/* * This file is part of the coreboot project. * * Copyright (C) 2005 Yinghai Lu * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <compiler.h> #include <console/console.h> #include <cpu/cpu.h> #include <cpu/x86/pae.h> #include <string.h> static void paging_off(void) { __asm__ __volatile__ ( /* Disable paging */ "movl %%cr0, %%eax\n\t" "andl $0x7FFFFFFF, %%eax\n\t" "movl %%eax, %%cr0\n\t" /* Disable pae */ "movl %%cr4, %%eax\n\t" "andl $0xFFFFFFDF, %%eax\n\t" "movl %%eax, %%cr4\n\t" : : : "eax" ); } static void paging_on(void *pdp) { __asm__ __volatile__( /* Load the page table address */ "movl %0, %%cr3\n\t" /* Enable pae */ "movl %%cr4, %%eax\n\t" "orl $0x00000020, %%eax\n\t" "movl %%eax, %%cr4\n\t" /* Enable paging */ "movl %%cr0, %%eax\n\t" "orl $0x80000000, %%eax\n\t" "movl %%eax, %%cr0\n\t" : : "r" (pdp) : "eax" ); } void *map_2M_page(unsigned long page) { struct pde { uint32_t addr_lo; uint32_t addr_hi; } __packed; struct pg_table { struct pde pd[2048]; struct pde pdp[512]; } __packed; static struct pg_table pgtbl[CONFIG_MAX_CPUS] __attribute__((aligned(4096))); static unsigned long mapped_window[CONFIG_MAX_CPUS]; unsigned long index; unsigned long window; void *result; int i; index = cpu_index(); if (index >= CONFIG_MAX_CPUS) return MAPPING_ERROR; window = page >> 10; if (window != mapped_window[index]) { paging_off(); if (window > 1) { struct pde *pd, *pdp; /* Point the page directory pointers at the page * directories */ memset(&pgtbl[index].pdp, 0, sizeof(pgtbl[index].pdp)); pd = pgtbl[index].pd; pdp = pgtbl[index].pdp; pdp[0].addr_lo = ((uint32_t)&pd[512*0])|1; pdp[1].addr_lo = ((uint32_t)&pd[512*1])|1; pdp[2].addr_lo = ((uint32_t)&pd[512*2])|1; pdp[3].addr_lo = ((uint32_t)&pd[512*3])|1; /* The first half of the page table is identity mapped */ for (i = 0; i < 1024; i++) { pd[i].addr_lo = ((i & 0x3ff) << 21) | 0xE3; pd[i].addr_hi = 0; } /* The second half of the page table holds the mapped * page */ for (i = 1024; i < 2048; i++) { pd[i].addr_lo = ((window & 1) << 31) | ((i & 0x3ff) << 21) | 0xE3; pd[i].addr_hi = (window >> 1); } paging_on(pdp); } mapped_window[index] = window; } if (window == 0) result = (void *)(page << 21); else result = (void *)(0x80000000 | ((page & 0x3ff) << 21)); return result; }