x86, mce: Cleanup MCG definitions

Decode more magic constants and turn them into symbols.

[ Sort definitions bitwise, introduce MCG_EXT_CNT - HS ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/include/asm/mce.h

@@ -8,9 +8,13 @@
  * Machine Check support for x86
  */
 
-#define MCG_CTL_P	 (1ULL<<8)   /* MCG_CAP register available */
-#define MCG_EXT_P	 (1ULL<<9)   /* Extended registers available */
-#define MCG_CMCI_P	 (1ULL<<10)  /* CMCI supported */
+#define MCG_BANKCNT_MASK	0xff         /* Number of Banks */
+#define MCG_CTL_P		(1ULL<<8)    /* MCG_CAP register available */
+#define MCG_EXT_P		(1ULL<<9)    /* Extended registers available */
+#define MCG_CMCI_P		(1ULL<<10)   /* CMCI supported */
+#define MCG_EXT_CNT_MASK	0xff0000     /* Number of Extended registers */
+#define MCG_EXT_CNT_SHIFT	16
+#define MCG_EXT_CNT(c)		(((c) & MCG_EXT_CNT_MASK) >> MCG_EXT_CNT_SHIFT)
 
 #define MCG_STATUS_RIPV  (1ULL<<0)   /* restart ip valid */
 #define MCG_STATUS_EIPV  (1ULL<<1)   /* ip points to correct instruction */

arch/x86/kernel/cpu/mcheck/mce.c

@@ -569,7 +569,8 @@ static int mce_cap_init(void)
 	u64 cap;
 
 	rdmsrl(MSR_IA32_MCG_CAP, cap);
-	b = cap & 0xff;
+
+	b = cap & MCG_BANKCNT_MASK;
 	printk(KERN_INFO "mce: CPU supports %d MCE banks\n", b);
 
 	if (b > MAX_NR_BANKS) {
@@ -590,7 +591,7 @@ static int mce_cap_init(void)
 	}
 
 	/* Use accurate RIP reporting if available. */
-	if ((cap & (1<<9)) && ((cap >> 16) & 0xff) >= 9)
+	if ((cap & MCG_EXT_P) && MCG_EXT_CNT(cap) >= 9)
 		rip_msr = MSR_IA32_MCG_EIP;
 
 	return 0;