atags_compat.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/kernel/atags_compat.c
*
* Copyright (C) 2001 Russell King
*
* We keep the old params compatibility cruft in one place (here)
* so we don't end up with lots of mess around other places.
*
* NOTE:
* The old struct param_struct is deprecated, but it will be kept in
* the kernel for 5 years from now (2001). This will allow boot loaders
* to convert to the new struct tag way.
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <asm/setup.h>
#include <asm/mach-types.h>
#include <asm/page.h>
#include <asm/mach/arch.h>
#include "atags.h"
/*
* Usage:
* - do not go blindly adding fields, add them at the end
* - when adding fields, don't rely on the address until
* a patch from me has been released
* - unused fields should be zero (for future expansion)
* - this structure is relatively short-lived - only
* guaranteed to contain useful data in setup_arch()
*
* This is the old deprecated way to pass parameters to the kernel
*/
struct param_struct {
union {
struct {
unsigned long page_size; /* 0 */
unsigned long nr_pages; /* 4 */
unsigned long ramdisk_size; /* 8 */
unsigned long flags; /* 12 */
#define FLAG_READONLY 1
#define FLAG_RDLOAD 4
#define FLAG_RDPROMPT 8
unsigned long rootdev; /* 16 */
unsigned long video_num_cols; /* 20 */
unsigned long video_num_rows; /* 24 */
unsigned long video_x; /* 28 */
unsigned long video_y; /* 32 */
unsigned long memc_control_reg; /* 36 */
unsigned char sounddefault; /* 40 */
unsigned char adfsdrives; /* 41 */
unsigned char bytes_per_char_h; /* 42 */
unsigned char bytes_per_char_v; /* 43 */
unsigned long pages_in_bank[4]; /* 44 */
unsigned long pages_in_vram; /* 60 */
unsigned long initrd_start; /* 64 */
unsigned long initrd_size; /* 68 */
unsigned long rd_start; /* 72 */
unsigned long system_rev; /* 76 */
unsigned long system_serial_low; /* 80 */
unsigned long system_serial_high; /* 84 */
unsigned long mem_fclk_21285; /* 88 */
} s;
char unused[256];
} u1;
union {
char paths[8][128];
struct {
unsigned long magic;
char n[1024 - sizeof(unsigned long)];
} s;
} u2;
char commandline[COMMAND_LINE_SIZE];
};
static struct tag * __init memtag(struct tag *tag, unsigned long start, unsigned long size)
{
tag = tag_next(tag);
tag->hdr.tag = ATAG_MEM;
tag->hdr.size = tag_size(tag_mem32);
tag->u.mem.size = size;
tag->u.mem.start = start;
return tag;
}
static void __init build_tag_list(struct param_struct *params, void *taglist)
{
struct tag *tag = taglist;
if (params->u1.s.page_size != PAGE_SIZE) {
pr_warn("Warning: bad configuration page, trying to continue\n");
return;
}
printk(KERN_DEBUG "Converting old-style param struct to taglist\n");
#ifdef CONFIG_ARCH_NETWINDER
if (params->u1.s.nr_pages != 0x02000 &&
params->u1.s.nr_pages != 0x04000 &&
params->u1.s.nr_pages != 0x08000 &&
params->u1.s.nr_pages != 0x10000) {
pr_warn("Warning: bad NeTTrom parameters detected, using defaults\n");
params->u1.s.nr_pages = 0x1000; /* 16MB */
params->u1.s.ramdisk_size = 0;
params->u1.s.flags = FLAG_READONLY;
params->u1.s.initrd_start = 0;
params->u1.s.initrd_size = 0;
params->u1.s.rd_start = 0;
}
#endif
tag->hdr.tag = ATAG_CORE;
tag->hdr.size = tag_size(tag_core);
tag->u.core.flags = params->u1.s.flags & FLAG_READONLY;
tag->u.core.pagesize = params->u1.s.page_size;
tag->u.core.rootdev = params->u1.s.rootdev;
tag = tag_next(tag);
tag->hdr.tag = ATAG_RAMDISK;
tag->hdr.size = tag_size(tag_ramdisk);
tag->u.ramdisk.flags = (params->u1.s.flags & FLAG_RDLOAD ? 1 : 0) |
(params->u1.s.flags & FLAG_RDPROMPT ? 2 : 0);
tag->u.ramdisk.size = params->u1.s.ramdisk_size;
tag->u.ramdisk.start = params->u1.s.rd_start;
tag = tag_next(tag);
tag->hdr.tag = ATAG_INITRD;
tag->hdr.size = tag_size(tag_initrd);
tag->u.initrd.start = params->u1.s.initrd_start;
tag->u.initrd.size = params->u1.s.initrd_size;
tag = tag_next(tag);
tag->hdr.tag = ATAG_SERIAL;
tag->hdr.size = tag_size(tag_serialnr);
tag->u.serialnr.low = params->u1.s.system_serial_low;
tag->u.serialnr.high = params->u1.s.system_serial_high;
tag = tag_next(tag);
tag->hdr.tag = ATAG_REVISION;
tag->hdr.size = tag_size(tag_revision);
tag->u.revision.rev = params->u1.s.system_rev;
#ifdef CONFIG_ARCH_ACORN
if (machine_is_riscpc()) {
int i;
for (i = 0; i < 4; i++)
tag = memtag(tag, PHYS_OFFSET + (i << 26),
params->u1.s.pages_in_bank[i] * PAGE_SIZE);
} else
#endif
tag = memtag(tag, PHYS_OFFSET, params->u1.s.nr_pages * PAGE_SIZE);
#ifdef CONFIG_FOOTBRIDGE
if (params->u1.s.mem_fclk_21285) {
tag = tag_next(tag);
tag->hdr.tag = ATAG_MEMCLK;
tag->hdr.size = tag_size(tag_memclk);
tag->u.memclk.fmemclk = params->u1.s.mem_fclk_21285;
}
#endif
#ifdef CONFIG_ARCH_EBSA285
if (machine_is_ebsa285()) {
tag = tag_next(tag);
tag->hdr.tag = ATAG_VIDEOTEXT;
tag->hdr.size = tag_size(tag_videotext);
tag->u.videotext.x = params->u1.s.video_x;
tag->u.videotext.y = params->u1.s.video_y;
tag->u.videotext.video_page = 0;
tag->u.videotext.video_mode = 0;
tag->u.videotext.video_cols = params->u1.s.video_num_cols;
tag->u.videotext.video_ega_bx = 0;
tag->u.videotext.video_lines = params->u1.s.video_num_rows;
tag->u.videotext.video_isvga = 1;
tag->u.videotext.video_points = 8;
}
#endif
#ifdef CONFIG_ARCH_ACORN
tag = tag_next(tag);
tag->hdr.tag = ATAG_ACORN;
tag->hdr.size = tag_size(tag_acorn);
tag->u.acorn.memc_control_reg = params->u1.s.memc_control_reg;
tag->u.acorn.vram_pages = params->u1.s.pages_in_vram;
tag->u.acorn.sounddefault = params->u1.s.sounddefault;
tag->u.acorn.adfsdrives = params->u1.s.adfsdrives;
#endif
tag = tag_next(tag);
tag->hdr.tag = ATAG_CMDLINE;
tag->hdr.size = (strlen(params->commandline) + 3 +
sizeof(struct tag_header)) >> 2;
strcpy(tag->u.cmdline.cmdline, params->commandline);
tag = tag_next(tag);
tag->hdr.tag = ATAG_NONE;
tag->hdr.size = 0;
memmove(params, taglist, ((int)tag) - ((int)taglist) +
sizeof(struct tag_header));
}
void __init convert_to_tag_list(struct tag *tags)
{
struct param_struct *params = (struct param_struct *)tags;
build_tag_list(params, ¶ms->u2);
}