MIPS: traps: Dump the HTW registers on a MC exception

The HTW registers can be useful to debug a MC exception.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8400/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/traps.c

@@ -1432,6 +1432,11 @@ asmlinkage void do_mcheck(struct pt_regs *regs)
 		pr_err("EntryHi : %0*lx\n", field, read_c0_entryhi());
 		pr_err("EntryLo0: %0*lx\n", field, read_c0_entrylo0());
 		pr_err("EntryLo1: %0*lx\n", field, read_c0_entrylo1());
+		if (cpu_has_htw) {
+			pr_err("PWField : %0*lx\n", field, read_c0_pwfield());
+			pr_err("PWSize  : %0*lx\n", field, read_c0_pwsize());
+			pr_err("PWCtl   : %0x\n", read_c0_pwctl());
+		}
 		pr_err("\n");
 		dump_tlb_all();
 	}