3 #include <video_defines.h>
6 #include <pci-bother.h>
8 #include "../net/net.h"
9 #include "vga-overlay.h"
12 #include "pagetable.h"
14 void set_cr0(unsigned int);
16 extern int entry_initialized;
17 extern int _bss, _bssend, _end;
21 register unsigned int _temp__; \
22 asm volatile("mov %%cr0, %0" : "=r" (_temp__)); \
27 #define set_cr3(value) \
29 register unsigned int _temp__ = (value); \
30 asm volatile("mov %0, %%cr3" : : "r" (_temp__)); \
32 #define CR0_PG 0x80000000
34 #define MAP_FLAGS (PTE_PRESENT | PTE_READ_WRITE)
36 void * pt_setup(int smbase) {
40 /* The page directory and page table live at SMBASE and SMBASE + 0x1000,
41 * respectively; clear them. */
42 int * pagedirectory = (int *) smbase;
43 int * pagetable = (int *) (smbase + 0x1000);
45 /* Clear out the page directory except for one entry pointing to the
46 * page table, and clear the page table entirely. */
48 pagedirectory[0] = (smbase + 0x1000) | PTE_PRESENT | PTE_READ_WRITE;
50 for (i = 1; i < 1024; i++)
56 for (i = 0; i < 1024; i++)
62 /* The page at 0x10000 - 0x10FFF points to the SMI entry point,
64 pagetable[16] = (0x8000 + smbase) | MAP_FLAGS;
66 /* 0x11000 to 0x1EFFF map to the rest of ASEG up to SMBASE + 0xF000;
67 * the page containing the saved state is not mappped to our code
70 for (i = 0; i < 8; i++)
72 pagetable[17 + i] = (i * 0x1000 + smbase) | MAP_FLAGS;
75 for (i = 0; i < 6; i++)
77 pagetable[25 + i] = (smbase + 0x9000 + i * 0x1000) | MAP_FLAGS;
81 /* Map 0xA8000 to itself. */
83 for (i = 0; i < 32; i++) {
84 pagetable[0xA0 + i] = (0xA0000 + i * 0x1000) | MAP_FLAGS;
87 /* Map 0x200000 to TSEG */
88 for (i = 0; i < 128; i++) {
89 pagetable[0x200 + i] = (0x1FF80000 + i * 0x1000) | MAP_FLAGS;
92 /* Map 0x300000 -> 0x200000, so we can copy our code out of
93 * RAM the first time around */
94 for (i = 0; i < 256; i++) {
95 /* pagetable[0x300 + i] = (0x200000 + i * 0x1000) | MAP_FLAGS;
97 pagetable[0x200 + i] = (0x200000 + i * 0x1000) | MAP_FLAGS;
101 return pagedirectory;
106 // unsigned char *bp;
109 char * pagedir = pt_setup(0xA0000);
111 set_cr3((int)pagedir);
115 set_cr0(get_cr0() | CR0_PG);
119 if (!entry_initialized) {
123 for (bp = (void *)0x200000; (void *)bp < (void *)&_bss; bp++)
124 *bp = *(bp + 0x100000);
126 for (bp = (void *)&_bss; (void *)bp < (void *)&_bssend; bp++)