1 files changed, 67 insertions, 4 deletions

diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index dc49cf30c2db..5342674842f5 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -69,6 +69,63 @@ static int __init htw_disable(char *s)
 
 __setup("nohtw", htw_disable);
 
+static int mips_ftlb_disabled;
+static int mips_has_ftlb_configured;
+
+static void set_ftlb_enable(struct cpuinfo_mips *c, int enable);
+
+static int __init ftlb_disable(char *s)
+{
+        unsigned int config4, mmuextdef;
+
+        /*
+         * If the core hasn't done any FTLB configuration, there is nothing
+         * for us to do here.
+         */
+        if (!mips_has_ftlb_configured)
+                return 1;
+
+        /* Disable it in the boot cpu */
+        set_ftlb_enable(&cpu_data[0], 0);
+
+        back_to_back_c0_hazard();
+
+        config4 = read_c0_config4();
+
+        /* Check that FTLB has been disabled */
+        mmuextdef = config4 & MIPS_CONF4_MMUEXTDEF;
+        /* MMUSIZEEXT == VTLB ON, FTLB OFF */
+        if (mmuextdef == MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT) {
+                /* This should never happen */
+                pr_warn("FTLB could not be disabled!\n");
+                return 1;
+        }
+
+        mips_ftlb_disabled = 1;
+        mips_has_ftlb_configured = 0;
+
+        /*
+         * noftlb is mainly used for debug purposes so print
+         * an informative message instead of using pr_debug()
+         */
+        pr_info("FTLB has been disabled\n");
+
+        /*
+         * Some of these bits are duplicated in the decode_config4.
+         * MIPS_CONF4_MMUEXTDEF_MMUSIZEEXT is the only possible case
+         * once FTLB has been disabled so undo what decode_config4 did.
+         */
+        cpu_data[0].tlbsize -= cpu_data[0].tlbsizeftlbways *
+                               cpu_data[0].tlbsizeftlbsets;
+        cpu_data[0].tlbsizeftlbsets = 0;
+        cpu_data[0].tlbsizeftlbways = 0;
+
+        return 1;
+}
+
+__setup("noftlb", ftlb_disable);
+
+
 static inline void check_errata(void)
 {
         struct cpuinfo_mips *c = &current_cpu_data;
@@ -140,7 +197,7 @@ static inline unsigned long cpu_get_fpu_id(void)
  */
 static inline int __cpu_has_fpu(void)
 {
-        return ((cpu_get_fpu_id() & FPIR_IMP_MASK) != FPIR_IMP_NONE);
+        return (cpu_get_fpu_id() & FPIR_IMP_MASK) != FPIR_IMP_NONE;
 }
 
 static inline unsigned long cpu_get_msa_id(void)
@@ -399,6 +456,8 @@ static inline unsigned int decode_config4(struct cpuinfo_mips *c)
                         ftlb_page = MIPS_CONF4_VFTLBPAGESIZE;
                         /* fall through */
                 case MIPS_CONF4_MMUEXTDEF_FTLBSIZEEXT:
+                        if (mips_ftlb_disabled)
+                                break;
                         newcf4 = (config4 & ~ftlb_page) |
                                 (page_size_ftlb(mmuextdef) <<
                                  MIPS_CONF4_FTLBPAGESIZE_SHIFT);
@@ -418,6 +477,7 @@ static inline unsigned int decode_config4(struct cpuinfo_mips *c)
                         c->tlbsizeftlbways = ((config4 & MIPS_CONF4_FTLBWAYS) >>
                                               MIPS_CONF4_FTLBWAYS_SHIFT) + 2;
                         c->tlbsize += c->tlbsizeftlbways * c->tlbsizeftlbsets;
+                        mips_has_ftlb_configured = 1;
                         break;
                 }
         }
@@ -432,7 +492,7 @@ static inline unsigned int decode_config5(struct cpuinfo_mips *c)
         unsigned int config5;
 
         config5 = read_c0_config5();
-        config5 &= ~MIPS_CONF5_UFR;
+        config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
         write_c0_config5(config5);
 
         if (config5 & MIPS_CONF5_EVA)
@@ -453,8 +513,8 @@ static void decode_configs(struct cpuinfo_mips *c)
 
         c->scache.flags = MIPS_CACHE_NOT_PRESENT;
 
-        /* Enable FTLB if present */
-        set_ftlb_enable(c, 1);
+        /* Enable FTLB if present and not disabled */
+        set_ftlb_enable(c, !mips_ftlb_disabled);
 
         ok = decode_config0(c);                 /* Read Config registers.  */
         BUG_ON(!ok);                            /* Arch spec violation!  */
@@ -1058,6 +1118,7 @@ static inline void cpu_probe_broadcom(struct cpuinfo_mips *c, unsigned int cpu)
                 break;
         }
         case PRID_IMP_BMIPS5000:
+        case PRID_IMP_BMIPS5200:
                 c->cputype = CPU_BMIPS5000;
                 __cpu_name[cpu] = "Broadcom BMIPS5000";
                 set_elf_platform(cpu, "bmips5000");
@@ -1288,6 +1349,8 @@ void cpu_probe(void)
                                     MIPS_CPU_ISA_M64R1 | MIPS_CPU_ISA_M64R2)) {
                         if (c->fpu_id & MIPS_FPIR_3D)
                                 c->ases |= MIPS_ASE_MIPS3D;
+                        if (c->fpu_id & MIPS_FPIR_FREP)
+                                c->options |= MIPS_CPU_FRE;
                 }
         }