| 96,14 → 96,13 |
|---|
| * Initialize ITLB and DTLB and switch to kernel |
| * trap table. |
| * |
| * The goal of this function is to disable MMU |
| * so that both TLBs can be purged and new |
| * kernel 4M locked entry can be installed. |
| * After TLB is initialized, MMU is enabled |
| * again. |
| * First, demap context 0 and install the |
| * global 4M locked kernel mapping. |
| * |
| * Switching MMU off imposes the requirement for |
| * the kernel to run in identity mapped environment. |
| * Second, prepare a temporary IMMU mapping in |
| * context 1, switch to it, demap context 0, |
| * install the global 4M locked kernel mapping |
| * in context 0 and switch back to context 0. |
| * |
| * @param base Base address that will be hardwired in both TLBs. |
| */ |
| 114,27 → 113,21 |
|---|
| frame_address_t fr; |
| page_address_t pg; |
| |
| /* |
| * Switch to the kernel trap table. |
| */ |
| trap_switch_trap_table(); |
| |
| fr.address = base; |
| pg.address = base; |
| |
| immu_disable(); |
| dmmu_disable(); |
| |
| /* |
| * Demap everything, especially OpenFirmware. |
| */ |
| itlb_demap(TLB_DEMAP_CONTEXT, TLB_DEMAP_NUCLEUS, 0); |
| dtlb_demap(TLB_DEMAP_CONTEXT, TLB_DEMAP_NUCLEUS, 0); |
| |
| /* |
| * We do identity mapping of 4M-page at 4M. |
| */ |
| tag.value = ASID_KERNEL; |
| tag.value = 0; |
| tag.context = 0; |
| tag.vpn = pg.vpn; |
| |
| itlb_tag_access_write(tag.value); |
| dtlb_tag_access_write(tag.value); |
| |
| data.value = 0; |
| data.v = true; |
| data.size = PAGESIZE_4M; |
| 141,25 → 134,43 |
|---|
| data.pfn = fr.pfn; |
| data.l = true; |
| data.cp = 1; |
| data.cv = 1; |
| data.cv = 0; |
| data.p = true; |
| data.w = true; |
| data.g = true; |
| |
| itlb_data_in_write(data.value); |
| /* |
| * Straightforwardly demap DMUU context 0, |
| * and replace it with the locked kernel mapping. |
| */ |
| dtlb_demap(TLB_DEMAP_CONTEXT, TLB_DEMAP_NUCLEUS, 0); |
| dtlb_tag_access_write(tag.value); |
| dtlb_data_in_write(data.value); |
| |
| /* |
| * Register window traps can occur before MMU is enabled again. |
| * This ensures that any such traps will be handled from |
| * kernel identity mapped trap handler. |
| * Install kernel code mapping in context 1 |
| * and switch to it. |
| */ |
| trap_switch_trap_table(); |
| tag.context = 1; |
| data.g = false; |
| itlb_tag_access_write(tag.value); |
| itlb_data_in_write(data.value); |
| mmu_primary_context_write(1); |
| |
| tlb_invalidate_all(); |
| |
| dmmu_enable(); |
| immu_enable(); |
| /* |
| * Demap old context 0. |
| */ |
| itlb_demap(TLB_DEMAP_CONTEXT, TLB_DEMAP_NUCLEUS, 0); |
| |
| /* |
| * Install the locked kernel mapping in context 0 |
| * and switch to it. |
| */ |
| tag.context = 0; |
| data.g = true; |
| itlb_tag_access_write(tag.value); |
| itlb_data_in_write(data.value); |
| mmu_primary_context_write(0); |
| } |
| |
| /** @} |