MIPS: features: Add initial support for TLBINVF capable cores

New Aptiv cores support the TLBINVF instruction for flushing
the VTLB.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6130/

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

@@ -20,6 +20,9 @@
 #ifndef cpu_has_tlb
 #define cpu_has_tlb		(cpu_data[0].options & MIPS_CPU_TLB)
 #endif
+#ifndef cpu_has_tlbinv
+#define cpu_has_tlbinv		(cpu_data[0].options & MIPS_CPU_TLBINV)
+#endif
 
 /*
  * For the moment we don't consider R6000 and R8000 so we can assume that

arch/mips/include/asm/cpu.h

@@ -351,6 +351,7 @@ enum cpu_type_enum {
 #define MIPS_CPU_PCI		0x00400000 /* CPU has Perf Ctr Int indicator */
 #define MIPS_CPU_RIXI		0x00800000 /* CPU has TLB Read/eXec Inhibit */
 #define MIPS_CPU_MICROMIPS	0x01000000 /* CPU has microMIPS capability */
+#define MIPS_CPU_TLBINV		0x02000000 /* CPU supports TLBINV/F */
 
 /*
  * CPU ASE encodings

arch/mips/kernel/cpu-probe.c

@@ -286,6 +286,11 @@ static inline unsigned int decode_config4(struct cpuinfo_mips *c)
 	    && cpu_has_tlb)
 		c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
 
+	if (cpu_has_tlb) {
+		if (((config4 & MIPS_CONF4_IE) >> 29) == 2)
+			c->options |= MIPS_CPU_TLBINV;
+	}
+
 	c->kscratch_mask = (config4 >> 16) & 0xff;
 
 	return config4 & MIPS_CONF_M;