MIPS: Set ELF AT_PLATFORM string for Loongson2 processors

Signed-off-by: Robert Millan <rmh@gnu.org>
Acked-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: David Daney <ddaney@caviumnetworks.com>
Cc: wu zhangjin <wuzhangjin@gmail.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/2302/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/cpu-probe.c

@@ -620,6 +620,16 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
 	case PRID_IMP_LOONGSON2:
 		c->cputype = CPU_LOONGSON2;
 		__cpu_name[cpu] = "ICT Loongson-2";
+
+		switch (c->processor_id & PRID_REV_MASK) {
+		case PRID_REV_LOONGSON2E:
+			set_elf_platform(cpu, "loongson2e");
+			break;
+		case PRID_REV_LOONGSON2F:
+			set_elf_platform(cpu, "loongson2f");
+			break;
+		}
+
 		c->isa_level = MIPS_CPU_ISA_III;
 		c->options = R4K_OPTS |
 			     MIPS_CPU_FPU | MIPS_CPU_LLSC |