diff --git a/arch/mips/include/asm/cpu-features.h b/arch/mips/include/asm/cpu-features.h
index e5ec8fcd8afa..9609812bc8f2 100644
--- a/arch/mips/include/asm/cpu-features.h
+++ b/arch/mips/include/asm/cpu-features.h
@@ -24,6 +24,16 @@
 #ifndef cpu_has_tlb
 #define cpu_has_tlb		(cpu_data[0].options & MIPS_CPU_TLB)
 #endif
+
+/*
+ * For the moment we don't consider R6000 and R8000 so we can assume that
+ * anything that doesn't support R4000-style exceptions and interrupts is
+ * R3000-like.  Users should still treat these two macro definitions as
+ * opaque.
+ */
+#ifndef cpu_has_3kex
+#define cpu_has_3kex		(!cpu_has_4kex)
+#endif
 #ifndef cpu_has_4kex
 #define cpu_has_4kex		(cpu_data[0].options & MIPS_CPU_4KEX)
 #endif
@@ -136,7 +146,6 @@
 #endif
 #endif
 
-# define cpu_has_mips_1		(cpu_data[0].isa_level & MIPS_CPU_ISA_I)
 #ifndef cpu_has_mips_2
 # define cpu_has_mips_2		(cpu_data[0].isa_level & MIPS_CPU_ISA_II)
 #endif
diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h
index dd86ab205483..632bbe5a79ea 100644
--- a/arch/mips/include/asm/cpu.h
+++ b/arch/mips/include/asm/cpu.h
@@ -282,18 +282,17 @@ enum cpu_type_enum {
  * ISA Level encodings
  *
  */
-#define MIPS_CPU_ISA_I		0x00000001
-#define MIPS_CPU_ISA_II		0x00000002
-#define MIPS_CPU_ISA_III	0x00000004
-#define MIPS_CPU_ISA_IV		0x00000008
-#define MIPS_CPU_ISA_V		0x00000010
-#define MIPS_CPU_ISA_M32R1	0x00000020
-#define MIPS_CPU_ISA_M32R2	0x00000040
-#define MIPS_CPU_ISA_M64R1	0x00000080
-#define MIPS_CPU_ISA_M64R2	0x00000100
+#define MIPS_CPU_ISA_II		0x00000001
+#define MIPS_CPU_ISA_III	0x00000002
+#define MIPS_CPU_ISA_IV		0x00000004
+#define MIPS_CPU_ISA_V		0x00000008
+#define MIPS_CPU_ISA_M32R1	0x00000010
+#define MIPS_CPU_ISA_M32R2	0x00000020
+#define MIPS_CPU_ISA_M64R1	0x00000040
+#define MIPS_CPU_ISA_M64R2	0x00000080
 
-#define MIPS_CPU_ISA_32BIT (MIPS_CPU_ISA_I | MIPS_CPU_ISA_II | \
-	MIPS_CPU_ISA_M32R1 | MIPS_CPU_ISA_M32R2)
+#define MIPS_CPU_ISA_32BIT (MIPS_CPU_ISA_II | MIPS_CPU_ISA_M32R1 | \
+	MIPS_CPU_ISA_M32R2)
 #define MIPS_CPU_ISA_64BIT (MIPS_CPU_ISA_III | MIPS_CPU_ISA_IV | \
 	MIPS_CPU_ISA_V | MIPS_CPU_ISA_M64R1 | MIPS_CPU_ISA_M64R2)
 
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 265c97da6619..f87039dbefe9 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -146,8 +146,7 @@ static void __cpuinit set_isa(struct cpuinfo_mips *c, unsigned int isa)
 	case MIPS_CPU_ISA_IV:
 		c->isa_level |= MIPS_CPU_ISA_IV;
 	case MIPS_CPU_ISA_III:
-		c->isa_level |= MIPS_CPU_ISA_I | MIPS_CPU_ISA_II |
-				MIPS_CPU_ISA_III;
+		c->isa_level |= MIPS_CPU_ISA_II | MIPS_CPU_ISA_III;
 		break;
 
 	case MIPS_CPU_ISA_M32R2:
@@ -156,8 +155,6 @@ static void __cpuinit set_isa(struct cpuinfo_mips *c, unsigned int isa)
 		c->isa_level |= MIPS_CPU_ISA_M32R1;
 	case MIPS_CPU_ISA_II:
 		c->isa_level |= MIPS_CPU_ISA_II;
-	case MIPS_CPU_ISA_I:
-		c->isa_level |= MIPS_CPU_ISA_I;
 		break;
 	}
 }
@@ -332,7 +329,6 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
 	case PRID_IMP_R2000:
 		c->cputype = CPU_R2000;
 		__cpu_name[cpu] = "R2000";
-		set_isa(c, MIPS_CPU_ISA_I);
 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
 			     MIPS_CPU_NOFPUEX;
 		if (__cpu_has_fpu())
@@ -352,7 +348,6 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
 			c->cputype = CPU_R3000;
 			__cpu_name[cpu] = "R3000";
 		}
-		set_isa(c, MIPS_CPU_ISA_I);
 		c->options = MIPS_CPU_TLB | MIPS_CPU_3K_CACHE |
 			     MIPS_CPU_NOFPUEX;
 		if (__cpu_has_fpu())
@@ -455,7 +450,6 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
 		break;
 	#endif
 	case PRID_IMP_TX39:
-		set_isa(c, MIPS_CPU_ISA_I);
 		c->options = MIPS_CPU_TLB | MIPS_CPU_TX39_CACHE;
 
 		if ((c->processor_id & 0xf0) == (PRID_REV_TX3927 & 0xf0)) {
diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c
index acb34373679e..8c58d8a84bf3 100644
--- a/arch/mips/kernel/proc.c
+++ b/arch/mips/kernel/proc.c
@@ -66,9 +66,7 @@ static int show_cpuinfo(struct seq_file *m, void *v)
 		seq_printf(m, "]\n");
 	}
 	if (cpu_has_mips_r) {
-		seq_printf(m, "isa\t\t\t:");
-		if (cpu_has_mips_1)
-			seq_printf(m, "%s", " mips1");
+		seq_printf(m, "isa\t\t\t: mips1");
 		if (cpu_has_mips_2)
 			seq_printf(m, "%s", " mips2");
 		if (cpu_has_mips_3)
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 142d2bede024..d97ea234e2d3 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -265,7 +265,7 @@ static void __show_regs(const struct pt_regs *regs)
 
 	printk("Status: %08x	", (uint32_t) regs->cp0_status);
 
-	if (current_cpu_data.isa_level == MIPS_CPU_ISA_I) {
+	if (cpu_has_3kex) {
 		if (regs->cp0_status & ST0_KUO)
 			printk("KUo ");
 		if (regs->cp0_status & ST0_IEO)
@@ -278,7 +278,7 @@ static void __show_regs(const struct pt_regs *regs)
 			printk("KUc ");
 		if (regs->cp0_status & ST0_IEC)
 			printk("IEc ");
-	} else {
+	} else if (cpu_has_4kex) {
 		if (regs->cp0_status & ST0_KX)
 			printk("KX ");
 		if (regs->cp0_status & ST0_SX)