Load into SMRAM, not just video RAM.

[netwatch.git] / grubload / multiboot_c.c

diff --git a/grubload/multiboot_c.c b/grubload/multiboot_c.c
index 7c6a4fd11063d350ef055143ab222e1d2e85ca6a..ad421b4b713f6aa24a46c30e7a32c07b8e5a7c4f 100644 (file)
--- a/grubload/multiboot_c.c
+++ b/grubload/multiboot_c.c
@@ -1,6 +1,88 @@
-void c_start(unsigned int magic, void *wee)
+#include "console.h"
+#include <io.h>
+
+extern char _binary_realmode_bin_start[];
+extern int _binary_realmode_bin_size;
+
+struct mb_info

 {
 {

-       *(unsigned char *)0xB8000 = 'A';
-       while (1)
-               ;
+       unsigned long flags;
+       unsigned long mem_lower, mem_upper;
+       unsigned long boot_dev;
+       char *cmdline;
+       unsigned long mod_cnt;
+       struct mod_info *mods;
+};
+
+struct mod_info
+{
+       void *mod_start;
+       void *mod_end;
+       char *mod_string;
+       void *reserved;
+};
+
+void c_start(unsigned int magic, struct mb_info *wee)
+{
+       unsigned short *grubptr = 0x7CFE;
+       unsigned char smramc;
+       int i;
+       
+       void (*realmode)() = 0x4000;
+       
+       puts("Magic is: ");
+       puthex(magic);
+       puts("\nMultiboot header is: ");
+       puthex(wee);
+       puts("\n");
+       show_cursor();
+       
+       puts("Grubptr is: ");
+       puthex(*grubptr);
+       puts("\n");
+
+
+       for (i = 0; i < wee->mod_cnt; i++)
+       {
+               puts("Module:\n");
+               puts("  Start: "); puthex(wee->mods[i].mod_start); puts("\n");
+               puts("  Size: "); puthex(wee->mods[i].mod_end - wee->mods[i].mod_start); puts("\n");
+               puts("  Name: "); puts(wee->mods[i].mod_string); puts("\n");
+       }
+
+       if (wee->mod_cnt != 1)
+       {
+               puts("Expected exactly one module; cannot continue.\n");
+               while(1) asm("hlt");
+       }
+
+       puts("Current USB state is: "); puthex(pci_read16(0, 31, 2, 0xC0)); puts(" "); puthex(pci_read16(0, 31, 4, 0xC0)); puts("\n");
+       puts("Current SMI state is: "); puthex(inl(0x830)); puts("\n");
+       puts("Current SMRAMC state is: "); puthex(pci_read8(0, 0, 0, 0x70)); puts("\n");
+       
+       outl(0x830, inl(0x830) & ~0x2001);      /* turn off SMIs */
+       
+       /* Try really hard to shut up USB_LEGKEY. */
+       pci_write16(0, 31, 2, 0xC0, pci_read16(0, 31, 2, 0xC0));
+       pci_write16(0, 31, 2, 0xC0, 0);
+       pci_write16(0, 31, 4, 0xC0, pci_read16(0, 31, 4, 0xC0));
+       pci_write16(0, 31, 4, 0xC0, 0);
+       smramc = pci_read8(0, 0, 0, 0x70);
+       pci_write8(0, 0, 0, 0x70, (smramc & 0xF0) | 0x04);
+       load_elf(wee->mods[0].mod_start, wee->mods[0].mod_end - wee->mods[0].mod_start);
+       pci_write8(0, 0, 0, 0x70, smramc);
+       outb(0x830, inb(0x830) | 0x41); /* turn on the SMIs we want */
+       
+       puts("Waiting for a bit before returning to real mode...");
+       for (i=0; i<0x500000; i++)
+       {
+               if ((i % 0x100000) == 0)
+                       puts(".");
+               inb(0x80);
+       }
+       puts("\n");
+
+       puts("Now returning to real mode.\n");  
+       memcpy(0x4000, _binary_realmode_bin_start, (int)&_binary_realmode_bin_size);
+       realmode();     // goodbye!

 }
 }