Re: [linuxsh-dev] Back from the dead

[NIIBE Y. <gn...@ch...>]

NIIBE Yutaka wrote:
 > Besides, I think that it is better to use some linker magic for
 > `all_vecs' handling.  Currently, when people want to add another
 > system, he has to touch setup.c for the inclusion.  I think that we
 > can add our own ELF section for the machine vector, then all that he
 > need is adding the specific file and modify Makefile.  No need to
 > touch other files.  Sounds good?

Like this one.  Any comments are appreciated.  If it's OK, I will add
ChangeLog entries and commit this over the changes by Stuart.

Index: arch/sh/vmlinux.lds.S
===================================================================
RCS file: /cvsroot/linuxsh/kernel/arch/sh/vmlinux.lds.S,v
retrieving revision 1.5
diff -u -r1.5 vmlinux.lds.S
--- arch/sh/vmlinux.lds.S	2000/07/20 06:50:06	1.5
+++ arch/sh/vmlinux.lds.S	2000/08/03 08:11:21
@@ -61,6 +61,9 @@
   __initcall_start = .;
   .initcall.init : { *(.initcall.init) }
   __initcall_end = .;
+  __machvec_start = .;
+  .machvec.init : { *(.machvec.init) }
+  __machvec_end = .;
   . = ALIGN(4096);
   __init_end = .;
 
Index: include/asm-sh/machvec_init.h
===================================================================
RCS file: /cvsroot/linuxsh/kernel/include/asm-sh/machvec_init.h,v
retrieving revision 1.1
diff -u -r1.1 machvec_init.h
--- include/asm-sh/machvec_init.h	2000/07/31 12:31:12	1.1
+++ include/asm-sh/machvec_init.h	2000/08/03 08:11:30
@@ -26,11 +26,15 @@
  * alias this one vector to alpha_mv, so no copy is needed.
  *
  * Upshot: set __initdata to nothing for non-GENERIC kernels.
+ *
+ * Note we do the same thing for the UNKNOWN kernel, as we need to write
+ * to the machine vector while setting it up.
  */
 
-#ifdef CONFIG_SH_GENERIC
+#if defined(CONFIG_SH_GENERIC) || defined(CONFIG_SH_UNKNOWN)
 #define __initmv __initdata
 #define ALIAS_MV(x)
+#define REGISTER_MV(x) long pointer_to_##x __attribute__((unused,__section__ (".machvec.init"))) = (long)&mv_##x;
 #else
 #define __initmv
 
@@ -44,6 +48,7 @@
 #define ALIAS_MV(system) \
   asm(".global sh_mv\nsh_mv = mv_"#system );
 #endif
+#define REGISTER_MV(x)
 #endif /* GENERIC */
 
 #endif /* __SH_MACHVEC_INIT_H */
Index: arch/sh/kernel/mach_hp600.c
===================================================================
RCS file: /cvsroot/linuxsh/kernel/arch/sh/kernel/mach_hp600.c,v
retrieving revision 1.3
diff -u -r1.3 mach_hp600.c
--- arch/sh/kernel/mach_hp600.c	2000/08/01 03:18:38	1.3
+++ arch/sh/kernel/mach_hp600.c	2000/08/03 08:11:21
@@ -61,3 +61,4 @@
 	mv_hw_hd64461:		1,
 };
 ALIAS_MV(hp600)
+REGISTER_MV(hp600)
Index: arch/sh/kernel/mach_se.c
===================================================================
RCS file: /cvsroot/linuxsh/kernel/arch/sh/kernel/mach_se.c,v
retrieving revision 1.1
diff -u -r1.1 mach_se.c
--- arch/sh/kernel/mach_se.c	2000/07/31 12:30:17	1.1
+++ arch/sh/kernel/mach_se.c	2000/08/03 08:11:21
@@ -78,3 +78,4 @@
 	mv_hw_se:		1,
 };
 ALIAS_MV(se)
+REGISTER_MV(se)
Index: arch/sh/kernel/mach_unknown.c
===================================================================
RCS file: /cvsroot/linuxsh/kernel/arch/sh/kernel/mach_unknown.c,v
retrieving revision 1.1
diff -u -r1.1 mach_unknown.c
--- arch/sh/kernel/mach_unknown.c	2000/07/31 12:30:36	1.1
+++ arch/sh/kernel/mach_unknown.c	2000/08/03 08:11:21
@@ -66,3 +66,4 @@
 	mv_isa_port2addr:	unknown_isa_port2addr,
 };
 ALIAS_MV(unknown)
+REGISTER_MV(unknown)
Index: arch/sh/kernel/setup.c
===================================================================
RCS file: /cvsroot/linuxsh/kernel/arch/sh/kernel/setup.c,v
retrieving revision 1.10
diff -u -r1.10 setup.c
--- arch/sh/kernel/setup.c	2000/08/01 03:18:38	1.10
+++ arch/sh/kernel/setup.c	2000/08/03 08:11:21
@@ -63,16 +64,6 @@
 extern int root_mountflags;
 extern int _text, _etext, _edata, _end;
 
-/* __attribute__(weak) doesn't appear to do anything */
-#define WEAK(X) \
-	extern struct sh_machine_vector X; \
-	asm(".weak "#X)
-
-WEAK(mv_unknown);
-WEAK(mv_hp600);
-WEAK(mv_od);
-WEAK(mv_se);
-
 #define MV_NAME_SIZE 32
 
 static struct sh_machine_vector* __init get_mv_byname(const char* name);
@@ -426,14 +471,11 @@
 struct sh_machine_vector* __init get_mv_byname(const char* name)
 {
 	extern int strcasecmp(const char *, const char *);
-	static struct sh_machine_vector *all_vecs[] __initlocaldata =
-	{
-		&mv_hp600,
-		&mv_od,
-		&mv_se,
-	};
+	extern long __machvec_start, __machvec_end;
+	struct sh_machine_vector **all_vecs =
+		(struct sh_machine_vector **)&__machvec_start;
 
-	int i, n = sizeof(all_vecs)/sizeof(*all_vecs);
+	int i, n = (&__machvec_end - &__machvec_start);
 
 	for (i = 0; i < n; ++i) {
 		struct sh_machine_vector *mv = all_vecs[i];
Index: arch/sh/overdrive/mach.c
===================================================================
RCS file: /cvsroot/linuxsh/kernel/arch/sh/overdrive/mach.c,v
retrieving revision 1.1
diff -u -r1.1 mach.c
--- arch/sh/overdrive/mach.c	2000/07/31 12:38:20	1.1
+++ arch/sh/overdrive/mach.c	2000/08/03 08:11:21
@@ -71,3 +71,4 @@
 };
 
 ALIAS_MV(od)
+REGISTER_MV(od)