diff options
Diffstat (limited to 'arch/mips/mti-sead3/sead3-init.c')
| -rw-r--r-- | arch/mips/mti-sead3/sead3-init.c | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/arch/mips/mti-sead3/sead3-init.c b/arch/mips/mti-sead3/sead3-init.c index 562dccf56ee..bfbd17b120a 100644 --- a/arch/mips/mti-sead3/sead3-init.c +++ b/arch/mips/mti-sead3/sead3-init.c @@ -65,7 +65,41 @@ static void __init mips_nmi_setup(void) base = cpu_has_veic ? (void *)(CAC_BASE + 0xa80) : (void *)(CAC_BASE + 0x380); +#ifdef CONFIG_CPU_MICROMIPS + /* + * Decrement the exception vector address by one for microMIPS. + */ + memcpy(base, (&except_vec_nmi - 1), 0x80); + + /* + * This is a hack. We do not know if the boot loader was built with + * microMIPS instructions or not. If it was not, the NMI exception + * code at 0x80000a80 will be taken in MIPS32 mode. The hand coded + * assembly below forces us into microMIPS mode if we are a pure + * microMIPS kernel. The assembly instructions are: + * + * 3C1A8000 lui k0,0x8000 + * 375A0381 ori k0,k0,0x381 + * 03400008 jr k0 + * 00000000 nop + * + * The mode switch occurs by jumping to the unaligned exception + * vector address at 0x80000381 which would have been 0x80000380 + * in MIPS32 mode. The jump to the unaligned address transitions + * us into microMIPS mode. + */ + if (!cpu_has_veic) { + void *base2 = (void *)(CAC_BASE + 0xa80); + *((unsigned int *)base2) = 0x3c1a8000; + *((unsigned int *)base2 + 1) = 0x375a0381; + *((unsigned int *)base2 + 2) = 0x03400008; + *((unsigned int *)base2 + 3) = 0x00000000; + flush_icache_range((unsigned long)base2, + (unsigned long)base2 + 0x10); + } +#else memcpy(base, &except_vec_nmi, 0x80); +#endif flush_icache_range((unsigned long)base, (unsigned long)base + 0x80); } @@ -76,7 +110,21 @@ static void __init mips_ejtag_setup(void) base = cpu_has_veic ? (void *)(CAC_BASE + 0xa00) : (void *)(CAC_BASE + 0x300); +#ifdef CONFIG_CPU_MICROMIPS + /* Deja vu... */ + memcpy(base, (&except_vec_ejtag_debug - 1), 0x80); + if (!cpu_has_veic) { + void *base2 = (void *)(CAC_BASE + 0xa00); + *((unsigned int *)base2) = 0x3c1a8000; + *((unsigned int *)base2 + 1) = 0x375a0301; + *((unsigned int *)base2 + 2) = 0x03400008; + *((unsigned int *)base2 + 3) = 0x00000000; + flush_icache_range((unsigned long)base2, + (unsigned long)base2 + 0x10); + } +#else memcpy(base, &except_vec_ejtag_debug, 0x80); +#endif flush_icache_range((unsigned long)base, (unsigned long)base + 0x80); } |