <asm/mach-types.h>
26 #include <asm/page.h>
27
28 #include <asm/mach/arch.h>
29
30 /*
31  * Usage:
32  *  - do not go blindly adding fields, add them at the end
33  *  - when adding fields, don't rely on the address until
34  *    a patch from me has been released
35  *  - unused fields should be zero (for future expansion)
36  *  - this structure is relatively short-lived - only
37  *    guaranteed to contain useful data in setup_arch()
38  *
39  * This is the old deprecated way to pass parameters to the kernel
40  */
41 struct param_struct {
42     union {
43         struct {
44             unsigned long page_size;            /*  0 */
45             unsigned long nr_pages;             /*  4 */
46             unsigned long ramdisk_size;         /*  8 */
47             unsigned long flags;                /* 12 */
48 #define FLAG_READONLY   1
49 #define FLAG_RDLOAD     4
50 #define FLAG_RDPROMPT   8
51             unsigned long rootdev;              /* 16 */
52             unsigned long video_num_cols;       /* 20 */
53             unsigned long video_num_rows;       /* 24 */
54             unsigned long video_x;              /* 28 */
55             unsigned long video_y;              /* 32 */
56             unsigned long memc_control_reg;     /* 36 */
57             unsigned char sounddefault;         /* 40 */
58             unsigned char adfsdrives;           /* 41 */
59             unsigned char bytes_per_char_h;     /* 42 */
60             unsigned char bytes_per_char_v;     /* 43 */
61             unsigned long pages_in_bank[4];     /* 44 */
62             unsigned long pages_in_vram;        /* 60 */
63             unsigned long initrd_start;         /* 64 */
64             unsigned long initrd_size;          /* 68 */
65             unsigned long rd_start;             /* 72 */
66             unsigned long system_rev;           /* 76 */
67             unsigned long system_serial_low;    /* 80 */
68             unsigned long system_serial_high;   /* 84 */
69             unsigned long mem_fclk_21285;       /* 88 */
70         } s;
71         char unused[256];
72     } u1;
73     union {
74         char paths[8][128];
75         struct {
76             unsigned long magic;
77             char n[1024 - sizeof(unsigned long)];
78         } s;
79     } u2;
80     char commandline[COMMAND_LINE_SIZE];
81 };
82
83 static struct tag * __init memtag(struct tag *tag, unsigned long start, unsigned long size)
84 {
85         tag = tag_next(tag);
86         tag->hdr.tag = ATAG_MEM;
87         tag->hdr.size = tag_size(tag_mem32);
88         tag->u.mem.size = size;
89         tag->u.mem.start = start;
90
91         return tag;
92 }
93
94 static void __init build_tag_list(struct param_struct *params, void *taglist)
95 {
96         struct tag *tag = taglist;
97
98         if (params->u1.s.page_size != PAGE_SIZE) {
99                 printk(KERN_WARNING "Warning: bad configuration page, "
100                        "trying to continue\n");
101                 return;
102         }
103
104         printk(KERN_DEBUG "Converting old-style param struct to taglist\n");
105
106 #ifdef CONFIG_ARCH_NETWINDER
107         if (params->u1.s.nr_pages != 0x02000 &&
108             params->u1.s.nr_pages != 0x04000 &&
109             params->u1.s.nr_pages != 0x08000 &&
110             params->u1.s.nr_pages != 0x10000) {
111                 printk(KERN_WARNING "Warning: bad NeTTrom parameters "
112                        "detected, using defaults\n");
113
114                 params->u1.s.nr_pages = 0x1000; /* 16MB */
115                 params->u1.s.ramdisk_size = 0;
116                 params->u1.s.flags = FLAG_READONLY;
117                 params->u1.s.initrd_start = 0;
118                 params->u1.s.initrd_size = 0;
119                 params->u1.s.rd_start = 0;
120         }
121 #endif
122
123         tag->hdr.tag  = ATAG_CORE;
124         tag->hdr.size = tag_size(tag_core);
125         tag->u.core.flags = params->u1.s.flags & FLAG_READONLY;
126         tag->u.core.pagesize = params->u1.s.page_size;
127         tag->u.core.rootdev = params->u1.s.rootdev;
128
129         tag = tag_next(tag);
130         tag->hdr.tag = ATAG_RAMDISK;
131         tag->hdr.size = tag_size(tag_ramdisk);
132         tag->u.ramdisk.flags = (params->u1.s.flags & FLAG_RDLOAD ? 1 : 0) |
133                                (params->u1.s.flags & FLAG_RDPROMPT ? 2 : 0);
134         tag->u.ramdisk.size  = params->u1.s.ramdisk_size;
135         tag->u.ramdisk.start = params->u1.s.rd_start;
136
137         tag = tag_next(tag);
138         tag->hdr.tag = ATAG_INITRD;
139         tag->hdr.size = tag_size(tag_initrd);
140         tag->u.initrd.start = params->u1.s.initrd_start;
141         tag->u.initrd.size  = params->u1.s.initrd_size;
142
143         tag = tag_next(tag);
144         tag->hdr.tag = ATAG_SERIAL;
145         tag->hdr.size = tag_size(tag_serialnr);
146         tag->u.serialnr.low = params->u1.s.system_serial_low;
147         tag->u.serialnr.high = params->u1.s.system_serial_high;
148
149         tag = tag_next(tag);
150         tag->hdr.tag = ATAG_REVISION;
151         tag->hdr.size = tag_size(tag_revision);
152         tag->u.revision.rev = params->u1.s.system_rev;
153
154 #ifdef CONFIG_ARCH_ACORN
155         if (machine_is_riscpc()) {
156                 int i;
157                 for (i = 0; i < 4; i++)
158                         tag = memtag(tag, PHYS_OFFSET + (i << 26),
159                                  params->u1.s.pages_in_bank[i] * PAGE_SIZE);
160         } else
161 #endif
162         tag = memtag(tag, PHYS_OFFSET, params->u1.s.nr_pages * PAGE_SIZE);
163
164 #ifdef CONFIG_FOOTBRIDGE
165         if (params->u1.s.mem_fclk_21285) {
166                 tag = tag_next(tag);
167                 tag->hdr.tag = ATAG_MEMCLK;
168                 tag->hdr.size = tag_size(tag_memclk);
169                 tag->u.memclk.fmemclk = params->u1.s.mem_fclk_21285;
170         }
171 #endif
172
173 #ifdef CONFIG_ARCH_EBSA285
174         if (machine_is_ebsa285()) {
175                 tag = tag_next(tag);
176                 tag->hdr.tag = ATAG_VIDEOTEXT;
177                 tag->hdr.size = tag_size(tag_videotext);
178                 tag->u.videotext.x            = params->u1.s.video_x;
179                 tag->u.videotext.y            = params->u1.s.video_y;
180                 tag->u.videotext.video_page   = 0;
181                 tag->u.videotext.video_mode   = 0;
182                 tag->u.videotext.video_cols   = params->u1.s.video_num_cols;
183                 tag->u.videotext.video_ega_bx = 0;
184                 tag->u.videotext.video_lines  = params->u1.s.video_num_rows;
185                 tag->u.videotext.video_isvga  = 1;
186                 tag->u.videotext.video_points = 8;
187         }
188 #endif
189
190 #ifdef CONFIG_ARCH_ACORN
191         tag = tag_next(tag);
192         tag->hdr.tag = ATAG_ACORN;
193         tag->hdr.size = tag_size(tag_acorn);
194         tag->u.acorn.memc_control_reg = params->u1.s.memc_control_reg;
195         tag->u.acorn.vram_pages       = params->u1.s.pages_in_vram;
196         tag->u.acorn.sounddefault     = params->u1.s.sounddefault;
197         tag->u.acorn.adfsdrives       = params->u1.s.adfsdrives;
198 #endif
199
200         tag = tag_next(tag);
201         tag->hdr.tag = ATAG_CMDLINE;
202         tag->hdr.size = (strlen(params->commandline) + 3 +
203                          sizeof(struct tag_header)) >> 2;
204         strcpy(tag->u.cmdline.cmdline, params->commandline);
205
206         tag = tag_next(tag);
207         tag->hdr.tag = ATAG_NONE;
208         tag->hdr.size = 0;
209
210         memmove(params, taglist, ((int)tag) - ((int)taglist) +
211                                  sizeof(struct tag_header));
212 }
213
214 void __init convert_to_tag_list(struct tag *tags)
215 {
216         struct param_struct *params = (struct param_struct *)tags;
217         build_tag_list(params, &params->u2);
218 }
219
220 void __init squash_mem_tags(struct tag *tag)
221 {
222         for (; tag->hdr.size; tag = tag_next(tag))
223                 if (tag->hdr.tag == ATAG_MEM)
224                         tag->hdr.tag = ATAG_NONE;
225 }