/* $NetBSD: pmap_bootstrap.c,v 1.65 2026/03/29 20:42:51 thorpej Exp $ */ /* * Copyright (c) 1991, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed to Berkeley by * the Systems Programming Group of the University of Utah Computer * Science Department. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)pmap_bootstrap.c 8.1 (Berkeley) 6/10/93 */ #include __KERNEL_RCSID(0, "$NetBSD: pmap_bootstrap.c,v 1.65 2026/03/29 20:42:51 thorpej Exp $"); #include "opt_m68k_arch.h" #include #include #include #include #include #include #include #define RELOC(v, t) *((t*)((uintptr_t)&(v) + firstpa)) extern char *etext; extern vaddr_t kernel_reloc_offset; /* * Special purpose kernel virtual addresses, used for mapping * physical pages for a variety of temporary or permanent purposes: * * CADDR1, CADDR2: pmap zero/copy operations * vmmap: /dev/mem, crash dumps, parity error checking * msgbufaddr: kernel message buffer */ void *CADDR1, *CADDR2; char *vmmap; void *msgbufaddr; paddr_t pmap_bootstrap1(paddr_t, paddr_t); /* * Bootstrap the VM system. * * Called with MMU off so we must relocate all global references by `firstpa' * (don't call any functions here!) `nextpa' is the first available physical * memory address. Returns an updated first PA reflecting the memory we * have allocated. MMU is still off when we return. * * XXX assumes sizeof(u_int) == sizeof(pt_entry_t) * XXX a PIC compiler would make this much easier. */ paddr_t __attribute__((no_instrument_function)) pmap_bootstrap1(paddr_t nextpa, paddr_t firstpa) { paddr_t lwp0upa, kstpa, kptmpa, kptpa; u_int nptpages, kstsize; st_entry_t protoste, *ste, *este; pt_entry_t protopte, *pte, *epte; u_int iiomappages; #if defined(M68040) || defined(M68060) int i; u_int stfree = 0; /* XXX: gcc -Wuninitialized */ #endif nextpa = m68k_round_page(nextpa); /* * Calculate important physical addresses: * * lwp0upa lwp0 u-area UPAGES pages * * kstpa kernel segment table 1 page (!040) * N pages (040) * * kptmpa kernel PT map 1 page * * kptpa statically allocated * kernel PT pages Sysptsize+ pages * * [ Sysptsize is the number of pages of PT, and iiomappages is the * number of PTEs, hence we need to round the total to a page * boundary with IO maps at the end. ] * * The KVA corresponding to any of these PAs is: * (PA - firstpa + KERNBASE). */ RELOC(kernel_reloc_offset, vaddr_t) = firstpa; u_int intio_endpa = RELOC(intiobase_phys, u_int) + RELOC(intiosize, u_int); iiomappages = m68k_btop(intio_endpa - RELOC(intiobase_phys, u_int)); lwp0upa = nextpa; nextpa += USPACE; #if defined(M68040) || defined(M68060) if (RELOC(mmutype, int) == MMU_68040) kstsize = MAXKL2SIZE / (NPTEPG/SG4_LEV2SIZE); else #endif kstsize = 1; kstpa = nextpa; nextpa += kstsize * PAGE_SIZE; kptmpa = nextpa; nextpa += PAGE_SIZE; kptpa = nextpa; nptpages = RELOC(Sysptsize, int) + howmany(RELOC(physmem, psize_t), NPTEPG) + (iiomappages + NPTEPG - 1) / NPTEPG; nextpa += nptpages * PAGE_SIZE; /* * Clear all PTEs to zero */ for (pte = (pt_entry_t *)kstpa; pte < (pt_entry_t *)nextpa; pte++) *pte = 0; /* * Initialize segment table and kernel page table map. * * On 68030s and earlier MMUs the two are identical except for * the valid bits so both are initialized with essentially the * same values. On the 68040, which has a mandatory 3-level * structure, the segment table holds the level 1 table and part * (or all) of the level 2 table and hence is considerably * different. Here the first level consists of 128 descriptors * (512 bytes) each mapping 32mb of address space. Each of these * points to blocks of 128 second level descriptors (512 bytes) * each mapping 256kb. Note that there may be additional "segment * table" pages depending on how large MAXKL2SIZE is. * * Portions of the last segment of KVA space (0xFFC00000 - * 0xFFFFFFFF) are mapped for the kernel page tables. * * XXX cramming two levels of mapping into the single "segment" * table on the 68040 is intended as a temporary hack to get things * working. The 224mb of address space that this allows will most * likely be insufficient in the future (at least for the kernel). */ #if defined(M68040) || defined(M68060) if (RELOC(mmutype, int) == MMU_68040) { int nl1desc, nl2desc; /* * First invalidate the entire "segment table" pages * (levels 1 and 2 have the same "invalid" value). */ ste = (st_entry_t *)kstpa; este = &ste[kstsize * NPTEPG]; while (ste < este) *ste++ = SG_NV; /* * Initialize level 2 descriptors (which immediately * follow the level 1 table). We need: * NPTEPG / SG4_LEV3SIZE * level 2 descriptors to map each of the nptpages * pages of PTEs. Note that we set the "used" bit * now to save the HW the expense of doing it. */ nl2desc = nptpages * (NPTEPG / SG4_LEV3SIZE); ste = (st_entry_t *)kstpa; ste = &ste[SG4_LEV1SIZE]; este = &ste[nl2desc]; protoste = kptpa | SG_U | SG_RW | SG_V; while (ste < este) { *ste++ = protoste; protoste += (SG4_LEV3SIZE * sizeof(st_entry_t)); } /* * Initialize level 1 descriptors. We need: * howmany(nl2desc, SG4_LEV2SIZE) * level 1 descriptors to map the `nl2desc' level 2's. */ nl1desc = howmany(nl2desc, SG4_LEV2SIZE); ste = (st_entry_t *)kstpa; este = &ste[nl1desc]; protoste = (paddr_t)&ste[SG4_LEV1SIZE] | SG_U | SG_RW | SG_V; while (ste < este) { *ste++ = protoste; protoste += (SG4_LEV2SIZE * sizeof(st_entry_t)); } /* * Initialize the final level 1 descriptor to map the next * block of level 2 descriptors for Sysptmap. */ ste = (st_entry_t *)kstpa; ste = &ste[SG4_LEV1SIZE - 1]; *ste = protoste; /* * Now initialize the final portion of that block of * descriptors to map Sysmap. */ i = SG4_LEV1SIZE + (nl1desc * SG4_LEV2SIZE); ste = (st_entry_t *)kstpa; ste = &ste[i + SG4_LEV2SIZE - (NPTEPG / SG4_LEV3SIZE)]; este = &ste[NPTEPG / SG4_LEV3SIZE]; protoste = kptmpa | SG_U | SG_RW | SG_V; while (ste < este) { *ste++ = protoste; protoste += (SG4_LEV3SIZE * sizeof(st_entry_t)); } /* * Calculate the free level 2 descriptor mask * noting that we have used: * 0: level 1 table * 1 to nl1desc: map page tables * nl1desc + 1: maps kptmpa and last-page page table */ /* mark an entry for level 1 table */ stfree = ~l2tobm(0); /* mark entries for map page tables */ for (i = 1; i <= nl1desc; i++) stfree &= ~l2tobm(i); /* mark an entry for kptmpa and lkptpa */ stfree &= ~l2tobm(i); /* mark entries not available */ for (i = MAXKL2SIZE; i < sizeof(stfree) * NBBY; i++) stfree &= ~l2tobm(i); /* * Initialize Sysptmap */ pte = (pt_entry_t *)kptmpa; epte = &pte[nptpages]; protopte = kptpa | PG_RW | PG_CI | PG_U | PG_V; while (pte < epte) { *pte++ = protopte; protopte += PAGE_SIZE; } /* * Invalidate all remaining entries. */ epte = (pt_entry_t *)kptmpa; epte = &epte[TIB_SIZE]; while (pte < epte) { *pte++ = PG_NV; } /* * Initialize the last one to point to Sysptmap. */ pte = (pt_entry_t *)kptmpa; pte = &pte[SYSMAP_VA >> SEGSHIFT]; *pte = kptmpa | PG_RW | PG_CI | PG_V; } else #endif /* M68040 || M68060 */ { /* * Map the page table pages in both the HW segment table * and the software Sysptmap. */ ste = (st_entry_t *)kstpa; pte = (pt_entry_t *)kptmpa; epte = &pte[nptpages]; protoste = kptpa | SG_RW | SG_V; protopte = kptpa | PG_RW | PG_CI | PG_V; while (pte < epte) { *ste++ = protoste; *pte++ = protopte; protoste += PAGE_SIZE; protopte += PAGE_SIZE; } /* * Invalidate all remaining entries in both. */ este = (st_entry_t *)kstpa; este = &este[TIA_SIZE]; while (ste < este) *ste++ = SG_NV; epte = (pt_entry_t *)kptmpa; epte = &epte[TIB_SIZE]; while (pte < epte) *pte++ = PG_NV; /* * Initialize the last one to point to Sysptmap. */ ste = (st_entry_t *)kstpa; ste = &ste[SYSMAP_VA >> SEGSHIFT]; pte = (pt_entry_t *)kptmpa; pte = &pte[SYSMAP_VA >> SEGSHIFT]; *ste = kptmpa | SG_RW | SG_V; *pte = kptmpa | PG_RW | PG_CI | PG_V; } /* * Initialize kernel page table. * Start by invalidating the `nptpages' that we have allocated. */ pte = (pt_entry_t *)kptpa; epte = &pte[nptpages * NPTEPG]; while (pte < epte) *pte++ = PG_NV; /* * Validate PTEs for kernel text (RO). */ pte = (pt_entry_t *)kptpa; pte = &pte[m68k_btop(KERNBASE)]; epte = &pte[m68k_btop(m68k_trunc_page(&etext))]; protopte = firstpa | PG_RO | PG_U | PG_V; while (pte < epte) { *pte++ = protopte; protopte += PAGE_SIZE; } /* * Validate PTEs for kernel data/bss, dynamic data allocated * by us so far (kstpa - firstpa bytes), and pages for lwp0 * u-area and page table allocated below (RW). */ epte = (pt_entry_t *)kptpa; epte = &epte[m68k_btop(kstpa - firstpa)]; protopte = (protopte & ~PG_PROT) | PG_RW; /* * Enable copy-back caching of data pages */ if (RELOC(mmutype, int) == MMU_68040) protopte |= PG_CCB; while (pte < epte) { *pte++ = protopte; protopte += PAGE_SIZE; } /* * Map the kernel segment table cache invalidated for 68040/68060. * (for the 68040 not strictly necessary, but recommended by Motorola; * for the 68060 mandatory) */ epte = (pt_entry_t *)kptpa; epte = &epte[m68k_btop(nextpa - firstpa)]; protopte = (protopte & ~PG_PROT) | PG_RW; if (RELOC(mmutype, int) == MMU_68040) { protopte &= ~PG_CMASK; protopte |= PG_CI; } while (pte < epte) { *pte++ = protopte; protopte += PAGE_SIZE; } /* * Finally, validate the internal IO space PTEs (RW+CI). */ #define PTE2VA(pte) m68k_ptob(pte - ((pt_entry_t *)kptpa)) protopte = RELOC(intiobase_phys, u_int) | PG_RW | PG_CI | PG_U | PG_V; epte = &pte[iiomappages]; RELOC(intiobase, uint8_t *) = (uint8_t *)PTE2VA(pte); while (pte < epte) { *pte++ = protopte; protopte += PAGE_SIZE; } RELOC(virtual_avail, vaddr_t) = PTE2VA(pte); /* * Calculate important exported kernel addresses and related values. */ /* * Sysseg: base of kernel segment table */ RELOC(Sysseg, st_entry_t *) = (st_entry_t *)(kstpa - firstpa); RELOC(Sysseg_pa, paddr_t) = kstpa; #if defined(M68040) || defined(M68060) if (RELOC(mmutype, int) == MMU_68040) RELOC(protostfree, u_int) = stfree; #endif /* * Sysptmap: base of kernel page table map */ RELOC(Sysptmap, pt_entry_t *) = (pt_entry_t *)(kptmpa - firstpa); /* * Sysmap: kernel page table (as mapped through Sysptmap) * Allocated at the end of KVA space. */ RELOC(Sysmap, pt_entry_t *) = (pt_entry_t *)SYSMAP_VA; /* * Remember the u-area address so it can be loaded in the lwp0 * via uvm_lwp_setuarea() later in pmap_bootstrap2(). */ RELOC(lwp0uarea, vaddr_t) = lwp0upa - firstpa; RELOC(virtual_end, vaddr_t) = VM_MAX_KERNEL_ADDRESS; /* * Allocate some fixed, special purpose kernel virtual addresses */ { vaddr_t va = RELOC(virtual_avail, vaddr_t); RELOC(CADDR1, void *) = (void *)va; va += PAGE_SIZE; RELOC(CADDR2, void *) = (void *)va; va += PAGE_SIZE; RELOC(vmmap, void *) = (void *)va; va += PAGE_SIZE; RELOC(msgbufaddr, void *) = (void *)va; va += m68k_round_page(MSGBUFSIZE); RELOC(virtual_avail, vaddr_t) = va; } return nextpa; }