diff options
Diffstat (limited to 'arch/mips/mm')
| -rw-r--r-- | arch/mips/mm/tlbex.c | 34 |
1 files changed, 26 insertions, 8 deletions
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c index 0615b62efd6..678e6339846 100644 --- a/arch/mips/mm/tlbex.c +++ b/arch/mips/mm/tlbex.c @@ -649,6 +649,14 @@ static void __cpuinit build_update_entries(u32 **p, unsigned int tmp, #endif } +/* + * For a 64-bit kernel, we are using the 64-bit XTLB refill exception + * because EXL == 0. If we wrap, we can also use the 32 instruction + * slots before the XTLB refill exception handler which belong to the + * unused TLB refill exception. + */ +#define MIPS64_REFILL_INSNS 32 + static void __cpuinit build_r4000_tlb_refill_handler(void) { u32 *p = tlb_handler; @@ -702,9 +710,10 @@ static void __cpuinit build_r4000_tlb_refill_handler(void) if ((p - tlb_handler) > 64) panic("TLB refill handler space exceeded"); #else - if (((p - tlb_handler) > 63) - || (((p - tlb_handler) > 61) - && uasm_insn_has_bdelay(relocs, tlb_handler + 29))) + if (((p - tlb_handler) > (MIPS64_REFILL_INSNS * 2) - 1) + || (((p - tlb_handler) > (MIPS64_REFILL_INSNS * 2) - 3) + && uasm_insn_has_bdelay(relocs, + tlb_handler + MIPS64_REFILL_INSNS - 3))) panic("TLB refill handler space exceeded"); #endif @@ -717,16 +726,24 @@ static void __cpuinit build_r4000_tlb_refill_handler(void) uasm_copy_handler(relocs, labels, tlb_handler, p, f); final_len = p - tlb_handler; #else /* CONFIG_64BIT */ - f = final_handler + 32; - if ((p - tlb_handler) <= 32) { + f = final_handler + MIPS64_REFILL_INSNS; + if ((p - tlb_handler) <= MIPS64_REFILL_INSNS) { /* Just copy the handler. */ uasm_copy_handler(relocs, labels, tlb_handler, p, f); final_len = p - tlb_handler; } else { - u32 *split = tlb_handler + 30; + /* + * Split two instructions before the end. One for the + * branch and one for the instruction in the delay + * slot. + */ + u32 *split = tlb_handler + MIPS64_REFILL_INSNS - 2; /* - * Find the split point. + * Find the split point. If the branch would fall in + * a delay slot, we must back up an additional + * instruction so that it is no longer in a delay + * slot. */ if (uasm_insn_has_bdelay(relocs, split - 1)) split--; @@ -749,7 +766,8 @@ static void __cpuinit build_r4000_tlb_refill_handler(void) /* Copy the rest of the handler. */ uasm_copy_handler(relocs, labels, split, p, final_handler); - final_len = (f - (final_handler + 32)) + (p - split); + final_len = (f - (final_handler + MIPS64_REFILL_INSNS)) + + (p - split); } #endif /* CONFIG_64BIT */ |