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#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;
}
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