MIPS: Probe for and report hardware virtualization support.

The presence of the MIPS Virtualization Application-Specific Extension
is indicated by CP0_Config3[23].  Probe for this and report it in
/proc/cpuinfo.
Signed-off-by: David Daney <david.daney@cavium.com>
Patchwork: http://patchwork.linux-mips.org/patch/4904/Signed-off-by: John Crispin <blogic@openwrt.org>

arch/mips/include/asm/cpu-features.h

@@ -263,4 +263,8 @@
 #define cpu_has_perf_cntr_intr_bit	(cpu_data[0].options & MIPS_CPU_PCI)
 #endif
 
+#ifndef cpu_has_vz
+#define cpu_has_vz		(cpu_data[0].ases & MIPS_ASE_VZ)
+#endif
+
 #endif /* __ASM_CPU_FEATURES_H */

arch/mips/include/asm/cpu.h

@@ -336,6 +336,6 @@ enum cpu_type_enum {
 #define MIPS_ASE_DSP		0x00000010 /* Signal Processing ASE */
 #define MIPS_ASE_MIPSMT		0x00000020 /* CPU supports MIPS MT */
 #define MIPS_ASE_DSP2P		0x00000040 /* Signal Processing ASE Rev 2 */
-
+#define MIPS_ASE_VZ		0x00000080 /* Virtualization ASE */
 
 #endif /* _ASM_CPU_H */

arch/mips/include/asm/mipsregs.h

@@ -596,6 +596,7 @@
 #define MIPS_CONF3_RXI		(_ULCAST_(1) << 12)
 #define MIPS_CONF3_ULRI		(_ULCAST_(1) << 13)
 #define MIPS_CONF3_ISA		(_ULCAST_(3) << 14)
+#define MIPS_CONF3_VZ		(_ULCAST_(1) << 23)
 
 #define MIPS_CONF4_MMUSIZEEXT	(_ULCAST_(255) << 0)
 #define MIPS_CONF4_MMUEXTDEF	(_ULCAST_(3) << 14)

arch/mips/kernel/cpu-probe.c

@@ -442,6 +442,8 @@ static inline unsigned int decode_config3(struct cpuinfo_mips *c)
 		c->options |= MIPS_CPU_ULRI;
 	if (config3 & MIPS_CONF3_ISA)
 		c->options |= MIPS_CPU_MICROMIPS;
+	if (config3 & MIPS_CONF3_VZ)
+		c->ases |= MIPS_ASE_VZ;
 
 	return config3 & MIPS_CONF_M;
 }

arch/mips/kernel/proc.c

@@ -74,6 +74,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 	if (cpu_has_dsp2)	seq_printf(m, "%s", " dsp2");
 	if (cpu_has_mipsmt)	seq_printf(m, "%s", " mt");
 	if (cpu_has_mmips)	seq_printf(m, "%s", " micromips");
+	if (cpu_has_vz)		seq_printf(m, "%s", " vz");
 	seq_printf(m, "\n");
 
 	seq_printf(m, "shadow register sets\t: %d\n",