drivers.c

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/*
 * drivers.c
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 *
 * Copyright (c) 1999 The Puffin Group
 * Copyright (c) 2001 Matthew Wilcox for Hewlett Packard
 * Copyright (c) 2001 Helge Deller <[email protected]>
 * Copyright (c) 2001,2002 Ryan Bradetich 
 * Copyright (c) 2004-2005 Thibaut VARENE <[email protected]>
 * 
 * The file handles registering devices and drivers, then matching them.
 * It's the closest we get to a dating agency.
 *
 * If you're thinking about modifying this file, here are some gotchas to
 * bear in mind:
 *  - 715/Mirage device paths have a dummy device between Lasi and its children
 *  - The EISA adapter may show up as a sibling or child of Wax
 *  - Dino has an optionally functional serial port.  If firmware enables it,
 *    it shows up as a child of Dino.  If firmware disables it, the buswalk
 *    finds it and it shows up as a child of Cujo
 *  - Dino has both parisc and pci devices as children
 *  - parisc devices are discovered in a random order, including children
 *    before parents in some cases.
 */

#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/export.h>
#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/pdc.h>
#include <asm/parisc-device.h>

/* See comments in include/asm-parisc/pci.h */
struct hppa_dma_ops *hppa_dma_ops __read_mostly;
EXPORT_SYMBOL(hppa_dma_ops);

static struct device root = {
    .init_name = "parisc",
};

static inline int check_dev(struct device *dev)
{
    if (dev->bus == &parisc_bus_type) {
        struct parisc_device *pdev;
        pdev = to_parisc_device(dev);
        return pdev->id.hw_type != HPHW_FAULTY;
    }
    return 1;
}

static struct device *
parse_tree_node(struct device *parent, int index, struct hardware_path *modpath);

struct recurse_struct {
    void * obj;
    int (*fn)(struct device *, void *);
};

static int descend_children(struct device * dev, void * data)
{
    struct recurse_struct * recurse_data = (struct recurse_struct *)data;

    if (recurse_data->fn(dev, recurse_data->obj))
        return 1;
    else
        return device_for_each_child(dev, recurse_data, descend_children);
}

static int for_each_padev(int (*fn)(struct device *, void *), void * data)
{
    struct recurse_struct recurse_data = {
        .obj    = data,
        .fn = fn,
    };
    return device_for_each_child(&root, &recurse_data, descend_children);
}

static int match_device(struct parisc_driver *driver, struct parisc_device *dev)
{
    const struct parisc_device_id *ids;

    for (ids = driver->id_table; ids->sversion; ids++) {
        if ((ids->sversion != SVERSION_ANY_ID) &&
            (ids->sversion != dev->id.sversion))
            continue;

        if ((ids->hw_type != HWTYPE_ANY_ID) &&
            (ids->hw_type != dev->id.hw_type))
            continue;

        if ((ids->hversion != HVERSION_ANY_ID) &&
            (ids->hversion != dev->id.hversion))
            continue;

        return 1;
    }
    return 0;
}

static int parisc_driver_probe(struct device *dev)
{
    int rc;
    struct parisc_device *pa_dev = to_parisc_device(dev);
    struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);

    rc = pa_drv->probe(pa_dev);

    if (!rc)
        pa_dev->driver = pa_drv;

    return rc;
}

static int parisc_driver_remove(struct device *dev)
{
    struct parisc_device *pa_dev = to_parisc_device(dev);
    struct parisc_driver *pa_drv = to_parisc_driver(dev->driver);
    if (pa_drv->remove)
        pa_drv->remove(pa_dev);

    return 0;
}
    

int register_parisc_driver(struct parisc_driver *driver)
{
    /* FIXME: we need this because apparently the sti
     * driver can be registered twice */
    if(driver->drv.name) {
        printk(KERN_WARNING 
               "BUG: skipping previously registered driver %s\n",
               driver->name);
        return 1;
    }

    if (!driver->probe) {
        printk(KERN_WARNING 
               "BUG: driver %s has no probe routine\n",
               driver->name);
        return 1;
    }

    driver->drv.bus = &parisc_bus_type;

    /* We install our own probe and remove routines */
    WARN_ON(driver->drv.probe != NULL);
    WARN_ON(driver->drv.remove != NULL);

    driver->drv.name = driver->name;

    return driver_register(&driver->drv);
}
EXPORT_SYMBOL(register_parisc_driver);


struct match_count {
    struct parisc_driver * driver;
    int count;
};

static int match_and_count(struct device * dev, void * data)
{
    struct match_count * m = data;
    struct parisc_device * pdev = to_parisc_device(dev);

    if (check_dev(dev)) {
        if (match_device(m->driver, pdev))
            m->count++;
    }
    return 0;
}

int count_parisc_driver(struct parisc_driver *driver)
{
    struct match_count m = {
        .driver = driver,
        .count  = 0,
    };

    for_each_padev(match_and_count, &m);

    return m.count;
}



int unregister_parisc_driver(struct parisc_driver *driver)
{
    driver_unregister(&driver->drv);
    return 0;
}
EXPORT_SYMBOL(unregister_parisc_driver);

struct find_data {
    unsigned long hpa;
    struct parisc_device * dev;
};

static int find_device(struct device * dev, void * data)
{
    struct parisc_device * pdev = to_parisc_device(dev);
    struct find_data * d = (struct find_data*)data;

    if (check_dev(dev)) {
        if (pdev->hpa.start == d->hpa) {
            d->dev = pdev;
            return 1;
        }
    }
    return 0;
}

static struct parisc_device *find_device_by_addr(unsigned long hpa)
{
    struct find_data d = {
        .hpa    = hpa,
    };
    int ret;

    ret = for_each_padev(find_device, &d);
    return ret ? d.dev : NULL;
}

const struct parisc_device *
find_pa_parent_type(const struct parisc_device *padev, int type)
{
    const struct device *dev = &padev->dev;
    while (dev != &root) {
        struct parisc_device *candidate = to_parisc_device(dev);
        if (candidate->id.hw_type == type)
            return candidate;
        dev = dev->parent;
    }

    return NULL;
}

#ifdef CONFIG_PCI
static inline int is_pci_dev(struct device *dev)
{
    return dev->bus == &pci_bus_type;
}
#else
static inline int is_pci_dev(struct device *dev)
{
    return 0;
}
#endif

/*
 * get_node_path fills in @path with the firmware path to the device.
 * Note that if @node is a parisc device, we don't fill in the 'mod' field.
 * This is because both callers pass the parent and fill in the mod
 * themselves.  If @node is a PCI device, we do fill it in, even though this
 * is inconsistent.
 */
static void get_node_path(struct device *dev, struct hardware_path *path)
{
    int i = 5;
    memset(&path->bc, -1, 6);

    if (is_pci_dev(dev)) {
        unsigned int devfn = to_pci_dev(dev)->devfn;
        path->mod = PCI_FUNC(devfn);
        path->bc[i--] = PCI_SLOT(devfn);
        dev = dev->parent;
    }

    while (dev != &root) {
        if (is_pci_dev(dev)) {
            unsigned int devfn = to_pci_dev(dev)->devfn;
            path->bc[i--] = PCI_SLOT(devfn) | (PCI_FUNC(devfn)<< 5);
        } else if (dev->bus == &parisc_bus_type) {
            path->bc[i--] = to_parisc_device(dev)->hw_path;
        }
        dev = dev->parent;
    }
}

static char *print_hwpath(struct hardware_path *path, char *output)
{
    int i;
    for (i = 0; i < 6; i++) {
        if (path->bc[i] == -1)
            continue;
        output += sprintf(output, "%u/", (unsigned char) path->bc[i]);
    }
    output += sprintf(output, "%u", (unsigned char) path->mod);
    return output;
}

char *print_pa_hwpath(struct parisc_device *dev, char *output)
{
    struct hardware_path path;

    get_node_path(dev->dev.parent, &path);
    path.mod = dev->hw_path;
    return print_hwpath(&path, output);
}
EXPORT_SYMBOL(print_pa_hwpath);

#if defined(CONFIG_PCI) || defined(CONFIG_ISA)

void get_pci_node_path(struct pci_dev *pdev, struct hardware_path *path)
{
    get_node_path(&pdev->dev, path);
}
EXPORT_SYMBOL(get_pci_node_path);

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);
}
EXPORT_SYMBOL(print_pci_hwpath);

#endif /* defined(CONFIG_PCI) || defined(CONFIG_ISA) */

static void setup_bus_id(struct parisc_device *padev)
{
    struct hardware_path path;
    char name[20];
    char *output = name;
    int i;

    get_node_path(padev->dev.parent, &path);

    for (i = 0; i < 6; i++) {
        if (path.bc[i] == -1)
            continue;
        output += sprintf(output, "%u:", (unsigned char) path.bc[i]);
    }
    sprintf(output, "%u", (unsigned char) padev->hw_path);
    dev_set_name(&padev->dev, name);
}

struct parisc_device * create_tree_node(char id, struct device *parent)
{
    struct parisc_device *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
    if (!dev)
        return NULL;

    dev->hw_path = id;
    dev->id.hw_type = HPHW_FAULTY;

    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;
    if (device_register(&dev->dev)) {
        kfree(dev);
        return NULL;
    }

    return dev;
}

struct match_id_data {
    char id;
    struct parisc_device * dev;
};

static int match_by_id(struct device * dev, void * data)
{
    struct parisc_device * pdev = to_parisc_device(dev);
    struct match_id_data * d = data;

    if (pdev->hw_path == d->id) {
        d->dev = pdev;
        return 1;
    }
    return 0;
}

static struct parisc_device * alloc_tree_node(struct device *parent, char id)
{
    struct match_id_data d = {
        .id = id,
    };
    if (device_for_each_child(parent, &d, match_by_id))
        return d.dev;
    else
        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) {
        printk(KERN_ERR "Two devices have hardware path [%s].  "
                "IODC data for second device: "
                "%02x%02x%02x%02x%02x%02x\n"
                "Rearranging GSC cards sometimes helps\n",
            parisc_pathname(dev), iodc_data[0], iodc_data[1],
            iodc_data[3], iodc_data[4], iodc_data[5], iodc_data[6]);
        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.name = parisc_pathname(dev);
    dev->hpa.start = hpa;
    /* This is awkward.  The STI spec says that gfx devices may occupy
     * 32MB or 64MB.  Unfortunately, we don't know how to tell whether
     * it's the former or the latter.  Assumptions either way can hurt us.
     */
    if (hpa == 0xf4000000 || hpa == 0xf8000000) {
        dev->hpa.end = hpa + 0x03ffffff;
    } else if (hpa == 0xf6000000 || hpa == 0xfa000000) {
        dev->hpa.end = hpa + 0x01ffffff;
    } else {
        dev->hpa.end = hpa + 0xfff;
    }
    dev->hpa.flags = IORESOURCE_MEM;
    name = parisc_hardware_description(&dev->id);
    if (name) {
        strlcpy(dev->name, name, sizeof(dev->name));
    }

    /* Silently fail things like mouse ports which are subsumed within
     * the keyboard controller
     */
    if ((hpa & 0xfff) == 0 && insert_resource(&iomem_resource, &dev->hpa))
        printk("Unable to claim HPA %lx for device %s\n",
                hpa, 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));
}

static ssize_t make_modalias(struct device *dev, char *buf)
{
    const struct parisc_device *padev = to_parisc_device(dev);
    const struct parisc_device_id *id = &padev->id;

    return sprintf(buf, "parisc:t%02Xhv%04Xrev%02Xsv%08X\n",
        (u8)id->hw_type, (u16)id->hversion, (u8)id->hversion_rev,
        (u32)id->sversion);
}

static int parisc_uevent(struct device *dev, struct kobj_uevent_env *env)
{
    const struct parisc_device *padev;
    char modalias[40];

    if (!dev)
        return -ENODEV;

    padev = to_parisc_device(dev);
    if (!padev)
        return -ENODEV;

    if (add_uevent_var(env, "PARISC_NAME=%s", padev->name))
        return -ENOMEM;

    make_modalias(dev, modalias);
    if (add_uevent_var(env, "MODALIAS=%s", modalias))
        return -ENOMEM;

    return 0;
}

#define pa_dev_attr(name, field, format_string)             \
static ssize_t name##_show(struct device *dev, struct device_attribute *attr, 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 ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf)
{
    return make_modalias(dev, buf);
}

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

struct bus_type parisc_bus_type = {
    .name = "parisc",
    .match = parisc_generic_match,
    .uevent = parisc_uevent,
    .dev_attrs = parisc_device_attrs,
    .probe = parisc_driver_probe,
    .remove = parisc_driver_remove,
};

int register_parisc_device(struct parisc_device *dev)
{
    if (!dev)
        return 0;

    if (dev->driver)
        return 1;

    return 0;
}

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);
}

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);
}

struct parse_tree_data {
    int index;
    struct hardware_path * modpath;
    struct device * dev;
};

static int check_parent(struct device * dev, void * data)
{
    struct parse_tree_data * d = data;

    if (check_dev(dev)) {
        if (dev->bus == &parisc_bus_type) {
            if (match_parisc_device(dev, d->index, d->modpath))
                d->dev = dev;
        } else if (is_pci_dev(dev)) {
            if (match_pci_device(dev, d->index, d->modpath))
                d->dev = dev;
        } else if (dev->bus == NULL) {
            /* we are on a bus bridge */
            struct device *new = parse_tree_node(dev, d->index, d->modpath);
            if (new)
                d->dev = new;
        }
    }
    return d->dev != NULL;
}

static struct device *
parse_tree_node(struct device *parent, int index, struct hardware_path *modpath)
{
    struct parse_tree_data d = {
        .index          = index,
        .modpath        = modpath,
    };

    struct recurse_struct recurse_data = {
        .obj    = &d,
        .fn = check_parent,
    };

    if (device_for_each_child(parent, &recurse_data, descend_children))
        /* nothing */;

    return d.dev;
}

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);

void device_to_hwpath(struct device *dev, struct hardware_path *path)
{
    struct parisc_device *padev;
    if (dev->bus == &parisc_bus_type) {
        padev = to_parisc_device(dev);
        get_node_path(dev->parent, path);
        path->mod = padev->hw_path;
    } else if (is_pci_dev(dev)) {
        get_node_path(dev, path);
    }
}
EXPORT_SYMBOL(device_to_hwpath);

#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.start + 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.start + IO_IO_LOW)
#define READ_IO_IO_HIGH(dev) (unsigned long)(signed int)gsc_readl(dev->hpa.start + 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);
}

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)

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%p [%s] { %d, 0x%x, 0x%.3x, 0x%.5x }",
        ++count, dev->name, (void*) dev->hpa.start, 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");
}

void init_parisc_bus(void)
{
    if (bus_register(&parisc_bus_type))
        panic("Could not register PA-RISC bus type\n");
    if (device_register(&root))
        panic("Could not register PA-RISC root device\n");
    get_device(&root);
}


static int print_one_device(struct device * dev, void * data)
{
    struct parisc_device * pdev = to_parisc_device(dev);

    if (check_dev(dev))
        print_parisc_device(pdev);
    return 0;
}

void print_parisc_devices(void)
{
    for_each_padev(print_one_device, NULL);
}