MIPS: cpu: Add new cpu option for Hardware Table Walker.

Moreover, report hardware page table walker support as 'htw' in the ASE
list of /proc/cpuinfo, if the core implements this feature.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7334/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

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

@@ -29,6 +29,9 @@
 #ifndef cpu_has_eva
 #define cpu_has_eva		(cpu_data[0].options & MIPS_CPU_EVA)
 #endif
+#ifndef cpu_has_htw
+#define cpu_has_htw		(cpu_data[0].options & MIPS_CPU_HTW)
+#endif
 
 /*
  * For the moment we don't consider R6000 and R8000 so we can assume that

arch/mips/include/asm/cpu.h

@@ -365,6 +365,7 @@ enum cpu_type_enum {
 #define MIPS_CPU_TLBINV		0x02000000ull /* CPU supports TLBINV/F */
 #define MIPS_CPU_SEGMENTS	0x04000000ull /* CPU supports Segmentation Control registers */
 #define MIPS_CPU_EVA		0x80000000ull /* CPU supports Enhanced Virtual Addressing */
+#define MIPS_CPU_HTW		0x100000000ull /* CPU support Hardware Page Table Walker */
 
 /*
  * CPU ASE encodings

arch/mips/kernel/proc.c

@@ -113,6 +113,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 	if (cpu_has_vz)		seq_printf(m, "%s", " vz");
 	if (cpu_has_msa)	seq_printf(m, "%s", " msa");
 	if (cpu_has_eva)	seq_printf(m, "%s", " eva");
+	if (cpu_has_htw)	seq_printf(m, "%s", " htw");
 	seq_printf(m, "\n");
 
 	if (cpu_has_mmips) {