introduce K64BIT=y and backward compatibility ARCH={i386,x86_64} for x86

Signed-off-by Sam Ravnborg <[email protected]>

---
 README |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

README +0 -0

index 159912c..6622ba1 100644

This change allow us to use the new syntax:
make K64BIT={n,y} to select between 32 and 64 bit.

Signed-off-by Sam Ravnborg <[email protected]>

---
 arch/x86/Kconfig |   26 ++++++++------------------
 1 files changed, 8 insertions(+), 18 deletions(-)

arch/x86/Kconfig +0 -0

index 153c26c..0d86611 100644

arch/x86/Kconfig +2 -12

 config X86_32
-	bool "32 bit (former ARCH=i386)"
-	help
-	  This is Linux's home port.  Linux was originally native to the Intel
-	  386, and runs on all the later x86 processors including the Intel
-	  486, 586, Pentiums, and various instruction-set-compatible chips by
-	  AMD, Cyrix, and others.
+	def_bool !64BIT
 
 config X86_64
-	bool "64 bit (former ARCH=x86_64)"
-	help
-	  Port to the x86-64 architecture. x86-64 is a 64-bit extension to the
-	  classical 32-bit x86 architecture. For details see
-	  <http://www.x86-64.org/>.
-endchoice
+	def_bool 64BIT
 
 ### Arch settings

The variable K64BIT can now be used to select the
value of CONFIG_64BIT.

Hi,

Quoted 2 lines · Sam Ravnborg

The variable K64BIT can now be used to select the
value of CONFIG_64BIT.

Why not calling the environment variable CONFIG_64BIT, in preparation of the day when all CONFIG_ variables can be passed by environment variables?

Guillaume

What exactly are the use cases where someone would need this?

Hi Adrian,

Quoted 1 line

What exactly are the use cases where someone would need this?

Glad you asked. Today, when I want to recompile a kernel while changing a CONFIG_ option, I manually edit the .config, remove the appropriate line and then run make oldconfig. I'd like to be able to do: make oldconfig CONFIG_FOO=bar.

Also, when working on a specific feature of the kernel, I tend to install both a kernel with the CONFIG_ option set and one with the option unset. Scripts to do that can twiddle the .config file, but it would be more convenient if kbuild could avoid that.

As you see, I'm more interested in make oldconfig than make all*config.

Cheers.
Guillaume

Another important point is that users that know about and see CONFIG_* variables are kernel hackers, not the normal kconfig users.

Quoted 4 lines

Also, when working on a specific feature of the kernel, I tend to install both a kernel with the CONFIG_ option set and one with the option unset. Scripts to do that can twiddle the .config file, but it would be more convenient if kbuild could avoid that.

I'm wondering why you don't use two different O= output directories instead?

Depending on the CONFIG_ option in question this might even greatly reduce your compile times.

Quoted 5 lines

I'm wondering why you don't use two different O= output directories instead?

Depending on the CONFIG_ option in question this might even greatly reduce your compile times.

/me is filled with wonder at the discovery that .config is saved in the O= directory. Thanks a lot Adrian for this time saver. So it's not strictly an output directory, more a build directory.

Quoted 2 lines

So it's not strictly an
output directory, more a build directory.

The opposite....
All output is placed there - including the configuration generated by the *config frontends.

The variable K64BIT can now be used to select the
value of CONFIG_64BIT.

This is for example useful for powerpc to generate allmodconfig for both bit sizes - like this:
make ARCH=powerpc K64BIT=y
make ARCH=powerpc K64BIT=n

To use this the Kconfig file must use "64BIT" as the config value to select between 32 and 64 bit.

Signed-off-by Sam Ravnborg <[email protected]>

---
 scripts/kconfig/conf.c      |    1 +
 scripts/kconfig/confdata.c  |   27 +++++++++++++++++++++++++++
 scripts/kconfig/lkc_proto.h |    1 +
 3 files changed, 29 insertions(+), 0 deletions(-)

scripts/kconfig/conf.c +1 -0

index a38787a..c6bee85 100644
@@ -591,6 +591,7 @@ int main(int ac, char **av)
 			conf_read_simple(name, S_DEF_USER);
 		else if (!stat("all.config", &tmpstat))
 			conf_read_simple("all.config", S_DEF_USER);
+		conf_set_env_sym("K64BIT", "64BIT", S_DEF_USER);
 		break;
 	default:
 		break;

scripts/kconfig/confdata.c +0 -0

index e0f402f..0cb7555 100644

scripts/kconfig/confdata.c +8 -0

+		def_flags = SYMBOL_DEF << def;
+		if (def == S_DEF_USER) {
+			sym = sym_find(symname);
+			if (!sym)
+				return 1;
+		} else {
+			sym = sym_lookup(symname, 0);
+			if (sym->type == S_UNKNOWN)

Quoted 35 lines · On Sat, 10 Nov 2007 21:43:26 +0100 Sam Ravnborg wrote:

The variable K64BIT can now be used to select the
value of CONFIG_64BIT.

This is for example useful for powerpc to generate allmodconfig for both bit sizes - like this:
make ARCH=powerpc K64BIT=y
make ARCH=powerpc K64BIT=n

To use this the Kconfig file must use "64BIT" as the config value to select between 32 and 64 bit.

Signed-off-by Sam Ravnborg <[email protected]>

---
 scripts/kconfig/conf.c      |    1 +
 scripts/kconfig/confdata.c  |   27 +++++++++++++++++++++++++++
 scripts/kconfig/lkc_proto.h |    1 +
 3 files changed, 29 insertions(+), 0 deletions(-)

scripts/kconfig/conf.c +1 -0

index a38787a..c6bee85 100644
@@ -591,6 +591,7 @@ int main(int ac, char **av)
 			conf_read_simple(name, S_DEF_USER);
 		else if (!stat("all.config", &tmpstat))
 			conf_read_simple("all.config", S_DEF_USER);
+		conf_set_env_sym("K64BIT", "64BIT", S_DEF_USER);
 		break;
 	default:
 		break;

scripts/kconfig/confdata.c +0 -0

index e0f402f..0cb7555 100644

scripts/kconfig/confdata.c static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p) · line 148

Quoted 4 lines

scripts/kconfig/confdata.c +1 -0

@@ -145,6 +145,33 @@ static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p)
 	return 0;
 }
 
+/* Read an environment variable and assign the vaule to the symbol */

value

scripts/kconfig/confdata.c static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p) · line 159

Quoted 11 lines

scripts/kconfig/confdata.c +11 -0

+int conf_set_env_sym(const char *env, const char *symname, int def)
+{
+	struct symbol *sym;
+	char *p;
+	int def_flags;
+
+	p = getenv(env);
+	if (p) {
+		char warning[100];
+		sprintf(warning, "Environment variable (%s = \"%s\")", env, p);
+		conf_filename = warning;

What's with <warning> and <conf_filename> here? I don't see how they are used in this function or in the caller of this function.

scripts/kconfig/confdata.c +7 -0

+	if (p) {
+		char warning[100];
+		sprintf(warning, "Environment variable (%s = \"%s\")", env, p);
+		conf_filename = warning;
+		def_flags = SYMBOL_DEF << def;
+		if (def == S_DEF_USER) {
+			sym = sym_find(symname);

Hi,

Quoted 7 lines · Sam Ravnborg

scripts/kconfig/confdata.c +7 -0

+	if (p) {
+		char warning[100];
+		sprintf(warning, "Environment variable (%s = \"%s\")", env, p);
+		conf_filename = warning;
+		def_flags = SYMBOL_DEF << def;
+		if (def == S_DEF_USER) {
+			sym = sym_find(symname);

scripts/kconfig/confdata.c static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p) · line 172

Quoted 10 lines

scripts/kconfig/confdata.c +10 -0

+			if (!sym)
+				return 1;
+		} else {
+			sym = sym_lookup(symname, 0);
+			if (sym->type == S_UNKNOWN)
+				sym->type = S_OTHER;
+		}
+		conf_set_sym_val(sym, def, def_flags, p);
+	}
+	return 0;

This is more complex than necessary, this should be enough:

	sym = sym_find(symname);
	if (sym)
		sym_set_string_value(sym, p);

This is not a direct user interface, so the potential stricter error checking is not really needed.

In general I think it's problematic that this is only checked, when the config system is called, i.e. with a configured kernel adding ARCH would have no effect, what makes this more confusing is that one can later omit the ARCH variable, since it's saved in the .config.

The value can be supplied on the command-line so we need to validate input.

The code is a copy of what happen when reading a all.config file and the functionality should be equal.
Can we make that part simpler too?

By the way - I have never understood the purpose of the flags (S_DEF_USER etc.) Can we have a few comments added to their definition?

One of the blockers are that kconfig does not support more than one prompt for a choice symbol. Is this something you can fix - or sketch how to fix it?

Hi,

Quoted 1 line · Sam Ravnborg

The value can be supplied on the command-line so we need to validate input.

Is there a need for this?

BTW ARCH was already available as a value in the Kconfig files, so setting the 64BIT option was already possible without any changes the kconfig system, e.g.:

config 64BIT

	bool "64 Bit kernel" if ARCH!="i386" && ARCH!="x86_64"
	default ARCH="x86_64"

The patch below adds some features to it:
- it allows to import any environment variable by specifying "option env=..."
- it generates a dependency on it, so the kernel config is updated if it changes.

Please revert the K64BIT changes and use this instead.

Quoted 4 lines

The code is a copy of what happen when reading a all.config file and the functionality should be equal.
Can we make that part simpler too?

These are two different uses, when reading a .config only the basic syntax is checked, but not the value itself.

Quoted 2 lines

By the way - I have never understood the purpose of the flags (S_DEF_USER etc.) Can we have a few comments added to their definition?

It allows to hold multiple configs, a user of it is conf_split_config() which loads another config and compares to the current config and updates the files under include/config as needed.
It could also be used by front ends to display what actually changed compared to e.g. the saved config.

Quoted 2 lines

One of the blockers are that kconfig does not support more than one prompt for a choice symbol. Is this something you can fix - or sketch how to fix it?

The basic idea is to add a name to the choice, so multiple choices can be grouped together. This requires some changes to the dependency check to make sure one choice option doesn't depend on another (which is currently enforced by the syntax).

Quoted 3 lines

Quoted 1 line

The value can be supplied on the command-line so we need to validate input.

Is there a need for this?

Yes. We would like to set 64BIT or not in other than x86 cases. And way forward was not to override ARCH as in the x86 case.

Quoted 1 line

Please revert the K64BIT changes and use this instead.

I will finish up your patch and target it for next merge window.

Quoted 2 lines

These are two different uses, when reading a .config only the basic syntax is checked, but not the value itself.

This is wrong considering the amount of people that hand edit the .config file.

Quoted 5 lines

Quoted 3 lines

Quoted 1 line

The value can be supplied on the command-line so we need to validate input.

Is there a need for this?

Yes. We would like to set 64BIT or not in other than x86 cases. And way forward was not to override ARCH as in the x86 case.

Can we please can get some consistency in this?
We have a .config file for a reason, what's wrong with using it?

Quoted 4 lines

Quoted 2 lines

Please revert the K64BIT changes and use this instead.

I will finish up your patch and target it for next merge window.

Why can't this be fixed properly now? You don't even need this patch, just use ARCH to set 64BIT in the Kconfig as I've shown.

Quoted 4 lines

Quoted 3 lines

These are two different uses, when reading a .config only the basic syntax is checked, but not the value itself.

This is wrong considering the amount of people that hand edit the .config file.

It's not, the actual symbol value is set later depending on the dependency constraints.

Quoted 2 lines

Can we please can get some consistency in this?
We have a .config file for a reason, what's wrong with using it?

We need to set a selected few values in a few cases where we do not have a .config file.
allmodconfig for x86 for instance. We would like to generate a 32-bit and a 64-bit version.

Quoted 4 lines

Quoted 3 lines

Quoted 1 line

Please revert the K64BIT changes and use this instead.

I will finish up your patch and target it for next merge window.

Quoted 2 lines

Why can't this be fixed properly now? You don't even need this patch, just use ARCH to set 64BIT in the Kconfig as I've shown.

Because the patch is in mainline and has been tested by a lot of people during the last week. And as the functionality is almost equal I do not see it as a big deal to have the less-perfect solution in one kernel release.

And the only reason the patch were applied to mainline was to fix the build of the merged x86 architecute - otherwise it was in no way -rc material.

Quoted 6 lines

Quoted 3 lines

Quoted 2 lines

These are two different uses, when reading a .config only the basic syntax is checked, but not the value itself.

This is wrong considering the amount of people that hand edit the .config file.

It's not, the actual symbol value is set later depending on the dependency constraints.

My point is that the .config file is handedited so the syntax should be checked to best possible extent. If someone specify CONFIG_64BIT=64 we should error out.

Hi,

Quoted 7 lines · Sam Ravnborg

Quoted 2 lines

Can we please can get some consistency in this?
We have a .config file for a reason, what's wrong with using it?

We need to set a selected few values in a few cases where we do not have a .config file.
allmodconfig for x86 for instance. We would like to generate a 32-bit and a 64-bit version.

This can already be set via all.config/allmod.config.
Where is this need coming from? The point is that I don't like to add an interface, which is maybe used by two people, who should be perfectly capable using an existing superior mechanism.

Quoted 11 lines

Quoted 7 lines

Quoted 4 lines

Quoted 2 lines

Please revert the K64BIT changes and use this instead.

I will finish up your patch and target it for next merge window.

Why can't this be fixed properly now? You don't even need this patch, just use ARCH to set 64BIT in the Kconfig as I've shown.

Because the patch is in mainline and has been tested by a lot of people during the last week. And as the functionality is almost equal I do not see it as a big deal to have the less-perfect solution in one kernel release.

Quoted 2 lines

And the only reason the patch were applied to mainline was to fix the build of the merged x86 architecute - otherwise it was in no way -rc material.

I showed you a solution, which requires no patch at all, while your patch adds extra functionality which is questionable.
Why is a quick hack preferable over a proper solution?
Either explain why my solution isn't usable or _please_ revert the K64BIT changes.

You suggest just to check ARCH value and not apply your patch. This was not my initial understanding as was hopefully obvious from my reply.

If user did NOT specify ARCH we should use the kernel configuration - which your solution fail to do.

Hi,

Quoted 2 lines · Sam Ravnborg

You suggest just to check ARCH value and not apply your patch. This was not my initial understanding as was hopefully obvious from my reply.

This patch only adds some extra features.

Quoted 2 lines

If user did NOT specify ARCH we should use the kernel configuration - which your solution fail to do.

To make this easy I attached the patch which reverts the problematic changes and then you only need this simple change to force the 64BIT value for ARCH={i386,x86_64}, otherwise it's set by the user:

bye, Roman

Signed-off-by Roman Zippel <[email protected]>

---
 Makefile         |    3 ++-
 arch/x86/Kconfig |    4 ++--
 2 files changed, 4 insertions(+), 3 deletions(-)

Index: linux-2.6/Makefile
===================================================================

Makefile +2 -1

@@ -165,7 +165,8 @@ export srctree objtree VPATH TOPDIR
 # then ARCH is assigned, getting whatever value it gets normally, and 
 # SUBARCH is subsequently ignored.
 
-SUBARCH := $(shell uname -m | sed -e s/i.86/i386/ -e s/sun4u/sparc64/ \
+SUBARCH := $(shell uname -m | sed -e s/i.86/x86/ -e s/x86_64/x86/ \
+				  -e s/sun4u/sparc64/ \
 				  -e s/arm.*/arm/ -e s/sa110/arm/ \
 				  -e s/s390x/s390/ -e s/parisc64/parisc/ \
 				  -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \

Index: linux-2.6/arch/x86/Kconfig
===================================================================

This all began (AFAIK) because some of us want to continue to be able to specify ARCH={i386,x86_64} on the (make) command line -- not by using a .config file. Taking away ARCH= on the command line is a regression (in some minds, at least), so Sam provided that capability. Is that capability still present after this patch?

Quoted 2 lines

If user did NOT specify ARCH we should use the kernel configuration - which your solution fail to do.

To make this easy I attached the patch which reverts the problematic changes and then you only need this simple change to force the 64BIT value for ARCH={i386,x86_64}, otherwise it's set by the user:

1) make all*config, randconfig, defconfig is broken on 64-bit boxes

2) A pure code refactoring patch is reverted for no obvious reason

3) Behavioral changes are not documented:
- 32-bit/64-bit can only be selected in config is you specify ARCH=x86

- ARCH= takes precedence over kernel config for a configured kernel

4) The changelogs miss title on reverted patches

The patch below adds some features to it:
- it allows to import any environment variable by specifying "option env=..."
- it generates a dependency on it, so the kernel config is updated if it changes.

Signed-off-by Roman Zippel <[email protected]>

---
 init/Kconfig                         |    4 ++
 scripts/kconfig/expr.c               |   16 +++++-----
 scripts/kconfig/expr.h               |    5 +--
 scripts/kconfig/lkc.h                |    5 +++
 scripts/kconfig/menu.c               |    7 +++-
 scripts/kconfig/qconf.cc             |   15 ++-------
 scripts/kconfig/symbol.c             |   53 +++++++++++++++++++++++++++++------
 scripts/kconfig/util.c               |   25 +++++++++++++++-
 scripts/kconfig/zconf.gperf          |    1 
 scripts/kconfig/zconf.hash.c_shipped |   45 ++++++++++++++++-------------
 10 files changed, 123 insertions(+), 53 deletions(-)

Index: linux-2.6/init/Kconfig
===================================================================

init/Kconfig +4 -0

@@ -7,6 +7,10 @@ config DEFCONFIG_LIST
 	default "/boot/config-$UNAME_RELEASE"
 	default "arch/$ARCH/defconfig"
 
+config ARCH
+	string
+	option env="ARCH"
+
 menu "General setup"
 
 config EXPERIMENTAL

Index: linux-2.6/scripts/kconfig/expr.c
===================================================================

scripts/kconfig/expr.c +8 -8

@@ -87,7 +87,7 @@ struct expr *expr_copy(struct expr *org)
 		break;
 	case E_AND:
 	case E_OR:
-	case E_CHOICE:
+	case E_LIST:
 		e->left.expr = expr_copy(org->left.expr);
 		e->right.expr = expr_copy(org->right.expr);
 		break;

@@ -217,7 +217,7 @@ int expr_eq(struct expr *e1, struct expr
 		expr_free(e2);
 		trans_count = old_count;
 		return res;
-	case E_CHOICE:
+	case E_LIST:
 	case E_RANGE:
 	case E_NONE:
 		/* panic */;

@@ -648,7 +648,7 @@ struct expr *expr_transform(struct expr 
 	case E_EQUAL:
 	case E_UNEQUAL:
 	case E_SYMBOL:
-	case E_CHOICE:
+	case E_LIST:
 		break;
 	default:
 		e->left.expr = expr_transform(e->left.expr);

@@ -932,7 +932,7 @@ struct expr *expr_trans_compare(struct e
 		break;
 	case E_SYMBOL:
 		return expr_alloc_comp(type, e->left.sym, sym);
-	case E_CHOICE:
+	case E_LIST:
 	case E_RANGE:
 	case E_NONE:
 		/* panic */;

@@ -1000,9 +1000,9 @@ int expr_compare_type(enum expr_type t1,
 		if (t2 == E_OR)
 			return 1;
 	case E_OR:
-		if (t2 == E_CHOICE)
+		if (t2 == E_LIST)
 			return 1;
-	case E_CHOICE:
+	case E_LIST:
 		if (t2 == 0)
 			return 1;
 	default:

@@ -1053,11 +1053,11 @@ void expr_print(struct expr *e, void (*f
 		fn(data, NULL, " && ");
 		expr_print(e->right.expr, fn, data, E_AND);
 		break;
-	case E_CHOICE:
+	case E_LIST:
 		fn(data, e->right.sym, e->right.sym->name);
 		if (e->left.expr) {
 			fn(data, NULL, " ^ ");
-			expr_print(e->left.expr, fn, data, E_CHOICE);
+			expr_print(e->left.expr, fn, data, E_LIST);
 		}
 		break;
 	case E_RANGE:

Index: linux-2.6/scripts/kconfig/expr.h
===================================================================

scripts/kconfig/expr.h +3 -2

@@ -32,7 +32,7 @@ typedef enum tristate {
 } tristate;
 
 enum expr_type {
-	E_NONE, E_OR, E_AND, E_NOT, E_EQUAL, E_UNEQUAL, E_CHOICE, E_SYMBOL, E_RANGE
+	E_NONE, E_OR, E_AND, E_NOT, E_EQUAL, E_UNEQUAL, E_LIST, E_SYMBOL, E_RANGE
 };
 
 union expr_data {

@@ -105,7 +105,8 @@ struct symbol {
 #define SYMBOL_HASHMASK		0xff
 
 enum prop_type {
-	P_UNKNOWN, P_PROMPT, P_COMMENT, P_MENU, P_DEFAULT, P_CHOICE, P_SELECT, P_RANGE
+	P_UNKNOWN, P_PROMPT, P_COMMENT, P_MENU, P_DEFAULT, P_CHOICE,
+	P_SELECT, P_RANGE, P_ENV
 };
 
 struct property {

Index: linux-2.6/scripts/kconfig/lkc.h
===================================================================

scripts/kconfig/lkc.h +2 -0

@@ -44,6 +44,7 @@ extern "C" {
 
 #define T_OPT_MODULES		1
 #define T_OPT_DEFCONFIG_LIST	2
+#define T_OPT_ENV		3
 
 struct kconf_id {
 	int name;

@@ -74,6 +75,7 @@ void kconfig_load(void);
 
 /* menu.c */
 void menu_init(void);
+void menu_warn(struct menu *menu, const char *fmt, ...);
 struct menu *menu_add_menu(void);
 void menu_end_menu(void);
 void menu_add_entry(struct symbol *sym);

scripts/kconfig/lkc.h +3 -0

+extern struct expr *sym_env_list;
+
 void sym_init(void);
 void sym_clear_all_valid(void);
 void sym_set_all_changed(void);

@@ -110,6 +114,7 @@ void sym_set_changed(struct symbol *sym)
 struct symbol *sym_check_deps(struct symbol *sym);
 struct property *prop_alloc(enum prop_type type, struct symbol *sym);
 struct symbol *prop_get_symbol(struct property *prop);
+struct property *sym_get_env_prop(struct symbol *sym);
 
 static inline tristate sym_get_tristate_value(struct symbol *sym)
 {

Index: linux-2.6/scripts/kconfig/menu.c
===================================================================

scripts/kconfig/menu.c +5 -2

@@ -15,7 +15,7 @@ static struct menu **last_entry_ptr;
 struct file *file_list;
 struct file *current_file;
 
-static void menu_warn(struct menu *menu, const char *fmt, ...)
+void menu_warn(struct menu *menu, const char *fmt, ...)
 {
 	va_list ap;
 	va_start(ap, fmt);

@@ -172,6 +172,9 @@ void menu_add_option(int token, char *ar
 		else if (sym_defconfig_list != current_entry->sym)
 			zconf_error("trying to redefine defconfig symbol");
 		break;
+	case T_OPT_ENV:
+		prop_add_env(arg);
+		break;
 	}
 }
 

@@ -331,7 +334,7 @@ void menu_finalize(struct menu *parent)
 			prop = sym_get_choice_prop(sym);
 			for (ep = &prop->expr; *ep; ep = &(*ep)->left.expr)
 				;
-			*ep = expr_alloc_one(E_CHOICE, NULL);
+			*ep = expr_alloc_one(E_LIST, NULL);
 			(*ep)->right.sym = menu->sym;
 		}
 		if (menu->list && (!menu->prompt || !menu->prompt->text)) {

Index: linux-2.6/scripts/kconfig/qconf.cc
===================================================================

scripts/kconfig/qconf.cc +4 -1

@@ -1083,7 +1083,10 @@ QString ConfigInfoView::debug_info(struc
 			debug += "</a><br>";
 			break;
 		case P_DEFAULT:
-			debug += "default: ";
+		case P_SELECT:
+		case P_ENV:
+			debug += prop_get_type_name(prop->type);
+			debug += ": ";
 			expr_print(prop->expr, expr_print_help, &debug, E_NONE);
 			debug += "<br>";
 			break;

scripts/kconfig/qconf.cc +0 -0

 		default:
 			debug += "unknown property: ";
 			debug += prop_get_type_name(prop->type);

Index: linux-2.6/scripts/kconfig/symbol.c
===================================================================

scripts/kconfig/symbol.c +11 -7

@@ -34,6 +34,8 @@ struct symbol *sym_defconfig_list;
 struct symbol *modules_sym;
 tristate modules_val;
 
+struct expr *sym_env_list;
+
 void sym_add_default(struct symbol *sym, const char *def)
 {
 	struct property *prop = prop_alloc(P_DEFAULT, sym);

@@ -54,13 +56,6 @@ void sym_init(void)
 
 	uname(&uts);
 
-	sym = sym_lookup("ARCH", 0);
-	sym->type = S_STRING;
-	sym->flags |= SYMBOL_AUTO;
-	p = getenv("ARCH");
-	if (p)
-		sym_add_default(sym, p);
-
 	sym = sym_lookup("KERNELVERSION", 0);
 	sym->type = S_STRING;
 	sym->flags |= SYMBOL_AUTO;

@@ -117,6 +112,15 @@ struct property *sym_get_choice_prop(str
 	return NULL;
 }
 
+struct property *sym_get_env_prop(struct symbol *sym)
+{
+	struct property *prop;
+
+	for_all_properties(sym, prop, P_ENV)
+		return prop;
+	return NULL;
+}
+
 struct property *sym_get_default_prop(struct symbol *sym)
 {
 	struct property *prop;

scripts/kconfig/symbol.c +6 -1

 	sym->curr = newval;
 	if (sym_is_choice(sym) && newval.tri == yes)
 		sym->curr.val = sym_calc_choice(sym);

@@ -849,7 +856,7 @@ struct property *prop_alloc(enum prop_ty
 struct symbol *prop_get_symbol(struct property *prop)
 {
 	if (prop->expr && (prop->expr->type == E_SYMBOL ||
-			   prop->expr->type == E_CHOICE))
+			   prop->expr->type == E_LIST))
 		return prop->expr->left.sym;
 	return NULL;
 }

@@ -859,6 +866,8 @@ const char *prop_get_type_name(enum prop
 	switch (type) {
 	case P_PROMPT:
 		return "prompt";
+	case P_ENV:
+		return "env";
 	case P_COMMENT:
 		return "comment";
 	case P_MENU:

@@ -876,3 +885,31 @@ const char *prop_get_type_name(enum prop
 	}
 	return "unknown";
 }
+
+void prop_add_env(const char *env)
+{

scripts/kconfig/symbol.c +4 -0

+		return;
+	}
+
+	prop = prop_alloc(P_ENV, sym);

scripts/kconfig/symbol.c +1 -0

+}

Index: linux-2.6/scripts/kconfig/util.c
===================================================================

scripts/kconfig/util.c +23 -2

@@ -29,6 +29,7 @@ struct file *file_lookup(const char *nam
 /* write a dependency file as used by kbuild to track dependencies */
 int file_write_dep(const char *name)
 {
+	struct expr *e;
 	struct file *file;
 	FILE *out;
 

@@ -45,8 +46,28 @@ int file_write_dep(const char *name)
 			fprintf(out, "\t%s\n", file->name);
 	}
 	fprintf(out, "\ninclude/config/auto.conf: \\\n"
-		     "\t$(deps_config)\n\n"
-		     "$(deps_config): ;\n");
+		     "\t$(deps_config)\n\n");
+
+	for (e = sym_env_list; e; e = e->left.expr) {
+		struct property *p;
+		struct symbol *sym, *env_sym;
+		const char *value;
+
+		sym = e->right.sym;
+		p = sym_get_env_prop(sym);
+		env_sym = prop_get_symbol(p);
+		if (!env_sym)
+			continue;
+		value = sym_get_string_value(sym);
+		if ((sym->type == S_BOOLEAN || sym->type == S_TRISTATE) &&
+		    sym_get_tristate_value(sym) == no)
+			value = "";
+		fprintf(out, "ifneq \"$(%s)\" \"%s\"\n", env_sym->name, value);
+		fprintf(out, "include/config/auto.conf: FORCE\n");
+		fprintf(out, "endif\n");
+	}
+
+	fprintf(out, "\n$(deps_config): ;\n");
 	fclose(out);
 	rename("..config.tmp", name);
 	return 0;

Index: linux-2.6/scripts/kconfig/zconf.gperf
===================================================================

scripts/kconfig/zconf.gperf +1 -0

@@ -41,4 +41,5 @@ option,		T_OPTION,	TF_COMMAND
 on,		T_ON,		TF_PARAM
 modules,	T_OPT_MODULES,	TF_OPTION
 defconfig_list,	T_OPT_DEFCONFIG_LIST,TF_OPTION
+env,		T_OPT_ENV,	TF_OPTION
 %%

Please get back to me so we can finsih this patch and have it applied. I will split the patch in two btw.

scripts/kconfig/symbol.c void sym_calc_value(struct symbol *sym) · line 356

Quoted 3 lines

scripts/kconfig/symbol.c +3 -0

+	if (sym->flags & SYMBOL_AUTO)
+		sym->flags &= ~SYMBOL_WRITE;
+

Why is this change needed?
It is non-obvious to me so please explain and I will add a comment.

I did it like this:

			menu_warn(current_entry,
			          "config %s: redefining environment symbol from '%s' to '%s'",
			          sym->name, env, sym2->name);

Hi,

Quoted 2 lines · Sam Ravnborg

Please get back to me so we can finsih this patch and have it applied. I will split the patch in two btw.

I reworked the patch a little and split it into three.

Quoted 7 lines

scripts/kconfig/symbol.c void sym_calc_value(struct symbol *sym) · line 356

Quoted 4 lines

scripts/kconfig/symbol.c +3 -0

+	if (sym->flags & SYMBOL_AUTO)
+		sym->flags &= ~SYMBOL_WRITE;
+

Why is this change needed?
It is non-obvious to me so please explain and I will add a comment.

Automatically generated symbols are not saved, this was previously not needed as they weren't in the menu structure.

Quoted 5 lines

I did it like this:

			menu_warn(current_entry,
			          "config %s: redefining environment symbol from '%s' to '%s'",
			          sym->name, env, sym2->name);

I omitted the prefix, it's inconsistent with other warnings.

As discussed in another thread the right thing is to add a generic solution to select between 32 and 64 bit - useable for powerpc, s390, ppc et al.

First step was to teach kconfig how to force 64BIT to a specific value. The x86 Kconfig file needed a small twist to use 64BIT as the symbol to seelct 32 or 64 bit.
Then it was simple to add backward compatibility ARCH= settings.

The patchset is not yet pushed out - I will await a bit feedback first.

Shortlog and diffstat.
kconfig: factor out code in confdata.c
kconfig: use $K64BIT to set 64BIT with all*config targets
x86: Use CONFIG_64BIT to select between 32 and 64 bit in Kconfig
kconfig: document make K64BIT=y in README
x86: introduce ARCH=i386,ARCH=x86_64 to select 32/64 bit

Quoted 8 lines · On Sat, 10 Nov 2007 21:40:38 +0100 Sam Ravnborg wrote:

As discussed in another thread the right thing is to add a generic solution to select between 32 and 64 bit - useable for powerpc, s390, ppc et al.

First step was to teach kconfig how to force 64BIT to a specific value. The x86 Kconfig file needed a small twist to use 64BIT as the symbol to seelct 32 or 64 bit.
Then it was simple to add backward compatibility ARCH= settings.

Quoted 8 lines

The patchset is not yet pushed out - I will await a bit feedback first.

Shortlog and diffstat.
kconfig: factor out code in confdata.c
kconfig: use $K64BIT to set 64BIT with all*config targets
x86: Use CONFIG_64BIT to select between 32 and 64 bit in Kconfig
kconfig: document make K64BIT=y in README
x86: introduce ARCH=i386,ARCH=x86_64 to select 32/64 bit

Hi Sam,
Looks good to me and should satisfy our habits^w usages models.

The one minor question is the environment variable name (K64BIT or something else, like Guillaume brought up). Personally I don't care how it's spelled. IOW, K64BIT is sufficient, but if there is a goal to be able to place any CONFIG_symbol on the command line or as an env. variable, they might as well all be named with CONFIG_*.

As discussed in another thread the right thing is to add a generic solution to select between 32 and 64 bit - useable for powerpc, s390, ppc et al.
...

Sam

Quoted 3 lines · Sam Ravnborg

As discussed in another thread the right thing is to add a generic solution to select between 32 and 64 bit - useable for powerpc, s390, ppc et al.
...

I seriously question this would be "the right thing".

32/64bit isn't that special that this and only this option would require special casing, and the KISS principle of having only one way to specify something like this has it's advantages.

As discussed in another thread the right thing is to add a generic solution to select between 32 and 64 bit - useable for powerpc, s390, ppc et al.

Hi,

Quoted 2 lines · Sam Ravnborg

As discussed in another thread the right thing is to add a generic solution to select between 32 and 64 bit - useable for powerpc, s390, ppc et al.

Could you please point me to this discussion?