[PATCH 1/2] ARM: split out ATAGS parsing
Nicolas Pitre
nicolas.pitre at linaro.org
Thu Aug 30 17:10:07 EDT 2012
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 at linaro.org>
---
arch/arm/kernel/Makefile | 6 +-
arch/arm/kernel/atags.h | 3 +
arch/arm/kernel/{compat.c => atags_compat.c} | 4 +-
arch/arm/kernel/atags_parse.c | 238 +++++++++++++++++++++++++++
arch/arm/kernel/{atags.c => atags_proc.c} | 0
arch/arm/kernel/compat.h | 11 --
arch/arm/kernel/setup.c | 236 +-------------------------
7 files changed, 247 insertions(+), 251 deletions(-)
rename arch/arm/kernel/{compat.c => atags_compat.c} (99%)
create mode 100644 arch/arm/kernel/atags_parse.c
rename arch/arm/kernel/{atags.c => atags_proc.c} (100%)
delete mode 100644 arch/arm/kernel/compat.h
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 7ad2d5cf70..086c9d3bc3 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.h b/arch/arm/kernel/atags.h
index e5f028d214..a888fdd381 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/compat.c b/arch/arm/kernel/atags_compat.c
similarity index 99%
rename from arch/arm/kernel/compat.c
rename to arch/arm/kernel/atags_compat.c
index 925652318b..5236ad38f4 100644
--- a/arch/arm/kernel/compat.c
+++ b/arch/arm/kernel/atags_compat.c
@@ -1,5 +1,5 @@
/*
- * linux/arch/arm/kernel/compat.c
+ * linux/arch/arm/kernel/atags_compat.c
*
* Copyright (C) 2001 Russell King
*
@@ -26,7 +26,7 @@
#include <asm/mach/arch.h>
-#include "compat.h"
+#include "atags.h"
/*
* Usage:
diff --git a/arch/arm/kernel/atags_parse.c b/arch/arm/kernel/atags_parse.c
new file mode 100644
index 0000000000..18f13be99e
--- /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.c b/arch/arm/kernel/atags_proc.c
similarity index 100%
rename from arch/arm/kernel/atags.c
rename to arch/arm/kernel/atags_proc.c
diff --git a/arch/arm/kernel/compat.h b/arch/arm/kernel/compat.h
deleted file mode 100644
index 39264ab1b9..0000000000
--- 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 a81dcecc73..0785472460 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;
--
1.7.12.84.gefa6462
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