diff options
Diffstat (limited to 'arch/arc/mm/cache.c')
| -rw-r--r-- | arch/arc/mm/cache.c | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/arch/arc/mm/cache.c b/arch/arc/mm/cache.c index 874913b3e826..7db283b46ebd 100644 --- a/arch/arc/mm/cache.c +++ b/arch/arc/mm/cache.c @@ -1123,6 +1123,13 @@ noinline void __init arc_ioc_setup(void) __dc_enable(); } +/* + * Cache related boot time checks/setups only needed on master CPU: + * - Geometry checks (kernel build and hardware agree: e.g. L1_CACHE_BYTES) + * Assume SMP only, so all cores will have same cache config. A check on + * one core suffices for all + * - IOC setup / dma callbacks only need to be done once + */ void __init arc_cache_init_master(void) { unsigned int __maybe_unused cpu = smp_processor_id(); @@ -1202,12 +1209,27 @@ void __ref arc_cache_init(void) printk(arc_cache_mumbojumbo(0, str, sizeof(str))); - /* - * Only master CPU needs to execute rest of function: - * - Assume SMP so all cores will have same cache config so - * any geomtry checks will be same for all - * - IOC setup / dma callbacks only need to be setup once - */ if (!cpu) arc_cache_init_master(); + + /* + * In PAE regime, TLB and cache maintenance ops take wider addresses + * And even if PAE is not enabled in kernel, the upper 32-bits still need + * to be zeroed to keep the ops sane. + * As an optimization for more common !PAE enabled case, zero them out + * once at init, rather than checking/setting to 0 for every runtime op + */ + if (is_isa_arcv2() && pae40_exist_but_not_enab()) { + + if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE)) + write_aux_reg(ARC_REG_IC_PTAG_HI, 0); + + if (IS_ENABLED(CONFIG_ARC_HAS_DCACHE)) + write_aux_reg(ARC_REG_DC_PTAG_HI, 0); + + if (l2_line_sz) { + write_aux_reg(ARC_REG_SLC_RGN_END1, 0); + write_aux_reg(ARC_REG_SLC_RGN_START1, 0); + } + } } |