MIPS: Loongson: Add basic Loongson-3 definition

Loongson-3 is a multi-core MIPS family CPU, it support MIPS64R2 fully.
Loongson-3 has the same IMP field (0x6300) as Loongson-2.

Loongson-3 has a hardware-maintained cache, system software doesn't
need to maintain coherency.

Loongson-3A is the first revision of Loongson-3, and it is the quad-
core version of Loongson-2G. Loongson-3A has a simplified version named
Loongson-2Gq, the main difference between Loongson-3A/2Gq is 3A has two
HyperTransport controller but 2Gq has only one. HT0 is used for cross-
chip interconnection and HT1 is used to link PCI bus. Therefore, 2Gq
cannot support NUMA but 3A can. For software, Loongson-2Gq is simply
identified as Loongson-3A.

Exsisting Loongson family CPUs:
Loongson-1: Loongson-1A, Loongson-1B, they are 32-bit MIPS CPUs.
Loongson-2: Loongson-2E, Loongson-2F, Loongson-2G, they are 64-bit
            single-core MIPS CPUs.
Loongson-3: Loongson-3A(including so-called Loongson-2Gq), they are
            64-bit multi-core MIPS CPUs.

Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Hongliang Tao <taohl@lemote.com>
Signed-off-by: Hua Yan <yanh@lemote.com>
Tested-by: Alex Smith <alex.smith@imgtec.com>
Reviewed-by: Alex Smith <alex.smith@imgtec.com>
Cc: John Crispin <john@phrozen.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang <zhangfx@lemote.com>
Cc: Zhangjin Wu <wuzhangjin@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/6629/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h
index 01d757c..530eb8b 100644
--- a/arch/mips/include/asm/cpu.h
+++ b/arch/mips/include/asm/cpu.h
@@ -231,6 +231,7 @@
 #define PRID_REV_LOONGSON1B	0x0020
 #define PRID_REV_LOONGSON2E	0x0002
 #define PRID_REV_LOONGSON2F	0x0003
+#define PRID_REV_LOONGSON3A	0x0005
 
 /*
  * Older processors used to encode processor version and revision in two
@@ -304,8 +305,8 @@
 	 * MIPS64 class processors
 	 */
 	CPU_5KC, CPU_5KE, CPU_20KC, CPU_25KF, CPU_SB1, CPU_SB1A, CPU_LOONGSON2,
-	CPU_CAVIUM_OCTEON, CPU_CAVIUM_OCTEON_PLUS, CPU_CAVIUM_OCTEON2,
-	CPU_CAVIUM_OCTEON3, CPU_XLR, CPU_XLP,
+	CPU_LOONGSON3, CPU_CAVIUM_OCTEON, CPU_CAVIUM_OCTEON_PLUS,
+	CPU_CAVIUM_OCTEON2, CPU_CAVIUM_OCTEON3, CPU_XLR, CPU_XLP,
 
 	CPU_LAST
 };