Joshua Wise's Git repositories - netwatch.git/blame_incremental

... / ...

Commit	Line	Data
	1	/* multiboot_c.c
	2	* Main program for starting SMM code
	3	* NetWatch multiboot loader
	4	*
	5	* Copyright (c) 2008 Jacob Potter and Joshua Wise. All rights reserved.
	6	* This program is free software; you can redistribute and/or modify it under
	7	* the terms found in the file LICENSE in the root of this source tree.
	8	*
	9	*/
	10
	11	#include "console.h"
	12	#include "loader.h"
	13	#include <output.h>
	14	#include <minilib.h>
	15	#include <io.h>
	16	#include <smram.h>
	17	#include <multiboot.h>
	18	#include <smi.h>
	19	#include <pci.h>
	20
	21	#define INFO_SIGNATURE 0x5754454E
	22
	23	extern char _binary_realmode_bin_start[];
	24	extern int _binary_realmode_bin_size;
	25
	26	struct info_section
	27	{
	28	unsigned int signature;
	29	void (*firstrun)();
	30	};
	31
	32	void panic(const char *msg)
	33	{
	34	outputf("PANIC: %s\nSystem halted\n", msg);
	35	while(1) { __asm__("hlt"); }
	36	}
	37
	38	void c_start(unsigned int magic, struct mb_info *mbinfo)
	39	{
	40	struct mod_info *mods = mbinfo->mods;
	41	smram_state_t old_smramc;
	42	struct info_section * info;
	43	int i;
	44
	45	void (realmode)() = (void ()()) 0x4000;
	46
	47	show_cursor();
	48	outputf("NetWatch loader");
	49
	50	if (magic != MULTIBOOT_LOADER_MAGIC)
	51	panic("Bootloader was not multiboot compliant; cannot continue.");
	52
	53	for (i = 0; i < mbinfo->mod_cnt; i++)
	54	{
	55	outputf("Module found:");
	56	outputf(" Start: %08x", (unsigned long) mods[i].mod_start);
	57	outputf(" Size: %08x", (unsigned long)mods[i].mod_end - (unsigned long)mods[i].mod_start);
	58	outputf(" Name: %s", mods[i].mod_string);
	59	}
	60
	61	if (mbinfo->mod_cnt != 1)
	62	panic("Expected exactly one module; cannot continue.");
	63	outputf("Current SMRAMC state is: %02x", pci_read8(0, 0, 0, 0x70));
	64	outputf("Current USB state is: %04x %04x", pci_read16(0, 31, 2, 0xC0), pci_read16(0, 31, 4, 0xC0));
	65	outputf("Current SMI state is: %08x", inl(0x830));
	66
	67	smi_disable();
	68
	69	/* Try really hard to shut up USB_LEGKEY. */
	70	pci_write16(0, 31, 2, 0xC0, pci_read16(0, 31, 2, 0xC0));
	71	pci_write16(0, 31, 2, 0xC0, 0);
	72	pci_write16(0, 31, 4, 0xC0, pci_read16(0, 31, 4, 0xC0));
	73	pci_write16(0, 31, 4, 0xC0, 0);
	74	/*
	75	pci_bus_enum();
	76	*/
	77	/* Open the SMRAM aperture and load our ELF. */
	78	old_smramc = smram_save_state();
	79
	80	if (smram_aseg_set_state(SMRAM_ASEG_OPEN) != 0)
	81	panic("Opening SMRAM failed; cannot load ELF.");
	82
	83	load_elf(mods[0].mod_start, (unsigned long)mods[0].mod_end - (unsigned long)mods[0].mod_start);
	84
	85	info = (struct info_section *)0x10000;
	86	if (info->signature != INFO_SIGNATURE)
	87	{
	88	smram_restore_state(old_smramc); /* Restore so that video ram is touchable again. */
	89	panic("Info section signature mismatch.");
	90	}
	91
	92	info->firstrun();
	93	smram_restore_state(old_smramc);
	94
	95	outputf("New SMRAMC state is: %02x", pci_read8(0, 0, 0, 0x70));
	96
	97	puts("Waiting for a bit before returning to real mode...");
	98	for (i=0; i<0x500000; i++)
	99	{
	100	if ((i % 0x100000) == 0)
	101	puts(".");
	102	inb(0x80);
	103	}
	104	puts("\n");
	105
	106	outputf("Now returning to real mode.");
	107	memcpy((void *)0x4000, _binary_realmode_bin_start, (int)&_binary_realmode_bin_size);
	108	realmode(); // goodbye!
	109	}