drivers.c

h内核

	dev->dev.parent = parent;
	setup_bus_id(dev);

	dev->dev.bus = &parisc_bus_type;
	dev->dma_mask = 0xffffffffUL;	/* PARISC devices are 32-bit */

	/* make the generic dma mask a pointer to the parisc one */
	dev->dev.dma_mask = &dev->dma_mask;
	dev->dev.coherent_dma_mask = dev->dma_mask;
	device_register(&dev->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.
 */
static struct parisc_device * alloc_tree_node(struct device *parent, char id)
{
	struct device *dev;

	list_for_each_entry(dev, &parent->children, node) {
		struct parisc_device *padev = to_parisc_device(dev);
		if (padev->hw_path == id)
			return padev;
	}

	return create_tree_node(id, parent);
}

static struct parisc_device *create_parisc_device(struct hardware_path *modpath)
{
	int i;
	struct device *parent = &root;
	for (i = 0; i < 6; i++) {
		if (modpath->bc[i] == -1)
			continue;
		parent = &alloc_tree_node(parent, modpath->bc[i])->dev;
	}
	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 = create_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) {
		strlcpy(dev->name, name, sizeof(dev->name));
	}

	return dev;
}

static int parisc_generic_match(struct device *dev, struct device_driver *drv)
{
	return match_device(to_parisc_driver(drv), to_parisc_device(dev));
}

#define pa_dev_attr(name, field, format_string)				\
static ssize_t name##_show(struct device *dev, char *buf)		\
{									\
	struct parisc_device *padev = to_parisc_device(dev);		\
	return sprintf(buf, format_string, padev->field);		\
}

#define pa_dev_attr_id(field, format) pa_dev_attr(field, id.field, format)

pa_dev_attr(irq, irq, "%u\n");
pa_dev_attr_id(hw_type, "0x%02x\n");
pa_dev_attr(rev, id.hversion_rev, "0x%x\n");
pa_dev_attr_id(hversion, "0x%03x\n");
pa_dev_attr_id(sversion, "0x%05x\n");

static struct device_attribute parisc_device_attrs[] = {
	__ATTR_RO(irq),
	__ATTR_RO(hw_type),
	__ATTR_RO(rev),
	__ATTR_RO(hversion),
	__ATTR_RO(sversion),
	__ATTR_NULL,
};

struct bus_type parisc_bus_type = {
	.name = "parisc",
	.match = parisc_generic_match,
	.dev_attrs = parisc_device_attrs,
};

/**
 * 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)
{
	if (!dev)
		return 0;

	if (dev->driver)
		return 1;

	return 0;
}

/**
 * match_pci_device - Matches a pci device against a given hardware path
 * entry.
 * @dev: the generic device (known to be contained by a pci_dev).
 * @index: the current BC index
 * @modpath: the hardware path.
 * @return: true if the device matches the hardware path.
 */
static int match_pci_device(struct device *dev, int index,
		struct hardware_path *modpath)
{
	struct pci_dev *pdev = to_pci_dev(dev);
	int id;

	if (index == 5) {
		/* we are at the end of the path, and on the actual device */
		unsigned int devfn = pdev->devfn;
		return ((modpath->bc[5] == PCI_SLOT(devfn)) &&
					(modpath->mod == PCI_FUNC(devfn)));
	}

	id = PCI_SLOT(pdev->devfn) | (PCI_FUNC(pdev->devfn) << 5);
	return (modpath->bc[index] == id);
}

/**
 * match_parisc_device - Matches a parisc device against a given hardware
 * path entry.
 * @dev: the generic device (known to be contained by a parisc_device).
 * @index: the current BC index
 * @modpath: the hardware path.
 * @return: true if the device matches the hardware path.
 */
static int match_parisc_device(struct device *dev, int index,
		struct hardware_path *modpath)
{
	struct parisc_device *curr = to_parisc_device(dev);
	char id = (index == 6) ? modpath->mod : modpath->bc[index];

	return (curr->hw_path == id);
}

/**
 * parse_tree_node - returns a device entry in the iotree
 * @parent: the parent node in the tree
 * @index: the current BC index
 * @modpath: the hardware_path struct to match a device against
 * @return: The corresponding device if found, NULL otherwise.
 *
 * Checks all the children of @parent for a matching @id.  If none
 * found, it returns NULL.
 */
static struct device *
parse_tree_node(struct device *parent, int index, struct hardware_path *modpath)
{
	struct device *device;
	 
	list_for_each_entry(device, &parent->children, node) {
		if (device->bus == &parisc_bus_type) {
			if (match_parisc_device(device, index, modpath))
				return device;
		} else if (is_pci_dev(device)) {
			if (match_pci_device(device, index, modpath))
				return device;
		} else if (device->bus == NULL) {
			/* we are on a bus bridge */
			struct device *new = parse_tree_node(device, index, modpath);
			if (new)
				return new;
		}
	}

	return NULL;
}

/**
 * hwpath_to_device - Finds the generic device corresponding to a given hardware path.
 * @modpath: the hardware path.
 * @return: The target device, NULL if not found.
 */
struct device *hwpath_to_device(struct hardware_path *modpath)
{
	int i;
	struct device *parent = &root;
	for (i = 0; i < 6; i++) {
		if (modpath->bc[i] == -1)
			continue;
		parent = parse_tree_node(parent, i, modpath);
		if (!parent)
			return NULL;
	}
	if (is_pci_dev(parent)) /* pci devices already parse MOD */
		return parent;
	else
		return parse_tree_node(parent, 6, modpath);
}
EXPORT_SYMBOL(hwpath_to_device);

#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(dev->hpa + offsetof(struct bc_module, io_status)) \
                & BC_PORT_MASK) == BC_LOWER_PORT)

#define MAX_NATIVE_DEVICES 64
#define NATIVE_DEVICE_OFFSET 0x1000

#define FLEX_MASK 	F_EXTEND(0xfffc0000)
#define IO_IO_LOW	offsetof(struct bc_module, io_io_low)
#define IO_IO_HIGH	offsetof(struct bc_module, io_io_high)
#define READ_IO_IO_LOW(dev)  (unsigned long)(signed int)gsc_readl(dev->hpa + IO_IO_LOW)
#define READ_IO_IO_HIGH(dev) (unsigned long)(signed int)gsc_readl(dev->hpa + IO_IO_HIGH)

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

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;

	if(dev->id.hw_type == HPHW_IOA) {
		io_io_low = (unsigned long)(signed int)(READ_IO_IO_LOW(dev) << 16);
		io_io_high = io_io_low + MAX_NATIVE_DEVICES * NATIVE_DEVICE_OFFSET;
	} else {
		io_io_low = (READ_IO_IO_LOW(dev) + ~FLEX_MASK) & FLEX_MASK;
		io_io_high = (READ_IO_IO_HIGH(dev)+ ~FLEX_MASK) & FLEX_MASK;
	}

	walk_native_bus(io_io_low, io_io_high, &dev->dev);
}

/**
 * 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 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 F_EXTEND(0xfff80000)

/**
 * 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);
}

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 at 0x%lx [%s] { %d, 0x%x, 0x%.3x, 0x%.5x }",
		++count, dev->name, dev->hpa, hw_path, dev->id.hw_type,
		dev->id.hversion_rev, dev->id.hversion, 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");
}

/**
 * init_parisc_bus - Some preparation to be done before inventory
 */
void init_parisc_bus(void)
{
	bus_register(&parisc_bus_type);
	device_register(&root);
	get_device(&root);
}

/**
 * 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);
	}
}