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