From aa783b6fd60b3844e199b1c2d2f4068f3caa1358 Mon Sep 17 00:00:00 2001
From: Nicolas Pitre <nicolas.pitre@linaro.org>
Date: Sat, 1 Sep 2012 03:00:15 +0100
Subject: ARM: 7505/1: split out ATAGS parsing

Make ATAGS parsing into a source file of its own, namely atags_parse.c.
Also rename compat.c to atags_compat.c to make it clearer what it is
about.  Same for atags.c which is now atags_proc.c. Gather all the atags
function declarations into a common atags.h.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
 arch/arm/kernel/Makefile       |   6 +-
 arch/arm/kernel/atags.c        |  83 --------------
 arch/arm/kernel/atags.h        |   3 +
 arch/arm/kernel/atags_compat.c | 219 +++++++++++++++++++++++++++++++++++++
 arch/arm/kernel/atags_parse.c  | 238 +++++++++++++++++++++++++++++++++++++++++
 arch/arm/kernel/atags_proc.c   |  83 ++++++++++++++
 arch/arm/kernel/compat.c       | 219 -------------------------------------
 arch/arm/kernel/compat.h       |  11 --
 arch/arm/kernel/setup.c        | 236 +---------------------------------------
 9 files changed, 547 insertions(+), 551 deletions(-)
 delete mode 100644 arch/arm/kernel/atags.c
 create mode 100644 arch/arm/kernel/atags_compat.c
 create mode 100644 arch/arm/kernel/atags_parse.c
 create mode 100644 arch/arm/kernel/atags_proc.c
 delete mode 100644 arch/arm/kernel/compat.c
 delete mode 100644 arch/arm/kernel/compat.h

diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 7ad2d5cf7008..086c9d3bc360 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -15,11 +15,11 @@ CFLAGS_REMOVE_return_address.o = -pg
 
 # Object file lists.
 
-obj-y		:= elf.o entry-armv.o entry-common.o irq.o opcodes.o \
+obj-y		:= atags_parse.o elf.o entry-armv.o entry-common.o irq.o opcodes.o \
 		   process.o ptrace.o return_address.o sched_clock.o \
 		   setup.o signal.o stacktrace.o sys_arm.o time.o traps.o
 
-obj-$(CONFIG_DEPRECATED_PARAM_STRUCT) += compat.o
+obj-$(CONFIG_DEPRECATED_PARAM_STRUCT) += atags_compat.o
 
 obj-$(CONFIG_LEDS)		+= leds.o
 obj-$(CONFIG_OC_ETM)		+= etm.o
@@ -52,7 +52,7 @@ test-kprobes-objs		+= kprobes-test-thumb.o
 else
 test-kprobes-objs		+= kprobes-test-arm.o
 endif
-obj-$(CONFIG_ATAGS_PROC)	+= atags.o
+obj-$(CONFIG_ATAGS_PROC)	+= atags_proc.o
 obj-$(CONFIG_OABI_COMPAT)	+= sys_oabi-compat.o
 obj-$(CONFIG_ARM_THUMBEE)	+= thumbee.o
 obj-$(CONFIG_KGDB)		+= kgdb.o
diff --git a/arch/arm/kernel/atags.c b/arch/arm/kernel/atags.c
deleted file mode 100644
index 42a1a1415fa6..000000000000
--- a/arch/arm/kernel/atags.c
+++ /dev/null
@@ -1,83 +0,0 @@
-#include <linux/slab.h>
-#include <linux/proc_fs.h>
-#include <asm/setup.h>
-#include <asm/types.h>
-#include <asm/page.h>
-
-struct buffer {
-	size_t size;
-	char data[];
-};
-
-static int
-read_buffer(char* page, char** start, off_t off, int count,
-	int* eof, void* data)
-{
-	struct buffer *buffer = (struct buffer *)data;
-
-	if (off >= buffer->size) {
-		*eof = 1;
-		return 0;
-	}
-
-	count = min((int) (buffer->size - off), count);
-
-	memcpy(page, &buffer->data[off], count);
-
-	return count;
-}
-
-#define BOOT_PARAMS_SIZE 1536
-static char __initdata atags_copy[BOOT_PARAMS_SIZE];
-
-void __init save_atags(const struct tag *tags)
-{
-	memcpy(atags_copy, tags, sizeof(atags_copy));
-}
-
-static int __init init_atags_procfs(void)
-{
-	/*
-	 * This cannot go into save_atags() because kmalloc and proc don't work
-	 * yet when it is called.
-	 */
-	struct proc_dir_entry *tags_entry;
-	struct tag *tag = (struct tag *)atags_copy;
-	struct buffer *b;
-	size_t size;
-
-	if (tag->hdr.tag != ATAG_CORE) {
-		printk(KERN_INFO "No ATAGs?");
-		return -EINVAL;
-	}
-
-	for (; tag->hdr.size; tag = tag_next(tag))
-		;
-
-	/* include the terminating ATAG_NONE */
-	size = (char *)tag - atags_copy + sizeof(struct tag_header);
-
-	WARN_ON(tag->hdr.tag != ATAG_NONE);
-
-	b = kmalloc(sizeof(*b) + size, GFP_KERNEL);
-	if (!b)
-		goto nomem;
-
-	b->size = size;
-	memcpy(b->data, atags_copy, size);
-
-	tags_entry = create_proc_read_entry("atags", 0400,
-			NULL, read_buffer, b);
-
-	if (!tags_entry)
-		goto nomem;
-
-	return 0;
-
-nomem:
-	kfree(b);
-	printk(KERN_ERR "Exporting ATAGs: not enough memory\n");
-
-	return -ENOMEM;
-}
-arch_initcall(init_atags_procfs);
diff --git a/arch/arm/kernel/atags.h b/arch/arm/kernel/atags.h
index e5f028d214a1..a888fdd381b5 100644
--- a/arch/arm/kernel/atags.h
+++ b/arch/arm/kernel/atags.h
@@ -3,3 +3,6 @@ extern void save_atags(struct tag *tags);
 #else
 static inline void save_atags(struct tag *tags) { }
 #endif
+
+void convert_to_tag_list(struct tag *tags);
+struct machine_desc *setup_machine_tags(phys_addr_t __atags_pointer, unsigned int machine_nr);
diff --git a/arch/arm/kernel/atags_compat.c b/arch/arm/kernel/atags_compat.c
new file mode 100644
index 000000000000..5236ad38f417
--- /dev/null
+++ b/arch/arm/kernel/atags_compat.c
@@ -0,0 +1,219 @@
+/*
+ *  linux/arch/arm/kernel/atags_compat.c
+ *
+ *  Copyright (C) 2001 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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) {
+		printk(KERN_WARNING "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) {
+		printk(KERN_WARNING "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, &params->u2);
+}
diff --git a/arch/arm/kernel/atags_parse.c b/arch/arm/kernel/atags_parse.c
new file mode 100644
index 000000000000..14512e6931d8
--- /dev/null
+++ b/arch/arm/kernel/atags_parse.c
@@ -0,0 +1,238 @@
+/*
+ * Tag parsing.
+ *
+ * Copyright (C) 1995-2001 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/*
+ * This is the traditional way of passing data to the kernel at boot time.  Rather
+ * than passing a fixed inflexible structure to the kernel, we pass a list
+ * of variable-sized tags to the kernel.  The first tag must be a ATAG_CORE
+ * tag for the list to be recognised (to distinguish the tagged list from
+ * a param_struct).  The list is terminated with a zero-length tag (this tag
+ * is not parsed in any way).
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/root_dev.h>
+#include <linux/screen_info.h>
+
+#include <asm/setup.h>
+#include <asm/system_info.h>
+#include <asm/page.h>
+#include <asm/mach/arch.h>
+
+#include "atags.h"
+
+static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
+
+#ifndef MEM_SIZE
+#define MEM_SIZE	(16*1024*1024)
+#endif
+
+static struct {
+	struct tag_header hdr1;
+	struct tag_core   core;
+	struct tag_header hdr2;
+	struct tag_mem32  mem;
+	struct tag_header hdr3;
+} default_tags __initdata = {
+	{ tag_size(tag_core), ATAG_CORE },
+	{ 1, PAGE_SIZE, 0xff },
+	{ tag_size(tag_mem32), ATAG_MEM },
+	{ MEM_SIZE },
+	{ 0, ATAG_NONE }
+};
+
+static int __init parse_tag_core(const struct tag *tag)
+{
+	if (tag->hdr.size > 2) {
+		if ((tag->u.core.flags & 1) == 0)
+			root_mountflags &= ~MS_RDONLY;
+		ROOT_DEV = old_decode_dev(tag->u.core.rootdev);
+	}
+	return 0;
+}
+
+__tagtable(ATAG_CORE, parse_tag_core);
+
+static int __init parse_tag_mem32(const struct tag *tag)
+{
+	return arm_add_memory(tag->u.mem.start, tag->u.mem.size);
+}
+
+__tagtable(ATAG_MEM, parse_tag_mem32);
+
+#if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
+static int __init parse_tag_videotext(const struct tag *tag)
+{
+	screen_info.orig_x            = tag->u.videotext.x;
+	screen_info.orig_y            = tag->u.videotext.y;
+	screen_info.orig_video_page   = tag->u.videotext.video_page;
+	screen_info.orig_video_mode   = tag->u.videotext.video_mode;
+	screen_info.orig_video_cols   = tag->u.videotext.video_cols;
+	screen_info.orig_video_ega_bx = tag->u.videotext.video_ega_bx;
+	screen_info.orig_video_lines  = tag->u.videotext.video_lines;
+	screen_info.orig_video_isVGA  = tag->u.videotext.video_isvga;
+	screen_info.orig_video_points = tag->u.videotext.video_points;
+	return 0;
+}
+
+__tagtable(ATAG_VIDEOTEXT, parse_tag_videotext);
+#endif
+
+#ifdef CONFIG_BLK_DEV_RAM
+static int __init parse_tag_ramdisk(const struct tag *tag)
+{
+	extern int rd_size, rd_image_start, rd_prompt, rd_doload;
+
+	rd_image_start = tag->u.ramdisk.start;
+	rd_doload = (tag->u.ramdisk.flags & 1) == 0;
+	rd_prompt = (tag->u.ramdisk.flags & 2) == 0;
+
+	if (tag->u.ramdisk.size)
+		rd_size = tag->u.ramdisk.size;
+
+	return 0;
+}
+
+__tagtable(ATAG_RAMDISK, parse_tag_ramdisk);
+#endif
+
+static int __init parse_tag_serialnr(const struct tag *tag)
+{
+	system_serial_low = tag->u.serialnr.low;
+	system_serial_high = tag->u.serialnr.high;
+	return 0;
+}
+
+__tagtable(ATAG_SERIAL, parse_tag_serialnr);
+
+static int __init parse_tag_revision(const struct tag *tag)
+{
+	system_rev = tag->u.revision.rev;
+	return 0;
+}
+
+__tagtable(ATAG_REVISION, parse_tag_revision);
+
+static int __init parse_tag_cmdline(const struct tag *tag)
+{
+#if defined(CONFIG_CMDLINE_EXTEND)
+	strlcat(default_command_line, " ", COMMAND_LINE_SIZE);
+	strlcat(default_command_line, tag->u.cmdline.cmdline,
+		COMMAND_LINE_SIZE);
+#elif defined(CONFIG_CMDLINE_FORCE)
+	pr_warning("Ignoring tag cmdline (using the default kernel command line)\n");
+#else
+	strlcpy(default_command_line, tag->u.cmdline.cmdline,
+		COMMAND_LINE_SIZE);
+#endif
+	return 0;
+}
+
+__tagtable(ATAG_CMDLINE, parse_tag_cmdline);
+
+/*
+ * Scan the tag table for this tag, and call its parse function.
+ * The tag table is built by the linker from all the __tagtable
+ * declarations.
+ */
+static int __init parse_tag(const struct tag *tag)
+{
+	extern struct tagtable __tagtable_begin, __tagtable_end;
+	struct tagtable *t;
+
+	for (t = &__tagtable_begin; t < &__tagtable_end; t++)
+		if (tag->hdr.tag == t->tag) {
+			t->parse(tag);
+			break;
+		}
+
+	return t < &__tagtable_end;
+}
+
+/*
+ * Parse all tags in the list, checking both the global and architecture
+ * specific tag tables.
+ */
+static void __init parse_tags(const struct tag *t)
+{
+	for (; t->hdr.size; t = tag_next(t))
+		if (!parse_tag(t))
+			printk(KERN_WARNING
+				"Ignoring unrecognised tag 0x%08x\n",
+				t->hdr.tag);
+}
+
+static void __init squash_mem_tags(struct tag *tag)
+{
+	for (; tag->hdr.size; tag = tag_next(tag))
+		if (tag->hdr.tag == ATAG_MEM)
+			tag->hdr.tag = ATAG_NONE;
+}
+
+struct machine_desc * __init setup_machine_tags(phys_addr_t __atags_pointer,
+						unsigned int machine_nr)
+{
+	struct tag *tags = (struct tag *)&default_tags;
+	struct machine_desc *mdesc = NULL, *p;
+	char *from = default_command_line;
+
+	default_tags.mem.start = PHYS_OFFSET;
+
+	/*
+	 * locate machine in the list of supported machines.
+	 */
+	for_each_machine_desc(p)
+		if (machine_nr == p->nr) {
+			printk("Machine: %s\n", p->name);
+			mdesc = p;
+			break;
+		}
+
+	if (!mdesc) {
+		early_print("\nError: unrecognized/unsupported machine ID"
+			    " (r1 = 0x%08x).\n\n", machine_nr);
+		dump_machine_table(); /* does not return */
+	}
+
+	if (__atags_pointer)
+		tags = phys_to_virt(__atags_pointer);
+	else if (mdesc->atag_offset)
+		tags = (void *)(PAGE_OFFSET + mdesc->atag_offset);
+
+#if defined(CONFIG_DEPRECATED_PARAM_STRUCT)
+	/*
+	 * If we have the old style parameters, convert them to
+	 * a tag list.
+	 */
+	if (tags->hdr.tag != ATAG_CORE)
+		convert_to_tag_list(tags);
+#endif
+	if (tags->hdr.tag != ATAG_CORE) {
+		early_print("Warning: Neither atags nor dtb found\n");
+		tags = (struct tag *)&default_tags;
+	}
+
+	if (mdesc->fixup)
+		mdesc->fixup(tags, &from, &meminfo);
+
+	if (tags->hdr.tag == ATAG_CORE) {
+		if (meminfo.nr_banks != 0)
+			squash_mem_tags(tags);
+		save_atags(tags);
+		parse_tags(tags);
+	}
+
+	/* parse_early_param needs a boot_command_line */
+	strlcpy(boot_command_line, from, COMMAND_LINE_SIZE);
+
+	return mdesc;
+}
diff --git a/arch/arm/kernel/atags_proc.c b/arch/arm/kernel/atags_proc.c
new file mode 100644
index 000000000000..42a1a1415fa6
--- /dev/null
+++ b/arch/arm/kernel/atags_proc.c
@@ -0,0 +1,83 @@
+#include <linux/slab.h>
+#include <linux/proc_fs.h>
+#include <asm/setup.h>
+#include <asm/types.h>
+#include <asm/page.h>
+
+struct buffer {
+	size_t size;
+	char data[];
+};
+
+static int
+read_buffer(char* page, char** start, off_t off, int count,
+	int* eof, void* data)
+{
+	struct buffer *buffer = (struct buffer *)data;
+
+	if (off >= buffer->size) {
+		*eof = 1;
+		return 0;
+	}
+
+	count = min((int) (buffer->size - off), count);
+
+	memcpy(page, &buffer->data[off], count);
+
+	return count;
+}
+
+#define BOOT_PARAMS_SIZE 1536
+static char __initdata atags_copy[BOOT_PARAMS_SIZE];
+
+void __init save_atags(const struct tag *tags)
+{
+	memcpy(atags_copy, tags, sizeof(atags_copy));
+}
+
+static int __init init_atags_procfs(void)
+{
+	/*
+	 * This cannot go into save_atags() because kmalloc and proc don't work
+	 * yet when it is called.
+	 */
+	struct proc_dir_entry *tags_entry;
+	struct tag *tag = (struct tag *)atags_copy;
+	struct buffer *b;
+	size_t size;
+
+	if (tag->hdr.tag != ATAG_CORE) {
+		printk(KERN_INFO "No ATAGs?");
+		return -EINVAL;
+	}
+
+	for (; tag->hdr.size; tag = tag_next(tag))
+		;
+
+	/* include the terminating ATAG_NONE */
+	size = (char *)tag - atags_copy + sizeof(struct tag_header);
+
+	WARN_ON(tag->hdr.tag != ATAG_NONE);
+
+	b = kmalloc(sizeof(*b) + size, GFP_KERNEL);
+	if (!b)
+		goto nomem;
+
+	b->size = size;
+	memcpy(b->data, atags_copy, size);
+
+	tags_entry = create_proc_read_entry("atags", 0400,
+			NULL, read_buffer, b);
+
+	if (!tags_entry)
+		goto nomem;
+
+	return 0;
+
+nomem:
+	kfree(b);
+	printk(KERN_ERR "Exporting ATAGs: not enough memory\n");
+
+	return -ENOMEM;
+}
+arch_initcall(init_atags_procfs);
diff --git a/arch/arm/kernel/compat.c b/arch/arm/kernel/compat.c
deleted file mode 100644
index 925652318b8b..000000000000
--- a/arch/arm/kernel/compat.c
+++ /dev/null
@@ -1,219 +0,0 @@
-/*
- *  linux/arch/arm/kernel/compat.c
- *
- *  Copyright (C) 2001 Russell King
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * 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 "compat.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) {
-		printk(KERN_WARNING "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) {
-		printk(KERN_WARNING "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, &params->u2);
-}
diff --git a/arch/arm/kernel/compat.h b/arch/arm/kernel/compat.h
deleted file mode 100644
index 39264ab1b9c6..000000000000
--- a/arch/arm/kernel/compat.h
+++ /dev/null
@@ -1,11 +0,0 @@
-/*
- *  linux/arch/arm/kernel/compat.h
- *
- *  Copyright (C) 2001 Russell King
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
-*/
-
-extern void convert_to_tag_list(struct tag *tags);
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index a81dcecc7343..0785472460a8 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -21,11 +21,9 @@
 #include <linux/init.h>
 #include <linux/kexec.h>
 #include <linux/of_fdt.h>
-#include <linux/root_dev.h>
 #include <linux/cpu.h>
 #include <linux/interrupt.h>
 #include <linux/smp.h>
-#include <linux/fs.h>
 #include <linux/proc_fs.h>
 #include <linux/memblock.h>
 #include <linux/bug.h>
@@ -56,15 +54,9 @@
 #include <asm/unwind.h>
 #include <asm/memblock.h>
 
-#if defined(CONFIG_DEPRECATED_PARAM_STRUCT)
-#include "compat.h"
-#endif
 #include "atags.h"
 #include "tcm.h"
 
-#ifndef MEM_SIZE
-#define MEM_SIZE	(16*1024*1024)
-#endif
 
 #if defined(CONFIG_FPE_NWFPE) || defined(CONFIG_FPE_FASTFPE)
 char fpe_type[8];
@@ -145,7 +137,6 @@ static const char *machine_name;
 static char __initdata cmd_line[COMMAND_LINE_SIZE];
 struct machine_desc *machine_desc __initdata;
 
-static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
 static union { char c[4]; unsigned long l; } endian_test __initdata = { { 'l', '?', '?', 'b' } };
 #define ENDIANNESS ((char)endian_test.l)
 
@@ -583,21 +574,6 @@ static int __init early_mem(char *p)
 }
 early_param("mem", early_mem);
 
-static void __init
-setup_ramdisk(int doload, int prompt, int image_start, unsigned int rd_sz)
-{
-#ifdef CONFIG_BLK_DEV_RAM
-	extern int rd_size, rd_image_start, rd_prompt, rd_doload;
-
-	rd_image_start = image_start;
-	rd_prompt = prompt;
-	rd_doload = doload;
-
-	if (rd_sz)
-		rd_size = rd_sz;
-#endif
-}
-
 static void __init request_standard_resources(struct machine_desc *mdesc)
 {
 	struct memblock_region *region;
@@ -643,35 +619,6 @@ static void __init request_standard_resources(struct machine_desc *mdesc)
 		request_resource(&ioport_resource, &lp2);
 }
 
-/*
- *  Tag parsing.
- *
- * This is the new way of passing data to the kernel at boot time.  Rather
- * than passing a fixed inflexible structure to the kernel, we pass a list
- * of variable-sized tags to the kernel.  The first tag must be a ATAG_CORE
- * tag for the list to be recognised (to distinguish the tagged list from
- * a param_struct).  The list is terminated with a zero-length tag (this tag
- * is not parsed in any way).
- */
-static int __init parse_tag_core(const struct tag *tag)
-{
-	if (tag->hdr.size > 2) {
-		if ((tag->u.core.flags & 1) == 0)
-			root_mountflags &= ~MS_RDONLY;
-		ROOT_DEV = old_decode_dev(tag->u.core.rootdev);
-	}
-	return 0;
-}
-
-__tagtable(ATAG_CORE, parse_tag_core);
-
-static int __init parse_tag_mem32(const struct tag *tag)
-{
-	return arm_add_memory(tag->u.mem.start, tag->u.mem.size);
-}
-
-__tagtable(ATAG_MEM, parse_tag_mem32);
-
 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
 struct screen_info screen_info = {
  .orig_video_lines	= 30,
@@ -681,117 +628,8 @@ struct screen_info screen_info = {
  .orig_video_isVGA	= 1,
  .orig_video_points	= 8
 };
-
-static int __init parse_tag_videotext(const struct tag *tag)
-{
-	screen_info.orig_x            = tag->u.videotext.x;
-	screen_info.orig_y            = tag->u.videotext.y;
-	screen_info.orig_video_page   = tag->u.videotext.video_page;
-	screen_info.orig_video_mode   = tag->u.videotext.video_mode;
-	screen_info.orig_video_cols   = tag->u.videotext.video_cols;
-	screen_info.orig_video_ega_bx = tag->u.videotext.video_ega_bx;
-	screen_info.orig_video_lines  = tag->u.videotext.video_lines;
-	screen_info.orig_video_isVGA  = tag->u.videotext.video_isvga;
-	screen_info.orig_video_points = tag->u.videotext.video_points;
-	return 0;
-}
-
-__tagtable(ATAG_VIDEOTEXT, parse_tag_videotext);
 #endif
 
-static int __init parse_tag_ramdisk(const struct tag *tag)
-{
-	setup_ramdisk((tag->u.ramdisk.flags & 1) == 0,
-		      (tag->u.ramdisk.flags & 2) == 0,
-		      tag->u.ramdisk.start, tag->u.ramdisk.size);
-	return 0;
-}
-
-__tagtable(ATAG_RAMDISK, parse_tag_ramdisk);
-
-static int __init parse_tag_serialnr(const struct tag *tag)
-{
-	system_serial_low = tag->u.serialnr.low;
-	system_serial_high = tag->u.serialnr.high;
-	return 0;
-}
-
-__tagtable(ATAG_SERIAL, parse_tag_serialnr);
-
-static int __init parse_tag_revision(const struct tag *tag)
-{
-	system_rev = tag->u.revision.rev;
-	return 0;
-}
-
-__tagtable(ATAG_REVISION, parse_tag_revision);
-
-static int __init parse_tag_cmdline(const struct tag *tag)
-{
-#if defined(CONFIG_CMDLINE_EXTEND)
-	strlcat(default_command_line, " ", COMMAND_LINE_SIZE);
-	strlcat(default_command_line, tag->u.cmdline.cmdline,
-		COMMAND_LINE_SIZE);
-#elif defined(CONFIG_CMDLINE_FORCE)
-	pr_warning("Ignoring tag cmdline (using the default kernel command line)\n");
-#else
-	strlcpy(default_command_line, tag->u.cmdline.cmdline,
-		COMMAND_LINE_SIZE);
-#endif
-	return 0;
-}
-
-__tagtable(ATAG_CMDLINE, parse_tag_cmdline);
-
-/*
- * Scan the tag table for this tag, and call its parse function.
- * The tag table is built by the linker from all the __tagtable
- * declarations.
- */
-static int __init parse_tag(const struct tag *tag)
-{
-	extern struct tagtable __tagtable_begin, __tagtable_end;
-	struct tagtable *t;
-
-	for (t = &__tagtable_begin; t < &__tagtable_end; t++)
-		if (tag->hdr.tag == t->tag) {
-			t->parse(tag);
-			break;
-		}
-
-	return t < &__tagtable_end;
-}
-
-/*
- * Parse all tags in the list, checking both the global and architecture
- * specific tag tables.
- */
-static void __init parse_tags(const struct tag *t)
-{
-	for (; t->hdr.size; t = tag_next(t))
-		if (!parse_tag(t))
-			printk(KERN_WARNING
-				"Ignoring unrecognised tag 0x%08x\n",
-				t->hdr.tag);
-}
-
-/*
- * This holds our defaults.
- */
-static struct init_tags {
-	struct tag_header hdr1;
-	struct tag_core   core;
-	struct tag_header hdr2;
-	struct tag_mem32  mem;
-	struct tag_header hdr3;
-} init_tags __initdata = {
-	{ tag_size(tag_core), ATAG_CORE },
-	{ 1, PAGE_SIZE, 0xff },
-	{ tag_size(tag_mem32), ATAG_MEM },
-	{ MEM_SIZE },
-	{ 0, ATAG_NONE }
-};
-
 static int __init customize_machine(void)
 {
 	/* customizes platform devices, or adds new ones */
@@ -858,78 +696,6 @@ static void __init reserve_crashkernel(void)
 static inline void reserve_crashkernel(void) {}
 #endif /* CONFIG_KEXEC */
 
-static void __init squash_mem_tags(struct tag *tag)
-{
-	for (; tag->hdr.size; tag = tag_next(tag))
-		if (tag->hdr.tag == ATAG_MEM)
-			tag->hdr.tag = ATAG_NONE;
-}
-
-static struct machine_desc * __init setup_machine_tags(unsigned int nr)
-{
-	struct tag *tags = (struct tag *)&init_tags;
-	struct machine_desc *mdesc = NULL, *p;
-	char *from = default_command_line;
-
-	init_tags.mem.start = PHYS_OFFSET;
-
-	/*
-	 * locate machine in the list of supported machines.
-	 */
-	for_each_machine_desc(p)
-		if (nr == p->nr) {
-			printk("Machine: %s\n", p->name);
-			mdesc = p;
-			break;
-		}
-
-	if (!mdesc) {
-		early_print("\nError: unrecognized/unsupported machine ID"
-			" (r1 = 0x%08x).\n\n", nr);
-		dump_machine_table(); /* does not return */
-	}
-
-	if (__atags_pointer)
-		tags = phys_to_virt(__atags_pointer);
-	else if (mdesc->atag_offset)
-		tags = (void *)(PAGE_OFFSET + mdesc->atag_offset);
-
-#if defined(CONFIG_DEPRECATED_PARAM_STRUCT)
-	/*
-	 * If we have the old style parameters, convert them to
-	 * a tag list.
-	 */
-	if (tags->hdr.tag != ATAG_CORE)
-		convert_to_tag_list(tags);
-#endif
-
-	if (tags->hdr.tag != ATAG_CORE) {
-#if defined(CONFIG_OF)
-		/*
-		 * If CONFIG_OF is set, then assume this is a reasonably
-		 * modern system that should pass boot parameters
-		 */
-		early_print("Warning: Neither atags nor dtb found\n");
-#endif
-		tags = (struct tag *)&init_tags;
-	}
-
-	if (mdesc->fixup)
-		mdesc->fixup(tags, &from, &meminfo);
-
-	if (tags->hdr.tag == ATAG_CORE) {
-		if (meminfo.nr_banks != 0)
-			squash_mem_tags(tags);
-		save_atags(tags);
-		parse_tags(tags);
-	}
-
-	/* parse_early_param needs a boot_command_line */
-	strlcpy(boot_command_line, from, COMMAND_LINE_SIZE);
-
-	return mdesc;
-}
-
 static int __init meminfo_cmp(const void *_a, const void *_b)
 {
 	const struct membank *a = _a, *b = _b;
@@ -944,7 +710,7 @@ void __init setup_arch(char **cmdline_p)
 	setup_processor();
 	mdesc = setup_machine_fdt(__atags_pointer);
 	if (!mdesc)
-		mdesc = setup_machine_tags(machine_arch_type);
+		mdesc = setup_machine_tags(__atags_pointer, machine_arch_type);
 	machine_desc = mdesc;
 	machine_name = mdesc->name;
 
-- 
cgit