bios32.c

GNU Mach 微内核源代码, 基于美国卡内基美隆大学的 Mach 研究项目

	if (dev->vendor == vendor && dev->device == device_id) {
	    if (curr == index) {
		*devfn = dev->devfn;
		*bus = dev->bus->number;
		return PCIBIOS_SUCCESSFUL;
	    }
	    ++curr;
	}
    }
    return PCIBIOS_DEVICE_NOT_FOUND;
}


/*
 * Given the class, find the n'th instance of that device
 * in the system.
 */
static int pci_direct_find_class (unsigned int class_code, unsigned short index,
			  unsigned char *bus, unsigned char *devfn)
{
    unsigned int curr = 0;
    struct pci_dev *dev;

    for (dev = pci_devices; dev; dev = dev->next) {
	if (dev->class == class_code) {
	    if (curr == index) {
		*devfn = dev->devfn;
		*bus = dev->bus->number;
		return PCIBIOS_SUCCESSFUL;
	    }
	    ++curr;
	}
    }
    return PCIBIOS_DEVICE_NOT_FOUND;
}

/*
 * Functions for accessing PCI configuration space with type 1 accesses
 */
#define CONFIG_CMD(bus, device_fn, where)   (0x80000000 | (bus << 16) | (device_fn << 8) | (where & ~3))

static int pci_conf1_read_config_byte(unsigned char bus, unsigned char device_fn,
			       unsigned char where, unsigned char *value)
{
    unsigned long flags;

    save_flags(flags); cli();
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    *value = inb(0xCFC + (where&3));
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

static int pci_conf1_read_config_word (unsigned char bus,
    unsigned char device_fn, unsigned char where, unsigned short *value)
{
    unsigned long flags;

    if (where&1) return PCIBIOS_BAD_REGISTER_NUMBER;
    save_flags(flags); cli();
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);    
    *value = inw(0xCFC + (where&2));
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;    
}

static int pci_conf1_read_config_dword (unsigned char bus, unsigned char device_fn, 
				 unsigned char where, unsigned int *value)
{
    unsigned long flags;

    if (where&3) return PCIBIOS_BAD_REGISTER_NUMBER;
    save_flags(flags); cli();
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    *value = inl(0xCFC);
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;    
}

static int pci_conf1_write_config_byte (unsigned char bus, unsigned char device_fn, 
				 unsigned char where, unsigned char value)
{
    unsigned long flags;

    save_flags(flags); cli();
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);    
    outb(value, 0xCFC + (where&3));
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

static int pci_conf1_write_config_word (unsigned char bus, unsigned char device_fn, 
				 unsigned char where, unsigned short value)
{
    unsigned long flags;

    if (where&1) return PCIBIOS_BAD_REGISTER_NUMBER;
    save_flags(flags); cli();
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    outw(value, 0xCFC + (where&2));
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

static int pci_conf1_write_config_dword (unsigned char bus, unsigned char device_fn, 
				  unsigned char where, unsigned int value)
{
    unsigned long flags;

    if (where&3) return PCIBIOS_BAD_REGISTER_NUMBER;
    save_flags(flags); cli();
    outl(CONFIG_CMD(bus,device_fn,where), 0xCF8);
    outl(value, 0xCFC);
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

#undef CONFIG_CMD

/*
 * functiontable for type 1
 */
static struct pci_access pci_direct_conf1 = {
      pci_direct_find_device,
      pci_direct_find_class,
      pci_conf1_read_config_byte,
      pci_conf1_read_config_word,
      pci_conf1_read_config_dword,
      pci_conf1_write_config_byte,
      pci_conf1_write_config_word,
      pci_conf1_write_config_dword
};

/*
 * Functions for accessing PCI configuration space with type 2 accesses
 */
#define IOADDR(devfn, where)   ((0xC000 | ((devfn & 0x78) << 5)) + where)
#define FUNC(devfn)            (((devfn & 7) << 1) | 0xf0)

static int pci_conf2_read_config_byte(unsigned char bus, unsigned char device_fn, 
			       unsigned char where, unsigned char *value)
{
    unsigned long flags;

    if (device_fn & 0x80)
	return PCIBIOS_DEVICE_NOT_FOUND;
    save_flags(flags); cli();
    outb (FUNC(device_fn), 0xCF8);
    outb (bus, 0xCFA);
    *value = inb(IOADDR(device_fn,where));
    outb (0, 0xCF8);
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

static int pci_conf2_read_config_word (unsigned char bus, unsigned char device_fn, 
				unsigned char where, unsigned short *value)
{
    unsigned long flags;

    if (device_fn & 0x80)
	return PCIBIOS_DEVICE_NOT_FOUND;
    save_flags(flags); cli();
    outb (FUNC(device_fn), 0xCF8);
    outb (bus, 0xCFA);
    *value = inw(IOADDR(device_fn,where));
    outb (0, 0xCF8);
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

static int pci_conf2_read_config_dword (unsigned char bus, unsigned char device_fn, 
				 unsigned char where, unsigned int *value)
{
    unsigned long flags;

    if (device_fn & 0x80)
	return PCIBIOS_DEVICE_NOT_FOUND;
    save_flags(flags); cli();
    outb (FUNC(device_fn), 0xCF8);
    outb (bus, 0xCFA);
    *value = inl (IOADDR(device_fn,where));    
    outb (0, 0xCF8);    
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

static int pci_conf2_write_config_byte (unsigned char bus, unsigned char device_fn, 
				 unsigned char where, unsigned char value)
{
    unsigned long flags;

    save_flags(flags); cli();
    outb (FUNC(device_fn), 0xCF8);
    outb (bus, 0xCFA);
    outb (value, IOADDR(device_fn,where));
    outb (0, 0xCF8);    
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

static int pci_conf2_write_config_word (unsigned char bus, unsigned char device_fn, 
				 unsigned char where, unsigned short value)
{
    unsigned long flags;

    save_flags(flags); cli();
    outb (FUNC(device_fn), 0xCF8);
    outb (bus, 0xCFA);
    outw (value, IOADDR(device_fn,where));
    outb (0, 0xCF8);    
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

static int pci_conf2_write_config_dword (unsigned char bus, unsigned char device_fn, 
				  unsigned char where, unsigned int value)
{
    unsigned long flags;

    save_flags(flags); cli();
    outb (FUNC(device_fn), 0xCF8);
    outb (bus, 0xCFA);
    outl (value, IOADDR(device_fn,where));    
    outb (0, 0xCF8);    
    restore_flags(flags);
    return PCIBIOS_SUCCESSFUL;
}

#undef IOADDR
#undef FUNC

/*
 * functiontable for type 2
 */
static struct pci_access pci_direct_conf2 = {
      pci_direct_find_device,
      pci_direct_find_class,
      pci_conf2_read_config_byte,
      pci_conf2_read_config_word,
      pci_conf2_read_config_dword,
      pci_conf2_write_config_byte,
      pci_conf2_write_config_word,
      pci_conf2_write_config_dword
};


static struct pci_access *check_direct_pci(void)
{
    unsigned int tmp;
    unsigned long flags;

    save_flags(flags); cli();

    /*
     * check if configuration type 1 works
     */
    outb (0x01, 0xCFB);
    tmp = inl (0xCF8);
    outl (0x80000000, 0xCF8);
    if (inl (0xCF8) == 0x80000000) {
	outl (tmp, 0xCF8);
	restore_flags(flags);
	printk("pcibios_init: Using configuration type 1\n");
	return &pci_direct_conf1;
    }
    outl (tmp, 0xCF8);

    /*
     * check if configuration type 2 works
     */
    outb (0x00, 0xCFB);
    outb (0x00, 0xCF8);
    outb (0x00, 0xCFA);
    if (inb (0xCF8) == 0x00 && inb (0xCFB) == 0x00) {
	restore_flags(flags);
	printk("pcibios_init: Using configuration type 2\n");
	return &pci_direct_conf2;
    }
    restore_flags(flags);
    printk("pcibios_init: Not supported chipset for direct PCI access !\n");
    return NULL;
}


/*
 * access defined pcibios functions via
 * the function table
 */

int pcibios_present(void)
{
	return access_pci ? 1 : 0;
}

int pcibios_find_class (unsigned int class_code, unsigned short index,
	unsigned char *bus, unsigned char *device_fn)
{
   if (access_pci && access_pci->find_class)
      return access_pci->find_class(class_code, index, bus, device_fn);
    
    return PCIBIOS_FUNC_NOT_SUPPORTED;
}

int pcibios_find_device (unsigned short vendor, unsigned short device_id,
	unsigned short index, unsigned char *bus, unsigned char *device_fn)
{
    if (access_pci && access_pci->find_device)
      return access_pci->find_device(vendor, device_id, index, bus, device_fn);
    
    return PCIBIOS_FUNC_NOT_SUPPORTED;
}

int pcibios_read_config_byte (unsigned char bus,
	unsigned char device_fn, unsigned char where, unsigned char *value)
{
    if (access_pci && access_pci->read_config_byte)
      return access_pci->read_config_byte(bus, device_fn, where, value);
    
    return PCIBIOS_FUNC_NOT_SUPPORTED;
}

int pcibios_read_config_word (unsigned char bus,
	unsigned char device_fn, unsigned char where, unsigned short *value)
{
    if (access_pci && access_pci->read_config_word)
      return access_pci->read_config_word(bus, device_fn, where, value);
    
    return PCIBIOS_FUNC_NOT_SUPPORTED;
}

int pcibios_read_config_dword (unsigned char bus,
	unsigned char device_fn, unsigned char where, unsigned int *value)
{
    if (access_pci && access_pci->read_config_dword)
      return access_pci->read_config_dword(bus, device_fn, where, value);
    
    return PCIBIOS_FUNC_NOT_SUPPORTED;
}

int pcibios_write_config_byte (unsigned char bus,
	unsigned char device_fn, unsigned char where, unsigned char value)
{
    if (access_pci && access_pci->write_config_byte)
      return access_pci->write_config_byte(bus, device_fn, where, value);
    
    return PCIBIOS_FUNC_NOT_SUPPORTED;
}

int pcibios_write_config_word (unsigned char bus,
	unsigned char device_fn, unsigned char where, unsigned short value)
{
    if (access_pci && access_pci->write_config_word)
      return access_pci->write_config_word(bus, device_fn, where, value);
    
    return PCIBIOS_FUNC_NOT_SUPPORTED;    
}

int pcibios_write_config_dword (unsigned char bus,
	unsigned char device_fn, unsigned char where, unsigned int value)
{
    if (access_pci && access_pci->write_config_dword)
      return access_pci->write_config_dword(bus, device_fn, where, value);
    
    return PCIBIOS_FUNC_NOT_SUPPORTED;
}

const char *pcibios_strerror (int error)
{
	static char buf[80];

	switch (error) {
		case PCIBIOS_SUCCESSFUL:
			return "SUCCESSFUL";

		case PCIBIOS_FUNC_NOT_SUPPORTED:
			return "FUNC_NOT_SUPPORTED";

		case PCIBIOS_BAD_VENDOR_ID:
			return "SUCCESSFUL";

		case PCIBIOS_DEVICE_NOT_FOUND:
			return "DEVICE_NOT_FOUND";

		case PCIBIOS_BAD_REGISTER_NUMBER:
			return "BAD_REGISTER_NUMBER";

                case PCIBIOS_SET_FAILED:          
			return "SET_FAILED";

                case PCIBIOS_BUFFER_TOO_SMALL:    
			return "BUFFER_TOO_SMALL";

		default:
			sprintf (buf, "UNKNOWN RETURN 0x%x", error);
			return buf;
	}
}


unsigned long pcibios_fixup(unsigned long mem_start, unsigned long mem_end)
{
    return mem_start;
}

#endif

unsigned long pcibios_init(unsigned long memory_start, unsigned long memory_end)
{
#ifdef CONFIG_PCI
	union bios32 *check;
	unsigned char sum;
	int i, length;

	/*
	 * Follow the standard procedure for locating the BIOS32 Service
	 * directory by scanning the permissible address range from
	 * 0xe0000 through 0xfffff for a valid BIOS32 structure.
	 *
	 */

	for (check = (union bios32 *) 0xe0000;
	     check <= (union bios32 *) 0xffff0;
	     ++check) {
		if (check->fields.signature != BIOS32_SIGNATURE)
			continue;
		length = check->fields.length * 16;
		if (!length)
			continue;
		sum = 0;
		for (i = 0; i < length ; ++i)
			sum += check->chars[i];
		if (sum != 0)
			continue;
		if (check->fields.revision != 0) {
			printk("pcibios_init : unsupported revision %d at 0x%p, mail [e-mail]\n",
				check->fields.revision, check);
			continue;
		}
		printk ("pcibios_init : BIOS32 Service Directory structure at 0x%p\n", check);
		if (!bios32_entry) {
			if (check->fields.entry >= 0x100000) {
				printk("pcibios_init: entry in high memory, trying direct PCI access\n");
				access_pci = check_direct_pci();
			} else {
				bios32_entry = check->fields.entry;
				printk ("pcibios_init : BIOS32 Service Directory entry at 0x%lx\n", bios32_entry);
				bios32_indirect.address = bios32_entry;
			}
		}
	}
	if (bios32_entry && check_pcibios())
 		access_pci = &pci_bios_access;
#endif
	return memory_start;
}