Avoid suffering from wrong CS_SEGSEL syndrome.

[netwatch.git] / grubload / multiboot_c.c

diff --git a/grubload/multiboot_c.c b/grubload/multiboot_c.c
index c87b6755634dfab2c8b7b10c669f83ff33f6397d..5e30dde991d41efa29074137b1ceb837503d83fd 100644 (file)
--- a/grubload/multiboot_c.c
+++ b/grubload/multiboot_c.c
@@ -1,46 +1,99 @@
 #include "console.h"
 #include "console.h"

+#include "loader.h"
+#include <output.h>
+#include <minilib.h>
+#include <io.h>
+#include <smram.h>
+#include <multiboot.h>
+#include <smi.h>
+#include <pci.h>

 
 

-struct mb_info
+#define INFO_SIGNATURE 0x5754454E
+
+extern char _binary_realmode_bin_start[];
+extern int _binary_realmode_bin_size;
+
+struct info_section

 {
 {

-       unsigned long flags;
-       unsigned long mem_lower, mem_upper;
-       unsigned long boot_dev;
-       char *cmdline;
-       unsigned long mod_cnt;
-       struct mod_info *mods;
+       unsigned int signature;
+       void (*firstrun)();

 };
 
 };
 

-struct mod_info
+void panic(const char *msg)

 {
 {

-       void *mod_start;
-       void *mod_end;
-       char *mod_string;
-       void *reserved;
-};
+       outputf("PANIC: %s\nSystem halted\n", msg);
+       while(1) { __asm__("hlt"); }
+}

 
 

-void c_start(unsigned int magic, struct mb_info *wee)
+void c_start(unsigned int magic, struct mb_info *mbinfo)

 {
 {

-       unsigned short *grubptr = 0x7CFE;
+       struct mod_info *mods = mbinfo->mods;
+       smram_state_t old_smramc;
+       struct info_section * info;

        int i;
        
        int i;
        

-       puts("Magic is: ");
-       puthex(magic);
-       puts("\nMultiboot header is: ");
-       puthex(wee);
-       puts("\n");
+       void (*realmode)() = (void (*)()) 0x4000;
+       

        show_cursor();
        show_cursor();

+       outputf("NetWatch loader");

        
        

-       puts("Grubptr is: ");
-       puthex(*grubptr);
-       puts("\n");
+       if (magic != MULTIBOOT_LOADER_MAGIC)
+               panic("Bootloader was not multiboot compliant; cannot continue.");
+       
+       for (i = 0; i < mbinfo->mod_cnt; i++)
+       {
+               outputf("Module found:");
+               outputf("  Start: %08x", (unsigned long) mods[i].mod_start);
+               outputf("  Size: %08x", (unsigned long)mods[i].mod_end - (unsigned long)mods[i].mod_start);
+               outputf("  Name: %s", mods[i].mod_string);
+       }
+
+       if (mbinfo->mod_cnt != 1)
+               panic("Expected exactly one module; cannot continue.");
+       outputf("Current SMRAMC state is: %02x", pci_read8(0, 0, 0, 0x70));
+       outputf("Current USB state is: %04x %04x", pci_read16(0, 31, 2, 0xC0), pci_read16(0, 31, 4, 0xC0));
+       outputf("Current SMI state is: %08x", inl(0x830));

        
        

-       for (i = 0; i < wee->mod_cnt; i++)
+       smi_disable();
+       
+       /* 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);
+/*     
+       pci_bus_enum();
+*/
+       /* Open the SMRAM aperture and load our ELF. */
+       old_smramc = smram_save_state();
+
+       if (smram_aseg_set_state(SMRAM_ASEG_OPEN) != 0)
+               panic("Opening SMRAM failed; cannot load ELF.");
+
+       load_elf(mods[0].mod_start, (unsigned long)mods[0].mod_end - (unsigned long)mods[0].mod_start);
+
+       info = (struct info_section *)0x10000;
+       if (info->signature != INFO_SIGNATURE)

        {
        {

-               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");
+               smram_restore_state(old_smramc);                /* Restore so that video ram is touchable again. */
+               panic("Info section signature mismatch.");

        }
        }

-       while (1)
-               ;
+
+       info->firstrun();
+       smram_restore_state(old_smramc);
+       
+       outputf("New SMRAMC state is: %02x", pci_read8(0, 0, 0, 0x70));
+
+       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");
+
+       outputf("Now returning to real mode.");
+       memcpy((void *)0x4000, _binary_realmode_bin_start, (int)&_binary_realmode_bin_size);
+       realmode();     // goodbye!

 }
 }