MIPS: Loongson: Add basic Loongson-3 CPU support

Basic Loongson-3 CPU support include CPU probing and TLB/cache
initializing.

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/6630
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index 3e53f1b..1c74a6a 100644
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -398,6 +398,7 @@
 {
 	switch (current_cpu_type()) {
 	case CPU_LOONGSON2:
+	case CPU_LOONGSON3:
 	case CPU_R4000SC:
 	case CPU_R4000MC:
 	case CPU_R4400SC:
@@ -1066,6 +1067,33 @@
 		c->dcache.waybit = 0;
 		break;
 
+	case CPU_LOONGSON3:
+		config1 = read_c0_config1();
+		lsize = (config1 >> 19) & 7;
+		if (lsize)
+			c->icache.linesz = 2 << lsize;
+		else
+			c->icache.linesz = 0;
+		c->icache.sets = 64 << ((config1 >> 22) & 7);
+		c->icache.ways = 1 + ((config1 >> 16) & 7);
+		icache_size = c->icache.sets *
+					  c->icache.ways *
+					  c->icache.linesz;
+		c->icache.waybit = 0;
+
+		lsize = (config1 >> 10) & 7;
+		if (lsize)
+			c->dcache.linesz = 2 << lsize;
+		else
+			c->dcache.linesz = 0;
+		c->dcache.sets = 64 << ((config1 >> 13) & 7);
+		c->dcache.ways = 1 + ((config1 >> 7) & 7);
+		dcache_size = c->dcache.sets *
+					  c->dcache.ways *
+					  c->dcache.linesz;
+		c->dcache.waybit = 0;
+		break;
+
 	default:
 		if (!(config & MIPS_CONF_M))
 			panic("Don't know how to probe P-caches on this cpu.");
@@ -1303,6 +1331,33 @@
 	c->options |= MIPS_CPU_INCLUSIVE_CACHES;
 }
 
+static void __init loongson3_sc_init(void)
+{
+	struct cpuinfo_mips *c = &current_cpu_data;
+	unsigned int config2, lsize;
+
+	config2 = read_c0_config2();
+	lsize = (config2 >> 4) & 15;
+	if (lsize)
+		c->scache.linesz = 2 << lsize;
+	else
+		c->scache.linesz = 0;
+	c->scache.sets = 64 << ((config2 >> 8) & 15);
+	c->scache.ways = 1 + (config2 & 15);
+
+	scache_size = c->scache.sets *
+				  c->scache.ways *
+				  c->scache.linesz;
+	/* Loongson-3 has 4 cores, 1MB scache for each. scaches are shared */
+	scache_size *= 4;
+	c->scache.waybit = 0;
+	pr_info("Unified secondary cache %ldkB %s, linesize %d bytes.\n",
+	       scache_size >> 10, way_string[c->scache.ways], c->scache.linesz);
+	if (scache_size)
+		c->options |= MIPS_CPU_INCLUSIVE_CACHES;
+	return;
+}
+
 extern int r5k_sc_init(void);
 extern int rm7k_sc_init(void);
 extern int mips_sc_init(void);
@@ -1355,6 +1410,10 @@
 		loongson2_sc_init();
 		return;
 
+	case CPU_LOONGSON3:
+		loongson3_sc_init();
+		return;
+
 	case CPU_XLP:
 		/* don't need to worry about L2, fully coherent */
 		return;