#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; } __attribute__ ((packed)); struct pg_table { struct pde pd[2048]; struct pde pdp[512]; } __attribute__ ((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 < 0) || (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; }