MIPS: Add CPU support for Loongson1B

Loongson 1B is a 32-bit SoC designed by Institute of Computing Technology
(ICT) and the Chinese Academy of Sciences (CAS), which implements the
MIPS32 release 2 instruction set.

[ralf@linux-mips.org: But which is not strictly a MIPS32 compliant device
which also is why it identifies itself with the Legacy Vendor ID in the
PrID register.  When applying the patch I shoveled some code around to
keep things in alphabetical order and avoid forward declarations.]

Signed-off-by: Kelvin Cheung <keguang.zhang@gmail.com>
Cc: To: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: wuzhangjin@gmail.com
Cc: zhzhl555@gmail.com
Cc: Kelvin Cheung <keguang.zhang@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/3976/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

7 files changed, 171 insertions, 144 deletions

diff --git a/arch/mips/include/asm/cpu.h b/arch/mips/include/asm/cpu.h
index 95e40c1e8ed1..f21b7c04e95a 100644
--- a/arch/mips/include/asm/cpu.h
+++ b/arch/mips/include/asm/cpu.h
@@ -197,6 +197,7 @@
 #define PRID_REV_VR4181A        0x0070  /* Same as VR4122 */
 #define PRID_REV_VR4130         0x0080
 #define PRID_REV_34K_V1_0_2     0x0022
+#define PRID_REV_LOONGSON1B     0x0020
 #define PRID_REV_LOONGSON2E     0x0002
 #define PRID_REV_LOONGSON2F     0x0003
 
@@ -261,7 +262,7 @@ enum cpu_type_enum {
          */
         CPU_4KC, CPU_4KEC, CPU_4KSC, CPU_24K, CPU_34K, CPU_1004K, CPU_74K,
         CPU_ALCHEMY, CPU_PR4450, CPU_BMIPS32, CPU_BMIPS3300, CPU_BMIPS4350,
-        CPU_BMIPS4380, CPU_BMIPS5000, CPU_JZRISC, CPU_M14KC,
+        CPU_BMIPS4380, CPU_BMIPS5000, CPU_JZRISC, CPU_LOONGSON1, CPU_M14KC,
 
         /*
          * MIPS64 class processors
diff --git a/arch/mips/include/asm/module.h b/arch/mips/include/asm/module.h
index 530008048c62..7531ecd654d6 100644
--- a/arch/mips/include/asm/module.h
+++ b/arch/mips/include/asm/module.h
@@ -117,6 +117,8 @@ search_module_dbetables(unsigned long addr)
 #define MODULE_PROC_FAMILY "RM9000 "
 #elif defined CONFIG_CPU_SB1
 #define MODULE_PROC_FAMILY "SB1 "
+#elif defined CONFIG_CPU_LOONGSON1
+#define MODULE_PROC_FAMILY "LOONGSON1 "
 #elif defined CONFIG_CPU_LOONGSON2
 #define MODULE_PROC_FAMILY "LOONGSON2 "
 #elif defined CONFIG_CPU_CAVIUM_OCTEON
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index f4630e1082ab..1b51046191e8 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -190,6 +190,7 @@ void __init check_wait(void)
         case CPU_CAVIUM_OCTEON_PLUS:
         case CPU_CAVIUM_OCTEON2:
         case CPU_JZRISC:
+        case CPU_LOONGSON1:
         case CPU_XLR:
         case CPU_XLP:
                 cpu_wait = r4k_wait;
@@ -330,6 +331,154 @@ static inline void cpu_probe_vmbits(struct cpuinfo_mips *c)
 #endif
 }
 
+static char unknown_isa[] __cpuinitdata = KERN_ERR \
+        "Unsupported ISA type, c0.config0: %d.";
+
+static inline unsigned int decode_config0(struct cpuinfo_mips *c)
+{
+        unsigned int config0;
+        int isa;
+
+        config0 = read_c0_config();
+
+        if (((config0 & MIPS_CONF_MT) >> 7) == 1)
+                c->options |= MIPS_CPU_TLB;
+        isa = (config0 & MIPS_CONF_AT) >> 13;
+        switch (isa) {
+        case 0:
+                switch ((config0 & MIPS_CONF_AR) >> 10) {
+                case 0:
+                        c->isa_level = MIPS_CPU_ISA_M32R1;
+                        break;
+                case 1:
+                        c->isa_level = MIPS_CPU_ISA_M32R2;
+                        break;
+                default:
+                        goto unknown;
+                }
+                break;
+        case 2:
+                switch ((config0 & MIPS_CONF_AR) >> 10) {
+                case 0:
+                        c->isa_level = MIPS_CPU_ISA_M64R1;
+                        break;
+                case 1:
+                        c->isa_level = MIPS_CPU_ISA_M64R2;
+                        break;
+                default:
+                        goto unknown;
+                }
+                break;
+        default:
+                goto unknown;
+        }
+
+        return config0 & MIPS_CONF_M;
+
+unknown:
+        panic(unknown_isa, config0);
+}
+
+static inline unsigned int decode_config1(struct cpuinfo_mips *c)
+{
+        unsigned int config1;
+
+        config1 = read_c0_config1();
+
+        if (config1 & MIPS_CONF1_MD)
+                c->ases |= MIPS_ASE_MDMX;
+        if (config1 & MIPS_CONF1_WR)
+                c->options |= MIPS_CPU_WATCH;
+        if (config1 & MIPS_CONF1_CA)
+                c->ases |= MIPS_ASE_MIPS16;
+        if (config1 & MIPS_CONF1_EP)
+                c->options |= MIPS_CPU_EJTAG;
+        if (config1 & MIPS_CONF1_FP) {
+                c->options |= MIPS_CPU_FPU;
+                c->options |= MIPS_CPU_32FPR;
+        }
+        if (cpu_has_tlb)
+                c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
+
+        return config1 & MIPS_CONF_M;
+}
+
+static inline unsigned int decode_config2(struct cpuinfo_mips *c)
+{
+        unsigned int config2;
+
+        config2 = read_c0_config2();
+
+        if (config2 & MIPS_CONF2_SL)
+                c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
+
+        return config2 & MIPS_CONF_M;
+}
+
+static inline unsigned int decode_config3(struct cpuinfo_mips *c)
+{
+        unsigned int config3;
+
+        config3 = read_c0_config3();
+
+        if (config3 & MIPS_CONF3_SM)
+                c->ases |= MIPS_ASE_SMARTMIPS;
+        if (config3 & MIPS_CONF3_DSP)
+                c->ases |= MIPS_ASE_DSP;
+        if (config3 & MIPS_CONF3_VINT)
+                c->options |= MIPS_CPU_VINT;
+        if (config3 & MIPS_CONF3_VEIC)
+                c->options |= MIPS_CPU_VEIC;
+        if (config3 & MIPS_CONF3_MT)
+                c->ases |= MIPS_ASE_MIPSMT;
+        if (config3 & MIPS_CONF3_ULRI)
+                c->options |= MIPS_CPU_ULRI;
+
+        return config3 & MIPS_CONF_M;
+}
+
+static inline unsigned int decode_config4(struct cpuinfo_mips *c)
+{
+        unsigned int config4;
+
+        config4 = read_c0_config4();
+
+        if ((config4 & MIPS_CONF4_MMUEXTDEF) == MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT
+            && cpu_has_tlb)
+                c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
+
+        c->kscratch_mask = (config4 >> 16) & 0xff;
+
+        return config4 & MIPS_CONF_M;
+}
+
+static void __cpuinit decode_configs(struct cpuinfo_mips *c)
+{
+        int ok;
+
+        /* MIPS32 or MIPS64 compliant CPU.  */
+        c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
+                     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
+
+        c->scache.flags = MIPS_CACHE_NOT_PRESENT;
+
+        ok = decode_config0(c);                 /* Read Config registers.  */
+        BUG_ON(!ok);                            /* Arch spec violation!  */
+        if (ok)
+                ok = decode_config1(c);
+        if (ok)
+                ok = decode_config2(c);
+        if (ok)
+                ok = decode_config3(c);
+        if (ok)
+                ok = decode_config4(c);
+
+        mips_probe_watch_registers(c);
+
+        if (cpu_has_mips_r2)
+                c->core = read_c0_ebase() & 0x3ff;
+}
+
 #define R4K_OPTS (MIPS_CPU_TLB | MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE \
                 | MIPS_CPU_COUNTER)
 
@@ -638,155 +787,19 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
                              MIPS_CPU_32FPR;
                 c->tlbsize = 64;
                 break;
-        }
-}
-
-static char unknown_isa[] __cpuinitdata = KERN_ERR \
-        "Unsupported ISA type, c0.config0: %d.";
+        case PRID_IMP_LOONGSON1:
+                decode_configs(c);
 
-static inline unsigned int decode_config0(struct cpuinfo_mips *c)
-{
-        unsigned int config0;
-        int isa;
+                c->cputype = CPU_LOONGSON1;
 
-        config0 = read_c0_config();
-
-        if (((config0 & MIPS_CONF_MT) >> 7) == 1)
-                c->options |= MIPS_CPU_TLB;
-        isa = (config0 & MIPS_CONF_AT) >> 13;
-        switch (isa) {
-        case 0:
-                switch ((config0 & MIPS_CONF_AR) >> 10) {
-                case 0:
-                        c->isa_level = MIPS_CPU_ISA_M32R1;
-                        break;
-                case 1:
-                        c->isa_level = MIPS_CPU_ISA_M32R2;
+                switch (c->processor_id & PRID_REV_MASK) {
+                case PRID_REV_LOONGSON1B:
+                        __cpu_name[cpu] = "Loongson 1B";
                         break;
-                default:
-                        goto unknown;
                 }
-                break;
-        case 2:
-                switch ((config0 & MIPS_CONF_AR) >> 10) {
-                case 0:
-                        c->isa_level = MIPS_CPU_ISA_M64R1;
-                        break;
-                case 1:
-                        c->isa_level = MIPS_CPU_ISA_M64R2;
-                        break;
-                default:
-                        goto unknown;
-                }
-                break;
-        default:
-                goto unknown;
-        }
-
-        return config0 & MIPS_CONF_M;
-
-unknown:
-        panic(unknown_isa, config0);
-}
 
-static inline unsigned int decode_config1(struct cpuinfo_mips *c)
-{
-        unsigned int config1;
-
-        config1 = read_c0_config1();
-
-        if (config1 & MIPS_CONF1_MD)
-                c->ases |= MIPS_ASE_MDMX;
-        if (config1 & MIPS_CONF1_WR)
-                c->options |= MIPS_CPU_WATCH;
-        if (config1 & MIPS_CONF1_CA)
-                c->ases |= MIPS_ASE_MIPS16;
-        if (config1 & MIPS_CONF1_EP)
-                c->options |= MIPS_CPU_EJTAG;
-        if (config1 & MIPS_CONF1_FP) {
-                c->options |= MIPS_CPU_FPU;
-                c->options |= MIPS_CPU_32FPR;
+                break;
         }
-        if (cpu_has_tlb)
-                c->tlbsize = ((config1 & MIPS_CONF1_TLBS) >> 25) + 1;
-
-        return config1 & MIPS_CONF_M;
-}
-
-static inline unsigned int decode_config2(struct cpuinfo_mips *c)
-{
-        unsigned int config2;
-
-        config2 = read_c0_config2();
-
-        if (config2 & MIPS_CONF2_SL)
-                c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT;
-
-        return config2 & MIPS_CONF_M;
-}
-
-static inline unsigned int decode_config3(struct cpuinfo_mips *c)
-{
-        unsigned int config3;
-
-        config3 = read_c0_config3();
-
-        if (config3 & MIPS_CONF3_SM)
-                c->ases |= MIPS_ASE_SMARTMIPS;
-        if (config3 & MIPS_CONF3_DSP)
-                c->ases |= MIPS_ASE_DSP;
-        if (config3 & MIPS_CONF3_VINT)
-                c->options |= MIPS_CPU_VINT;
-        if (config3 & MIPS_CONF3_VEIC)
-                c->options |= MIPS_CPU_VEIC;
-        if (config3 & MIPS_CONF3_MT)
-                c->ases |= MIPS_ASE_MIPSMT;
-        if (config3 & MIPS_CONF3_ULRI)
-                c->options |= MIPS_CPU_ULRI;
-
-        return config3 & MIPS_CONF_M;
-}
-
-static inline unsigned int decode_config4(struct cpuinfo_mips *c)
-{
-        unsigned int config4;
-
-        config4 = read_c0_config4();
-
-        if ((config4 & MIPS_CONF4_MMUEXTDEF) == MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT
-            && cpu_has_tlb)
-                c->tlbsize += (config4 & MIPS_CONF4_MMUSIZEEXT) * 0x40;
-
-        c->kscratch_mask = (config4 >> 16) & 0xff;
-
-        return config4 & MIPS_CONF_M;
-}
-
-static void __cpuinit decode_configs(struct cpuinfo_mips *c)
-{
-        int ok;
-
-        /* MIPS32 or MIPS64 compliant CPU.  */
-        c->options = MIPS_CPU_4KEX | MIPS_CPU_4K_CACHE | MIPS_CPU_COUNTER |
-                     MIPS_CPU_DIVEC | MIPS_CPU_LLSC | MIPS_CPU_MCHECK;
-
-        c->scache.flags = MIPS_CACHE_NOT_PRESENT;
-
-        ok = decode_config0(c);                 /* Read Config registers.  */
-        BUG_ON(!ok);                            /* Arch spec violation!  */
-        if (ok)
-                ok = decode_config1(c);
-        if (ok)
-                ok = decode_config2(c);
-        if (ok)
-                ok = decode_config3(c);
-        if (ok)
-                ok = decode_config4(c);
-
-        mips_probe_watch_registers(c);
-
-        if (cpu_has_mips_r2)
-                c->core = read_c0_ebase() & 0x3ff;
 }
 
 static inline void cpu_probe_mips(struct cpuinfo_mips *c, unsigned int cpu)
diff --git a/arch/mips/kernel/perf_event_mipsxx.c b/arch/mips/kernel/perf_event_mipsxx.c
index eb5e394a4650..2f28d3b55687 100644
--- a/arch/mips/kernel/perf_event_mipsxx.c
+++ b/arch/mips/kernel/perf_event_mipsxx.c
@@ -1559,6 +1559,11 @@ init_hw_perf_events(void)
                 mipspmu.general_event_map = &mipsxxcore_event_map;
                 mipspmu.cache_event_map = &mipsxxcore_cache_map;
                 break;
+        case CPU_LOONGSON1:
+                mipspmu.name = "mips/loongson1";
+                mipspmu.general_event_map = &mipsxxcore_event_map;
+                mipspmu.cache_event_map = &mipsxxcore_cache_map;
+                break;
         case CPU_CAVIUM_OCTEON:
         case CPU_CAVIUM_OCTEON_PLUS:
         case CPU_CAVIUM_OCTEON2:
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index c3c293543703..9be3df1fa8a4 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -1253,6 +1253,7 @@ static inline void parity_protection_init(void)
 
         case CPU_5KC:
         case CPU_5KE:
+        case CPU_LOONGSON1:
                 write_c0_ecc(0x80000000);
                 back_to_back_c0_hazard();
                 /* Set the PE bit (bit 31) in the c0_errctl register. */
diff --git a/arch/mips/oprofile/common.c b/arch/mips/oprofile/common.c
index b6e378211a2c..f80480a5a032 100644
--- a/arch/mips/oprofile/common.c
+++ b/arch/mips/oprofile/common.c
@@ -85,6 +85,7 @@ int __init oprofile_arch_init(struct oprofile_operations *ops)
         case CPU_34K:
         case CPU_1004K:
         case CPU_74K:
+        case CPU_LOONGSON1:
         case CPU_SB1:
         case CPU_SB1A:
         case CPU_R10000:
diff --git a/arch/mips/oprofile/op_model_mipsxx.c b/arch/mips/oprofile/op_model_mipsxx.c
index 4d80a856048d..056da6224163 100644
--- a/arch/mips/oprofile/op_model_mipsxx.c
+++ b/arch/mips/oprofile/op_model_mipsxx.c
@@ -374,6 +374,10 @@ static int __init mipsxx_init(void)
                 op_model_mipsxx_ops.cpu_type = "mips/sb1";
                 break;
 
+        case CPU_LOONGSON1:
+                op_model_mipsxx_ops.cpu_type = "mips/loongson1";
+                break;
+
         default:
                 printk(KERN_ERR "Profiling unsupported for this CPU\n");