[IA32] VIA C3 crypto/RNG bits

* Enable ACE (crypto) and RNG units on bootup.
* Do not disable RNG unit when unloading hw_random module.
* New bits listed in /proc/cpuinfo: rng_en, ace, ace_en
* Add ACE-associated constants to cpufeature.h

arch/i386/kernel/cpu/centaur.c

@@ -246,7 +246,15 @@ static void __init winchip2_protect_mcr(void)
 	lo&=~0x1C0;	/* blank bits 8-6 */
 	wrmsr(MSR_IDT_MCR_CTRL, lo, hi);
 }
-#endif
+#endif /* CONFIG_X86_OOSTORE */
+
+#define ACE_PRESENT	(1 << 6)
+#define ACE_ENABLED	(1 << 7)
+#define ACE_FCR		(1 << 28)	/* MSR_VIA_FCR */
+
+#define RNG_PRESENT	(1 << 2)
+#define RNG_ENABLED	(1 << 3)
+#define RNG_ENABLE	(1 << 6)	/* MSR_VIA_RNG */
 
 static void __init init_c3(struct cpuinfo_x86 *c)
 {
@@ -254,6 +262,24 @@ static void __init init_c3(struct cpuinfo_x86 *c)
 
 	/* Test for Centaur Extended Feature Flags presence */
 	if (cpuid_eax(0xC0000000) >= 0xC0000001) {
+		u32 tmp = cpuid_edx(0xC0000001);
+
+		/* enable ACE unit, if present and disabled */
+		if ((tmp & (ACE_PRESENT | ACE_ENABLED)) == ACE_PRESENT) {
+			rdmsr (MSR_VIA_FCR, lo, hi);
+			lo |= ACE_FCR;		/* enable ACE unit */
+			wrmsr (MSR_VIA_FCR, lo, hi);
+			printk(KERN_INFO "CPU: Enabled ACE h/w crypto\n");
+		}
+
+		/* enable RNG unit, if present and disabled */
+		if ((tmp & (RNG_PRESENT | RNG_ENABLED)) == RNG_PRESENT) {
+			rdmsr (MSR_VIA_RNG, lo, hi);
+			lo |= RNG_ENABLE;	/* enable RNG unit */
+			wrmsr (MSR_VIA_RNG, lo, hi);
+			printk(KERN_INFO "CPU: Enabled h/w RNG\n");
+		}
+
 		/* store Centaur Extended Feature Flags as
 		 * word 5 of the CPU capability bit array
 		 */

arch/i386/kernel/cpu/proc.c

@@ -50,7 +50,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 
 		/* VIA/Cyrix/Centaur-defined */
-		NULL, NULL, "xstore", NULL, NULL, NULL, NULL, NULL,
+		NULL, NULL, "rng", "rng_en", NULL, NULL, "ace", "ace_en",
 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,

drivers/char/hw_random.c

@@ -454,11 +454,7 @@ static int __init via_init(struct pci_dev *dev)
 
 static void via_cleanup(void)
 {
-	u32 lo, hi;
-
-	rdmsr(MSR_VIA_RNG, lo, hi);
-	lo &= ~VIA_RNG_ENABLE;
-	wrmsr(MSR_VIA_RNG, lo, hi);
+	/* do nothing */
 }
 
 

include/asm-i386/cpufeature.h

@@ -76,6 +76,9 @@
 
 /* VIA/Cyrix/Centaur-defined CPU features, CPUID level 0xC0000001, word 5 */
 #define X86_FEATURE_XSTORE	(5*32+ 2) /* on-CPU RNG present (xstore insn) */
+#define X86_FEATURE_XSTORE_EN	(5*32+ 3) /* on-CPU RNG enabled */
+#define X86_FEATURE_XCRYPT	(5*32+ 6) /* on-CPU crypto (xcrypt insn) */
+#define X86_FEATURE_XCRYPT_EN	(5*32+ 7) /* on-CPU crypto enabled */
 
 
 #define cpu_has(c, bit)		test_bit(bit, (c)->x86_capability)
@@ -101,6 +104,7 @@
 #define cpu_has_cyrix_arr	boot_cpu_has(X86_FEATURE_CYRIX_ARR)
 #define cpu_has_centaur_mcr	boot_cpu_has(X86_FEATURE_CENTAUR_MCR)
 #define cpu_has_xstore		boot_cpu_has(X86_FEATURE_XSTORE)
+#define cpu_has_xcrypt		boot_cpu_has(X86_FEATURE_XCRYPT)
 
 #endif /* __ASM_I386_CPUFEATURE_H */