x86/boot: Simplify the detect_memory*() control flow

The return values of these functions are not used - so simplify the functions.

No change in functionality.

[ mingo: Simplified the changelog. ]

Suggested: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Jordan Borgner <mail@jordan-borgner.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20181102145622.zjx2t3mdu3rv6sgy@JordanDesktopSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/boot/boot.h

@@ -309,7 +309,7 @@ void query_edd(void);
 void __attribute__((noreturn)) die(void);
 
 /* memory.c */
-int detect_memory(void);
+void detect_memory(void);
 
 /* pm.c */
 void __attribute__((noreturn)) go_to_protected_mode(void);

arch/x86/boot/memory.c

@@ -17,7 +17,7 @@
 
 #define SMAP	0x534d4150	/* ASCII "SMAP" */
 
-static int detect_memory_e820(void)
+static void detect_memory_e820(void)
 {
 	int count = 0;
 	struct biosregs ireg, oreg;
@@ -68,10 +68,10 @@ static int detect_memory_e820(void)
 		count++;
 	} while (ireg.ebx && count < ARRAY_SIZE(boot_params.e820_table));
 
-	return boot_params.e820_entries = count;
+	boot_params.e820_entries = count;
 }
 
-static int detect_memory_e801(void)
+static void detect_memory_e801(void)
 {
 	struct biosregs ireg, oreg;
 
@@ -80,7 +80,7 @@ static int detect_memory_e801(void)
 	intcall(0x15, &ireg, &oreg);
 
 	if (oreg.eflags & X86_EFLAGS_CF)
-		return -1;
+		return;
 
 	/* Do we really need to do this? */
 	if (oreg.cx || oreg.dx) {
@@ -89,7 +89,7 @@ static int detect_memory_e801(void)
 	}
 
 	if (oreg.ax > 15*1024) {
-		return -1;	/* Bogus! */
+		return;	/* Bogus! */
 	} else if (oreg.ax == 15*1024) {
 		boot_params.alt_mem_k = (oreg.bx << 6) + oreg.ax;
 	} else {
@@ -102,11 +102,9 @@ static int detect_memory_e801(void)
 		 */
 		boot_params.alt_mem_k = oreg.ax;
 	}
-
-	return 0;
 }
 
-static int detect_memory_88(void)
+static void detect_memory_88(void)
 {
 	struct biosregs ireg, oreg;
 
@@ -115,22 +113,13 @@ static int detect_memory_88(void)
 	intcall(0x15, &ireg, &oreg);
 
 	boot_params.screen_info.ext_mem_k = oreg.ax;
-
-	return -(oreg.eflags & X86_EFLAGS_CF); /* 0 or -1 */
 }
 
-int detect_memory(void)
+void detect_memory(void)
 {
-	int err = -1;
-
-	if (detect_memory_e820() > 0)
-		err = 0;
-
-	if (!detect_memory_e801())
-		err = 0;
+	detect_memory_e820();
 
-	if (!detect_memory_88())
-		err = 0;
+	detect_memory_e801();
 
-	return err;
+	detect_memory_88();
 }