drivers.c

一个2.4.21版本的嵌入式linux内核

}

/**
 * print_pci_hwpath - Returns hardware path for PCI devices
 * dev: The device to return the path for
 * output: Pointer to a previously-allocated array to place the path in.
 *
 * This function fills in the output array with a human-readable path
 * to a PCI device.  This string is compatible with that used by PDC, and
 * may be printed on the outside of the box.
 */
char *print_pci_hwpath(struct pci_dev *dev, char *output)
{
	struct hardware_path path;

	get_pci_node_path(dev, &path);
	return print_hwpath(&path, output);
}
#endif /* defined(CONFIG_PCI) || defined(CONFIG_ISA) */


struct parisc_device * create_tree_node(char id, struct parisc_device *parent,
		struct parisc_device **insert)
{
	struct parisc_device *dev = kmalloc(sizeof(*dev), GFP_KERNEL);
	if (!dev)
		return NULL;
	memset(dev, 0, sizeof(*dev));
	dev->hw_path = id;
	dev->id.hw_type = HPHW_FAULTY;
	dev->parent = parent;
	dev->sibling = *insert;
	*insert = dev;
	return dev;
}

/**
 * alloc_tree_node - returns a device entry in the iotree
 * @parent: the parent node in the tree
 * @id: the element of the module path for this entry
 *
 * Checks all the children of @parent for a matching @id.  If none
 * found, it allocates a new device and returns it.
 */
struct parisc_device *
alloc_tree_node(struct parisc_device *parent, char id)
{
	struct parisc_device *prev;
	if ((!parent->child) || (parent->child->hw_path > id)) {
		return create_tree_node(id, parent, &parent->child);
	}

	prev = parent->child;
	if (prev->hw_path == id)
		return prev;

	while (prev->sibling && prev->sibling->hw_path < id) {
		prev = prev->sibling;
	}

	if ((prev->sibling) && (prev->sibling->hw_path == id))
		return prev->sibling;

	return create_tree_node(id, parent, &prev->sibling);
}

static struct parisc_device *find_parisc_device(struct hardware_path *modpath)
{
	int i;
	struct parisc_device *parent = &root;
	for (i = 0; i < 6; i++) {
		if (modpath->bc[i] == -1)
			continue;
		parent = alloc_tree_node(parent, modpath->bc[i]);
	}
	return alloc_tree_node(parent, modpath->mod);
}

struct parisc_device *
alloc_pa_dev(unsigned long hpa, struct hardware_path *mod_path)
{
	int status;
	unsigned long bytecnt;
	u8 iodc_data[32];
	struct parisc_device *dev;
	const char *name;

	/* Check to make sure this device has not already been added - Ryan */
	if (find_device_by_addr(hpa) != NULL)
		return NULL;

	status = pdc_iodc_read(&bytecnt, hpa, 0, &iodc_data, 32);
	if (status != PDC_OK)
		return NULL;

	dev = find_parisc_device(mod_path);
	if (dev->id.hw_type != HPHW_FAULTY) {
		char p[64];
		print_pa_hwpath(dev, p);
		printk("Two devices have hardware path %s.  Please file a bug with HP.\n"
			"In the meantime, you could try rearranging your cards.\n", p);
		return NULL;
	}

	dev->id.hw_type = iodc_data[3] & 0x1f;
	dev->id.hversion = (iodc_data[0] << 4) | ((iodc_data[1] & 0xf0) >> 4);
	dev->id.hversion_rev = iodc_data[1] & 0x0f;
	dev->id.sversion = ((iodc_data[4] & 0x0f) << 16) |
			(iodc_data[5] << 8) | iodc_data[6];
	dev->hpa = hpa;
	name = parisc_hardware_description(&dev->id);
	if (name) {
		strncpy(dev->name, name, sizeof(dev->name)-1);
	}

	return dev;
}

/**
 * register_parisc_device - Locate a driver to manage this device.
 * @dev: The parisc device.
 *
 * Search the driver list for a driver that is willing to manage
 * this device.
 */
int register_parisc_device(struct parisc_device *dev)
{
	struct parisc_driver *driver;

	if (!dev)
		return 0;

	if (dev->driver)
		return 1;
	
	spin_lock(&pa_lock);

	/* Locate a driver which agrees to manage this device.  */
	for (driver = pa_drivers; driver; driver = driver->next) {
		if (!match_device(driver,dev))
			continue;
		if (driver->probe(dev) == 0)
			break;
	}

	if (driver != NULL) {
		claim_device(driver, dev);
	}
	spin_unlock(&pa_lock);
	return driver != NULL;
}

#define BC_PORT_MASK 0x8
#define BC_LOWER_PORT 0x8


#define BUS_CONVERTER(dev) \
        ((dev->id.hw_type == HPHW_IOA) || (dev->id.hw_type == HPHW_BCPORT))

#define IS_LOWER_PORT(dev) \
        ((gsc_readl(&((struct bc_module *)dev->hpa)->io_status) \
                & BC_PORT_MASK) == BC_LOWER_PORT)

#define READ_IO_IO_LOW(dev) \
	(dev->id.hw_type == HPHW_IOA ? \
	        __raw_readl((unsigned long)&((struct bc_module *)dev->hpa)->io_io_low) << 16 : \
	        __raw_readl((unsigned long)&((struct bc_module *)dev->hpa)->io_io_low))

#define READ_IO_IO_HIGH(dev) \
	(dev->id.hw_type == HPHW_IOA ? \
	        __raw_readl((unsigned long)&((struct bc_module *)dev->hpa)->io_io_high) << 16 : \
	        __raw_readl((unsigned long)&((struct bc_module *)dev->hpa)->io_io_high))


static void walk_native_bus(unsigned long io_io_low, unsigned long io_io_high, 
			    struct parisc_device *parent);

#define FLEX_MASK (unsigned long)0xfffffffffffc0000


void walk_lower_bus(struct parisc_device *dev)
{
	unsigned long io_io_low, io_io_high;

	if(!BUS_CONVERTER(dev) || IS_LOWER_PORT(dev))
		return;

	io_io_low = ((unsigned long)(signed int)READ_IO_IO_LOW(dev) + ~FLEX_MASK) & FLEX_MASK;
	io_io_high = ((unsigned long)(signed int)READ_IO_IO_HIGH(dev) + ~FLEX_MASK) & FLEX_MASK;

	walk_native_bus(io_io_low, io_io_high, dev);
}

#define MAX_NATIVE_DEVICES 64
#define NATIVE_DEVICE_OFFSET 0x1000

/**
 * walk_native_bus -- Probe a bus for devices
 * @io_io_low: Base address of this bus.
 * @io_io_high: Last address of this bus.
 * @parent: The parent bus device.
 * 
 * A native bus (eg Runway or GSC) may have up to 64 devices on it,
 * spaced at intervals of 0x1000 bytes.  PDC may not inform us of these
 * devices, so we have to probe for them.  Unfortunately, we may find
 * devices which are not physically connected (such as extra serial &
 * keyboard ports).  This problem is not yet solved.
 */
static void walk_native_bus(unsigned long io_io_low, unsigned long io_io_high,
			    struct parisc_device *parent)
{
	int i, devices_found = 0;
	unsigned long hpa = io_io_low;
	struct hardware_path path;

	get_node_path(parent, &path);
	do {
		for (i = 0; i < MAX_NATIVE_DEVICES; i++, hpa += NATIVE_DEVICE_OFFSET) {
			struct parisc_device *dev;

			/* Was the device already added by Firmware? */
			dev = find_device_by_addr(hpa);
			if (!dev) {
				path.mod = i;
				dev = alloc_pa_dev(hpa, &path);
				if (!dev)
					continue;

				register_parisc_device(dev);
				devices_found++;
			}
			walk_lower_bus(dev);
		}
	} while (!devices_found && hpa < io_io_high);
}

#define CENTRAL_BUS_ADDR (unsigned long) 0xfffffffffff80000

/**
 * walk_central_bus - Find devices attached to the central bus
 *
 * PDC doesn't tell us about all devices in the system.  This routine
 * finds devices connected to the central bus.
 */
void walk_central_bus(void)
{
	walk_native_bus(CENTRAL_BUS_ADDR, 
			CENTRAL_BUS_ADDR + (MAX_NATIVE_DEVICES * NATIVE_DEVICE_OFFSET),
			&root);
}

void fixup_child_irqs(struct parisc_device *parent, int base,
			int (*choose_irq)(struct parisc_device *))
{
	struct parisc_device *dev;

	if (!parent->child)
		return;

	for (dev = check_dev(parent->child); dev; dev = dev->sibling) {
		int irq = choose_irq(dev);
		if (irq > 0) {
#ifdef __LP64__
			irq += 32;
#endif
			dev->irq = base + irq;
		}
	}
}

static void print_parisc_device(struct parisc_device *dev)
{
	char hw_path[64];
	static int count;

	print_pa_hwpath(dev, hw_path);
	printk(KERN_INFO "%d. %s (%d) at 0x%lx [%s], versions 0x%x, 0x%x, 0x%x",
		++count, dev->name, dev->id.hw_type, dev->hpa, hw_path,
		dev->id.hversion, dev->id.hversion_rev, dev->id.sversion);

	if (dev->num_addrs) {
		int k;
		printk(",  additional addresses: ");
		for (k = 0; k < dev->num_addrs; k++)
			printk("0x%lx ", dev->addr[k]);
	}
	printk("\n");
}

void print_subdevices(struct parisc_device *parent)
{
	struct parisc_device *dev;
	for (dev = parent->child; dev != parent->sibling; dev = next_dev(dev)) {
		print_parisc_device(dev);
	}
}

/**
 * print_parisc_devices - Print out a list of devices found in this system
 */
void print_parisc_devices(void)
{
	struct parisc_device *dev;
	for_each_padev(dev) {
		print_parisc_device(dev);
	}
}