x86: cleanup machine_specific_memory_setup, v2

1. let 64bit support 88 and e801 too
2. introduce default_machine_specific_memory_setup, and reuse it
   for voyager

v2: fix 64 bit compiling
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/kernel/e820.c

@@ -1029,7 +1029,7 @@ void __init e820_reserve_resources(void)
 	}
 }
 
-char *__init __attribute__((weak)) machine_specific_memory_setup(void)
+char *__init default_machine_specific_memory_setup(void)
 {
 	char *who = "BIOS-e820";
 	int new_nr;
@@ -1045,10 +1045,7 @@ char *__init __attribute__((weak)) machine_specific_memory_setup(void)
 			&new_nr);
 	boot_params.e820_entries = new_nr;
 	if (copy_e820_map(boot_params.e820_map, boot_params.e820_entries) < 0) {
-#ifdef CONFIG_X86_64
-		early_panic("Cannot find a valid memory map");
-#else
-		unsigned long mem_size;
+		u64 mem_size;
 
 		/* compare results from other methods and take the greater */
 		if (boot_params.alt_mem_k
@@ -1063,13 +1060,17 @@ char *__init __attribute__((weak)) machine_specific_memory_setup(void)
 		e820.nr_map = 0;
 		e820_add_region(0, LOWMEMSIZE(), E820_RAM);
 		e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
-#endif
 	}
 
 	/* In case someone cares... */
 	return who;
 }
 
+char *__init __attribute__((weak)) machine_specific_memory_setup(void)
+{
+	return default_machine_specific_memory_setup();
+}
+
 /* Overridden in paravirt.c if CONFIG_PARAVIRT */
 char * __init __attribute__((weak)) memory_setup(void)
 {

arch/x86/mach-voyager/setup.c

@@ -104,35 +104,5 @@ char *__init machine_specific_memory_setup(void)
 		return who;
 	}
 
-	who = "BIOS-e820";
-
-	/*
-	 * Try to copy the BIOS-supplied E820-map.
-	 *
-	 * Otherwise fake a memory map; one section from 0k->640k,
-	 * the next section from 1mb->appropriate_mem_k
-	 */
-	new_nr = boot_params.e820_entries;
-	sanitize_e820_map(boot_params.e820_map,
-			ARRAY_SIZE(boot_params.e820_map),
-			&new_nr);
-	boot_params.e820_entries = new_nr;
-	if (copy_e820_map(boot_params.e820_map, boot_params.e820_entries)
-	    < 0) {
-		unsigned long mem_size;
-
-		/* compare results from other methods and take the greater */
-		if (boot_params.alt_mem_k < boot_params.screen_info.ext_mem_k) {
-			mem_size = boot_params.screen_info.ext_mem_k;
-			who = "BIOS-88";
-		} else {
-			mem_size = boot_params.alt_mem_k;
-			who = "BIOS-e801";
-		}
-
-		e820.nr_map = 0;
-		e820_add_region(0, LOWMEMSIZE(), E820_RAM);
-		e820_add_region(HIGH_MEMORY, mem_size << 10, E820_RAM);
-	}
-	return who;
+	return default_machine_specific_memory_setup();
 }

include/asm-x86/e820.h

@@ -102,6 +102,7 @@ extern u64 e820_hole_size(u64 start, u64 end);
 extern void finish_e820_parsing(void);
 extern void e820_reserve_resources(void);
 extern void setup_memory_map(void);
+extern char *default_machine_specific_memory_setup(void);
 extern char *machine_specific_memory_setup(void);
 extern char *memory_setup(void);
 
@@ -116,9 +117,7 @@ extern char *memory_setup(void);
 #ifdef __KERNEL__
 #include <linux/ioport.h>
 
-#ifdef CONFIG_X86_32
 #define HIGH_MEMORY	(1024*1024)
-#endif
 #endif /* __KERNEL__ */
 
 #endif  /* __ASM_E820_H */

include/asm-x86/setup.h

@@ -42,13 +42,14 @@ void vsmp_init(void);
  */
 extern struct boot_params boot_params;
 
-#ifdef __i386__
 /*
  * Do NOT EVER look at the BIOS memory size location.
  * It does not work on many machines.
  */
 #define LOWMEMSIZE()	(0x9f000)
 
+#ifdef __i386__
+
 void __init i386_start_kernel(void);
 
 extern unsigned long init_pg_tables_start;