main.c

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/*
 * Sonics Silicon Backplane
 * Subsystem core
 *
 * Copyright 2005, Broadcom Corporation
 * Copyright 2006, 2007, Michael Buesch <[e-mail]>
 *
 * Licensed under the GNU/GPL. See COPYING for details.
 */

#include "ssb_private.h"

#include <linux/delay.h>
#include <linux/io.h>
#include <linux/ssb/ssb.h>
#include <linux/ssb/ssb_regs.h>
#include <linux/dma-mapping.h>
#include <linux/pci.h>

#include <pcmcia/cs_types.h>
#include <pcmcia/cs.h>
#include <pcmcia/cistpl.h>
#include <pcmcia/ds.h>


MODULE_DESCRIPTION("Sonics Silicon Backplane driver");
MODULE_LICENSE("GPL");


/* Temporary list of yet-to-be-attached buses */
static LIST_HEAD(attach_queue);
/* List if running buses */
static LIST_HEAD(buses);
/* Software ID counter */
static unsigned int next_busnumber;
/* buses_mutes locks the two buslists and the next_busnumber.
 * Don't lock this directly, but use ssb_buses_[un]lock() below. */
static DEFINE_MUTEX(buses_mutex);

/* There are differences in the codeflow, if the bus is
 * initialized from early boot, as various needed services
 * are not available early. This is a mechanism to delay
 * these initializations to after early boot has finished.
 * It's also used to avoid mutex locking, as that's not
 * available and needed early. */
static bool ssb_is_early_boot = 1;

static void ssb_buses_lock(void);
static void ssb_buses_unlock(void);


#ifdef CONFIG_SSB_PCIHOST
struct ssb_bus *ssb_pci_dev_to_bus(struct pci_dev *pdev)
{
	struct ssb_bus *bus;

	ssb_buses_lock();
	list_for_each_entry(bus, &buses, list) {
		if (bus->bustype == SSB_BUSTYPE_PCI &&
		    bus->host_pci == pdev)
			goto found;
	}
	bus = NULL;
found:
	ssb_buses_unlock();

	return bus;
}
#endif /* CONFIG_SSB_PCIHOST */

static struct ssb_device *ssb_device_get(struct ssb_device *dev)
{
	if (dev)
		get_device(dev->dev);
	return dev;
}

static void ssb_device_put(struct ssb_device *dev)
{
	if (dev)
		put_device(dev->dev);
}

static int ssb_bus_resume(struct ssb_bus *bus)
{
	int err;

	ssb_pci_xtal(bus, SSB_GPIO_XTAL | SSB_GPIO_PLL, 1);
	err = ssb_pcmcia_init(bus);
	if (err) {
		/* No need to disable XTAL, as we don't have one on PCMCIA. */
		return err;
	}
	ssb_chipco_resume(&bus->chipco);

	return 0;
}

static int ssb_device_resume(struct device *dev)
{
	struct ssb_device *ssb_dev = dev_to_ssb_dev(dev);
	struct ssb_driver *ssb_drv;
	struct ssb_bus *bus;
	int err = 0;

	bus = ssb_dev->bus;
	if (bus->suspend_cnt == bus->nr_devices) {
		err = ssb_bus_resume(bus);
		if (err)
			return err;
	}
	bus->suspend_cnt--;
	if (dev->driver) {
		ssb_drv = drv_to_ssb_drv(dev->driver);
		if (ssb_drv && ssb_drv->resume)
			err = ssb_drv->resume(ssb_dev);
		if (err)
			goto out;
	}
out:
	return err;
}

static void ssb_bus_suspend(struct ssb_bus *bus, pm_message_t state)
{
	ssb_chipco_suspend(&bus->chipco, state);
	ssb_pci_xtal(bus, SSB_GPIO_XTAL | SSB_GPIO_PLL, 0);

	/* Reset HW state information in memory, so that HW is
	 * completely reinitialized on resume. */
	bus->mapped_device = NULL;
#ifdef CONFIG_SSB_DRIVER_PCICORE
	bus->pcicore.setup_done = 0;
#endif
#ifdef CONFIG_SSB_DEBUG
	bus->powered_up = 0;
#endif
}

static int ssb_device_suspend(struct device *dev, pm_message_t state)
{
	struct ssb_device *ssb_dev = dev_to_ssb_dev(dev);
	struct ssb_driver *ssb_drv;
	struct ssb_bus *bus;
	int err = 0;

	if (dev->driver) {
		ssb_drv = drv_to_ssb_drv(dev->driver);
		if (ssb_drv && ssb_drv->suspend)
			err = ssb_drv->suspend(ssb_dev, state);
		if (err)
			goto out;
	}

	bus = ssb_dev->bus;
	bus->suspend_cnt++;
	if (bus->suspend_cnt == bus->nr_devices) {
		/* All devices suspended. Shutdown the bus. */
		ssb_bus_suspend(bus, state);
	}

out:
	return err;
}

#ifdef CONFIG_SSB_PCIHOST
int ssb_devices_freeze(struct ssb_bus *bus)
{
	struct ssb_device *dev;
	struct ssb_driver *drv;
	int err = 0;
	int i;
	pm_message_t state = PMSG_FREEZE;

	/* First check that we are capable to freeze all devices. */
	for (i = 0; i < bus->nr_devices; i++) {
		dev = &(bus->devices[i]);
		if (!dev->dev ||
		    !dev->dev->driver ||
		    !device_is_registered(dev->dev))
			continue;
		drv = drv_to_ssb_drv(dev->dev->driver);
		if (!drv)
			continue;
		if (!drv->suspend) {
			/* Nope, can't suspend this one. */
			return -EOPNOTSUPP;
		}
	}
	/* Now suspend all devices */
	for (i = 0; i < bus->nr_devices; i++) {
		dev = &(bus->devices[i]);
		if (!dev->dev ||
		    !dev->dev->driver ||
		    !device_is_registered(dev->dev))
			continue;
		drv = drv_to_ssb_drv(dev->dev->driver);
		if (!drv)
			continue;
		err = drv->suspend(dev, state);
		if (err) {
			ssb_printk(KERN_ERR PFX "Failed to freeze device %s\n",
				   dev->dev->bus_id);
			goto err_unwind;
		}
	}

	return 0;
err_unwind:
	for (i--; i >= 0; i--) {
		dev = &(bus->devices[i]);
		if (!dev->dev ||
		    !dev->dev->driver ||
		    !device_is_registered(dev->dev))
			continue;
		drv = drv_to_ssb_drv(dev->dev->driver);
		if (!drv)
			continue;
		if (drv->resume)
			drv->resume(dev);
	}
	return err;
}

int ssb_devices_thaw(struct ssb_bus *bus)
{
	struct ssb_device *dev;
	struct ssb_driver *drv;
	int err;
	int i;

	for (i = 0; i < bus->nr_devices; i++) {
		dev = &(bus->devices[i]);
		if (!dev->dev ||
		    !dev->dev->driver ||
		    !device_is_registered(dev->dev))
			continue;
		drv = drv_to_ssb_drv(dev->dev->driver);
		if (!drv)
			continue;
		if (SSB_WARN_ON(!drv->resume))
			continue;
		err = drv->resume(dev);
		if (err) {
			ssb_printk(KERN_ERR PFX "Failed to thaw device %s\n",
				   dev->dev->bus_id);
		}
	}

	return 0;
}
#endif /* CONFIG_SSB_PCIHOST */

static void ssb_device_shutdown(struct device *dev)
{
	struct ssb_device *ssb_dev = dev_to_ssb_dev(dev);
	struct ssb_driver *ssb_drv;

	if (!dev->driver)
		return;
	ssb_drv = drv_to_ssb_drv(dev->driver);
	if (ssb_drv && ssb_drv->shutdown)
		ssb_drv->shutdown(ssb_dev);
}

static int ssb_device_remove(struct device *dev)
{
	struct ssb_device *ssb_dev = dev_to_ssb_dev(dev);
	struct ssb_driver *ssb_drv = drv_to_ssb_drv(dev->driver);

	if (ssb_drv && ssb_drv->remove)
		ssb_drv->remove(ssb_dev);
	ssb_device_put(ssb_dev);

	return 0;
}

static int ssb_device_probe(struct device *dev)
{
	struct ssb_device *ssb_dev = dev_to_ssb_dev(dev);
	struct ssb_driver *ssb_drv = drv_to_ssb_drv(dev->driver);
	int err = 0;

	ssb_device_get(ssb_dev);
	if (ssb_drv && ssb_drv->probe)
		err = ssb_drv->probe(ssb_dev, &ssb_dev->id);
	if (err)
		ssb_device_put(ssb_dev);

	return err;
}

static int ssb_match_devid(const struct ssb_device_id *tabid,
			   const struct ssb_device_id *devid)
{
	if ((tabid->vendor != devid->vendor) &&
	    tabid->vendor != SSB_ANY_VENDOR)
		return 0;
	if ((tabid->coreid != devid->coreid) &&
	    tabid->coreid != SSB_ANY_ID)
		return 0;
	if ((tabid->revision != devid->revision) &&
	    tabid->revision != SSB_ANY_REV)
		return 0;
	return 1;
}

static int ssb_bus_match(struct device *dev, struct device_driver *drv)
{
	struct ssb_device *ssb_dev = dev_to_ssb_dev(dev);
	struct ssb_driver *ssb_drv = drv_to_ssb_drv(drv);
	const struct ssb_device_id *id;

	for (id = ssb_drv->id_table;
	     id->vendor || id->coreid || id->revision;
	     id++) {
		if (ssb_match_devid(id, &ssb_dev->id))
			return 1; /* found */
	}

	return 0;
}

static int ssb_device_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	struct ssb_device *ssb_dev = dev_to_ssb_dev(dev);

	if (!dev)
		return -ENODEV;

	return add_uevent_var(env,
			     "MODALIAS=ssb:v%04Xid%04Xrev%02X",
			     ssb_dev->id.vendor, ssb_dev->id.coreid,
			     ssb_dev->id.revision);
}

static struct bus_type ssb_bustype = {
	.name		= "ssb",
	.match		= ssb_bus_match,
	.probe		= ssb_device_probe,
	.remove		= ssb_device_remove,
	.shutdown	= ssb_device_shutdown,
	.suspend	= ssb_device_suspend,
	.resume		= ssb_device_resume,
	.uevent		= ssb_device_uevent,
};

static void ssb_buses_lock(void)
{
	/* See the comment at the ssb_is_early_boot definition */
	if (!ssb_is_early_boot)
		mutex_lock(&buses_mutex);
}

static void ssb_buses_unlock(void)
{
	/* See the comment at the ssb_is_early_boot definition */
	if (!ssb_is_early_boot)
		mutex_unlock(&buses_mutex);
}

static void ssb_devices_unregister(struct ssb_bus *bus)
{
	struct ssb_device *sdev;
	int i;

	for (i = bus->nr_devices - 1; i >= 0; i--) {
		sdev = &(bus->devices[i]);
		if (sdev->dev)
			device_unregister(sdev->dev);
	}
}

void ssb_bus_unregister(struct ssb_bus *bus)
{
	ssb_buses_lock();
	ssb_devices_unregister(bus);
	list_del(&bus->list);
	ssb_buses_unlock();

	/* ssb_pcmcia_exit(bus); */
	ssb_pci_exit(bus);
	ssb_iounmap(bus);
}
EXPORT_SYMBOL(ssb_bus_unregister);

static void ssb_release_dev(struct device *dev)
{
	struct __ssb_dev_wrapper *devwrap;

	devwrap = container_of(dev, struct __ssb_dev_wrapper, dev);
	kfree(devwrap);
}

static int ssb_devices_register(struct ssb_bus *bus)
{
	struct ssb_device *sdev;
	struct device *dev;
	struct __ssb_dev_wrapper *devwrap;
	int i, err = 0;
	int dev_idx = 0;

	for (i = 0; i < bus->nr_devices; i++) {
		sdev = &(bus->devices[i]);

		/* We don't register SSB-system devices to the kernel,
		 * as the drivers for them are built into SSB. */
		switch (sdev->id.coreid) {
		case SSB_DEV_CHIPCOMMON:
		case SSB_DEV_PCI:
		case SSB_DEV_PCIE:
		case SSB_DEV_PCMCIA:
		case SSB_DEV_MIPS:
		case SSB_DEV_MIPS_3302:
		case SSB_DEV_EXTIF:
			continue;
		}

		devwrap = kzalloc(sizeof(*devwrap), GFP_KERNEL);
		if (!devwrap) {
			ssb_printk(KERN_ERR PFX
				   "Could not allocate device\n");
			err = -ENOMEM;
			goto error;
		}
		dev = &devwrap->dev;
		devwrap->sdev = sdev;

		dev->release = ssb_release_dev;
		dev->bus = &ssb_bustype;
		snprintf(dev->bus_id, sizeof(dev->bus_id),
			 "ssb%u:%d", bus->busnumber, dev_idx);

		switch (bus->bustype) {
		case SSB_BUSTYPE_PCI:
#ifdef CONFIG_SSB_PCIHOST
			sdev->irq = bus->host_pci->irq;
			dev->parent = &bus->host_pci->dev;
#endif
			break;
		case SSB_BUSTYPE_PCMCIA:
#ifdef CONFIG_SSB_PCMCIAHOST
			sdev->irq = bus->host_pcmcia->irq.AssignedIRQ;
			dev->parent = &bus->host_pcmcia->dev;
#endif
			break;
		case SSB_BUSTYPE_SSB:
			break;
		}

		sdev->dev = dev;
		err = device_register(dev);
		if (err) {
			ssb_printk(KERN_ERR PFX
				   "Could not register %s\n",
				   dev->bus_id);
			/* Set dev to NULL to not unregister
			 * dev on error unwinding. */
			sdev->dev = NULL;
			kfree(devwrap);
			goto error;
		}
		dev_idx++;
	}

	return 0;
error:
	/* Unwind the already registered devices. */
	ssb_devices_unregister(bus);
	return err;
}

/* Needs ssb_buses_lock() */
static int ssb_attach_queued_buses(void)
{
	struct ssb_bus *bus, *n;
	int err = 0;
	int drop_them_all = 0;

	list_for_each_entry_safe(bus, n, &attach_queue, list) {
		if (drop_them_all) {
			list_del(&bus->list);
			continue;
		}
		/* Can't init the PCIcore in ssb_bus_register(), as that
		 * is too early in boot for embedded systems
		 * (no udelay() available). So do it here in attach stage.
		 */
		err = ssb_bus_powerup(bus, 0);
		if (err)
			goto error;
		ssb_pcicore_init(&bus->pcicore);
		ssb_bus_may_powerdown(bus);

		err = ssb_devices_register(bus);
error:
		if (err) {
			drop_them_all = 1;
			list_del(&bus->list);
			continue;
		}
		list_move_tail(&bus->list, &buses);
	}

	return err;
}

static u16 ssb_ssb_read16(struct ssb_device *dev, u16 offset)
{
	struct ssb_bus *bus = dev->bus;

	offset += dev->core_index * SSB_CORE_SIZE;
	return readw(bus->mmio + offset);
}

static u32 ssb_ssb_read32(struct ssb_device *dev, u16 offset)
{
	struct ssb_bus *bus = dev->bus;

	offset += dev->core_index * SSB_CORE_SIZE;
	return readl(bus->mmio + offset);
}

static void ssb_ssb_write16(struct ssb_device *dev, u16 offset, u16 value)
{
	struct ssb_bus *bus = dev->bus;

	offset += dev->core_index * SSB_CORE_SIZE;
	writew(value, bus->mmio + offset);
}

static void ssb_ssb_write32(struct ssb_device *dev, u16 offset, u32 value)
{
	struct ssb_bus *bus = dev->bus;

	offset += dev->core_index * SSB_CORE_SIZE;
	writel(value, bus->mmio + offset);
}

/* Ops for the plain SSB bus without a host-device (no PCI or PCMCIA). */
static const struct ssb_bus_ops ssb_ssb_ops = {
	.read16		= ssb_ssb_read16,
	.read32		= ssb_ssb_read32,
	.write16	= ssb_ssb_write16,
	.write32	= ssb_ssb_write32,
};

static int ssb_fetch_invariants(struct ssb_bus *bus,
				ssb_invariants_func_t get_invariants)
{
	struct ssb_init_invariants iv;
	int err;

	memset(&iv, 0, sizeof(iv));
	err = get_invariants(bus, &iv);
	if (err)
		goto out;
	memcpy(&bus->boardinfo, &iv.boardinfo, sizeof(iv.boardinfo));
	memcpy(&bus->sprom, &iv.sprom, sizeof(iv.sprom));
out:
	return err;
}

static int ssb_bus_register(struct ssb_bus *bus,
			    ssb_invariants_func_t get_invariants,
			    unsigned long baseaddr)
{
	int err;

	spin_lock_init(&bus->bar_lock);
	INIT_LIST_HEAD(&bus->list);

	/* Powerup the bus */
	err = ssb_pci_xtal(bus, SSB_GPIO_XTAL | SSB_GPIO_PLL, 1);
	if (err)
		goto out;
	ssb_buses_lock();
	bus->busnumber = next_busnumber;
	/* Scan for devices (cores) */
	err = ssb_bus_scan(bus, baseaddr);
	if (err)