path: root/arch/s390/pci/pci.c

/*
 * Copyright IBM Corp. 2012
 *
 * Author(s):
 *   Jan Glauber <jang@linux.vnet.ibm.com>
 *
 * The System z PCI code is a rewrite from a prototype by
 * the following people (Kudoz!):
 *   Alexander Schmidt
 *   Christoph Raisch
 *   Hannes Hering
 *   Hoang-Nam Nguyen
 *   Jan-Bernd Themann
 *   Stefan Roscher
 *   Thomas Klein
 */

#define COMPONENT "zPCI"
#define pr_fmt(fmt) COMPONENT ": " fmt

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/delay.h>
#include <linux/irq.h>
#include <linux/kernel_stat.h>
#include <linux/seq_file.h>
#include <linux/pci.h>
#include <linux/msi.h>

#include <asm/isc.h>
#include <asm/airq.h>
#include <asm/facility.h>
#include <asm/pci_insn.h>
#include <asm/pci_clp.h>
#include <asm/pci_dma.h>

#define DEBUG				/* enable pr_debug */

#define	SIC_IRQ_MODE_ALL		0
#define	SIC_IRQ_MODE_SINGLE		1

#define ZPCI_NR_DMA_SPACES		1
#define ZPCI_MSI_VEC_BITS		6
#define ZPCI_NR_DEVICES			CONFIG_PCI_NR_FUNCTIONS

/* list of all detected zpci devices */
LIST_HEAD(zpci_list);
EXPORT_SYMBOL_GPL(zpci_list);
DEFINE_MUTEX(zpci_list_lock);
EXPORT_SYMBOL_GPL(zpci_list_lock);

static struct pci_hp_callback_ops *hotplug_ops;

static DECLARE_BITMAP(zpci_domain, ZPCI_NR_DEVICES);
static DEFINE_SPINLOCK(zpci_domain_lock);

struct callback {
	irq_handler_t	handler;
	void		*data;
};

struct zdev_irq_map {
	unsigned long	aibv;		/* AI bit vector */
	int		msi_vecs;	/* consecutive MSI-vectors used */
	int		__unused;
	struct callback	cb[ZPCI_NR_MSI_VECS]; /* callback handler array */
	spinlock_t	lock;		/* protect callbacks against de-reg */
};

struct intr_bucket {
	/* amap of adapters, one bit per dev, corresponds to one irq nr */
	unsigned long	*alloc;
	/* AI summary bit, global page for all devices */
	unsigned long	*aisb;
	/* pointer to aibv and callback data in zdev */
	struct zdev_irq_map *imap[ZPCI_NR_DEVICES];
	/* protects the whole bucket struct */
	spinlock_t	lock;
};

static struct intr_bucket *bucket;

/* Adapter local summary indicator */
static u8 *zpci_irq_si;

static atomic_t irq_retries = ATOMIC_INIT(0);

/* I/O Map */
static DEFINE_SPINLOCK(zpci_iomap_lock);
static DECLARE_BITMAP(zpci_iomap, ZPCI_IOMAP_MAX_ENTRIES);
struct zpci_iomap_entry *zpci_iomap_start;
EXPORT_SYMBOL_GPL(zpci_iomap_start);

/* highest irq summary bit */
static int __read_mostly aisb_max;

static struct kmem_cache *zdev_irq_cache;
static struct kmem_cache *zdev_fmb_cache;

static inline int irq_to_msi_nr(unsigned int irq)
{
	return irq & ZPCI_MSI_MASK;
}

static inline int irq_to_dev_nr(unsigned int irq)
{
	return irq >> ZPCI_MSI_VEC_BITS;
}

static inline struct zdev_irq_map *get_imap(unsigned int irq)
{
	return bucket->imap[irq_to_dev_nr(irq)];
}

struct zpci_dev *get_zdev(struct pci_dev *pdev)
{
	return (struct zpci_dev *) pdev->sysdata;
}

struct zpci_dev *get_zdev_by_fid(u32 fid)
{
	struct zpci_dev *tmp, *zdev = NULL;

	mutex_lock(&zpci_list_lock);
	list_for_each_entry(tmp, &zpci_list, entry) {
		if (tmp->fid == fid) {
			zdev = tmp;
			break;
		}
	}
	mutex_unlock(&zpci_list_lock);
	return zdev;
}

bool zpci_fid_present(u32 fid)
{
	return (get_zdev_by_fid(fid) != NULL) ? true : false;
}

static struct zpci_dev *get_zdev_by_bus(struct pci_bus *bus)
{
	return (bus && bus->sysdata) ? (struct zpci_dev *) bus->sysdata : NULL;
}

int pci_domain_nr(struct pci_bus *bus)
{
	return ((struct zpci_dev *) bus->sysdata)->domain;
}
EXPORT_SYMBOL_GPL(pci_domain_nr);

int pci_proc_domain(struct pci_bus *bus)
{
	return pci_domain_nr(bus);
}
EXPORT_SYMBOL_GPL(pci_proc_domain);

/* Modify PCI: Register adapter interruptions */
static int zpci_register_airq(struct zpci_dev *zdev, unsigned int aisb,
			      u64 aibv)
{
	u64 req = ZPCI_CREATE_REQ(zdev->