/* * 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 KMSG_COMPONENT "zpci" #define pr_fmt(fmt) KMSG_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_NR_DEVICES CONFIG_PCI_NR_FUNCTIONS /* list of all detected zpci devices */ static LIST_HEAD(zpci_list); static DEFINE_SPINLOCK(zpci_list_lock); static struct irq_chip zpci_irq_chip = { .name = "zPCI", .irq_unmask = pci_msi_unmask_irq, .irq_mask = pci_msi_mask_irq, }; static DECLARE_BITMAP(zpci_domain, ZPCI_NR_DEVICES); static DEFINE_SPINLOCK(zpci_domain_lock); static struct airq_iv *zpci_aisb_iv; static struct airq_iv *zpci_aibv[ZPCI_NR_DEVICES]; /* Adapter interrupt definitions */ static void zpci_irq_handler(struct airq_struct *airq); static struct airq_struct zpci_airq = { .handler = zpci_irq_handler, .isc = PCI_ISC, }; /* 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); static struct kmem_cache *zdev_fmb_cache; struct zpci_dev *get_zdev_by_fid(u32 fid) { struct zpci_dev *tmp, *zdev = NULL; spin_lock(&zpci_list_lock); list_for_each_entry(tmp, &zpci_list, entry) { if (tmp->fid == fid) { zdev = tmp; break; } } spin_unlock(&zpci_list_lock); return zdev; } 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_set_airq(struct zpci_dev *zdev) { u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT); struct zpci_fib fib = {0}; fib.isc = PCI_ISC; fib.sum = 1; /* enable summary notifications */ fib.noi = airq_iv_end(zdev->aibv); fib.aibv = (unsigned long) zdev->aibv->vector; fib.aibvo = 0; /* each zdev has its own interrupt vector */ fib.aisb = (unsigned long) zpci_aisb_iv->vector + (zdev->aisb/64)*8; fib.aisbo = zdev->aisb & 63; return zpci_mod_fc(req, &fib); } struct mod_pci_args { u64 base; u64 limit; u64 iota; u64 fmb_addr; }; static int mod_pci(struct zpci_dev *zdev, int fn, u8 dmaas, struct mod_pci_args *args) { u64 req = ZPCI_CREATE_REQ(zdev->fh, dmaas, fn); struct zpci_fib fib = {0}; fib.pba = args->base; fib.pal = args->limit; fib.iota = args->iota; fib.fmb_addr = args->fmb_addr; return zpci_mod_fc(req, &fib); } /* Modify PCI: Register I/O address translation parameters */ int zpci_register_ioat(struct zpci_dev *zdev, u8 dmaas, u64 base, u64 limit, u64 iota) { struct mod_pci_args args = { base, limit, iota, 0 }; WARN_ON_ONCE(iota & 0x3fff); args.iota |= ZPCI_IOTA_RTTO_FLAG; return mod_pci(zdev, ZPCI_MOD_FC_REG_IOAT, dmaas, &args); } /* Modify PCI: Unregister I/O address translation parameters */ int zpci_unregister_ioat(struct zpci_dev *zdev, u8 dmaas) { struct mod_pci_args args = { 0, 0, 0, 0 }; return mod_pci(zdev, ZPCI_MOD_FC_DEREG_IOAT, dmaas, &args); } /* Modify PCI: Unregister adapter interruptions */ static int zpci_clear_airq(struct zpci_dev *zdev) { struct mod_pci_args args = { 0, 0, 0, 0 }; return mod_pci(zdev, ZPCI_MOD_FC_DEREG_INT, 0, &args); } /* Modify PCI: Set PCI function measurement parameters */ int zpci_fmb_enable_device(struct zpci_dev *zdev) { struct mod_pci_args args = { 0, 0, 0, 0 }; if (zdev->fmb) return -EINVAL; zdev->fmb = kmem_cache_zalloc(zdev_fmb_cache, GFP_KERNEL); if (!zdev->fmb) return -ENOMEM; WARN_ON((u64) zdev->fmb & 0xf); /* reset software counters */ atomic64_set(&zdev->allocated_pages, 0); atomic64_set(&zdev->mapped_pages, 0); atomic64_set(&zdev->unmapped_pages, 0); args.fmb_addr = virt_to_phys(zdev->fmb); return mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args); } /* Modify PCI: Disable PCI function measurement */ int zpci_fmb_disable_device(struct zpci_dev *zdev) { struct mod_pci_args args = { 0, 0, 0, 0 }; int rc; if (!zdev->fmb) return -EINVAL; /* Function measurement is disabled if fmb address is zero */ rc = mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args); kmem_cache_free(zdev_fmb_cache, zdev->fmb); zdev->fmb = NULL; return rc; } #define ZPCI_PCIAS_CFGSPC 15 static int zpci_cfg_load(struct zpci_dev *zdev, int offset, u32 *val, u8 len) { u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len); u64 data; int rc; rc = zpci_load(&data, req, offset); if (!rc) { data = data << ((8 - len) * 8); data = le64_to_cpu(data); *val = (u32) data; } else *val = 0xffffffff; return rc; } static int zpci_cfg_store(struct zpci_dev *zdev, int offset, u32 val, u8 len) { u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len); u64 data = val; int rc; data = cpu_to_le64(data); data = data >> ((8 - len) * 8); rc = zpci_store(data, req, offset); return rc; } void pcibios_fixup_bus(struct pci_bus *bus) { } resource_size_t pcibios_align_resource(void *data, const struct resource *res, resource_size_t size, resource_size_t align) { return 0; } /* combine single writes by using store-block insn */ void __iowrite64_copy(void __iomem *to, const void *from, size_t count) { zpci_memcpy_toio(to, from, count); } /* Create a virtual mapping cookie for a PCI BAR */ void __iomem *pci_iomap_range(struct pci_dev *pdev, int bar, unsigned long offset, unsigned long max) { struct zpci_dev *zdev = to_zpci(pdev); u64 addr; int idx; if ((bar & 7) != bar) return NULL; idx = zdev->bars[bar].map_idx; spin_lock(&zpci_iomap_lock); if (zpci_iomap_start[idx].count++) { BUG_ON(zpci_iomap_start[idx].fh != zdev->fh || zpci_iomap_start[idx].bar != bar); } else { zpci_iomap_start[idx].fh = zdev->fh; zpci_iomap_start[idx].bar = bar; } /* Detect overrun */ BUG_ON(!zpci_iomap_start[idx].count); spin_unlock(&zpci_iomap_lock); addr = ZPCI_IOMAP_ADDR_BASE | ((u64) idx << 48); return (void __iomem *) addr + offset; } EXPORT_SYMBOL(pci_iomap_range); void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) { return pci_iomap_range(dev, bar, 0, maxlen); } EXPORT_SYMBOL(pci_iomap); void pci_iounmap(struct pci_dev *pdev, void __iomem *addr) { unsigned int idx; idx = (((__force u64) addr) & ~ZPCI_IOMAP_ADDR_BASE) >> 48; spin_lock(&zpci_iomap_lock); /* Detect underrun */ BUG_ON(!zpci_iomap_start[idx].count); if (!--zpci_iomap_start[idx].count) { zpci_iomap_start[idx].fh = 0; zpci_iomap_start[idx].bar = 0; } spin_unlock(&zpci_iomap_lock); } EXPORT_SYMBOL(pci_iounmap); static int pci_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *val) { struct zpci_dev *zdev = get_zdev_by_bus(bus); int ret; if (!zdev || devfn != ZPCI_DEVFN) ret = -ENODEV; else ret = zpci_cfg_load(zdev, where, val, size); return ret; } static int pci_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val) { struct zpci_dev *zdev = get_zdev_by_bus(bus); int ret; if (!zdev || devfn != ZPCI_DEVFN) ret = -ENODEV; else ret = zpci_cfg_store(zdev, where, val, size); return ret; } static struct pci_ops pci_root_ops = { .read = pci_read, .write = pci_write, }; static void zpci_irq_handler(struct airq_struct *airq) { unsigned long si, ai; struct airq_iv *aibv; int irqs_on = 0; inc_irq_stat(IRQIO_PCI); for (si = 0;;) { /* Scan adapter summary indicator bit vector */ si = airq_iv_scan(zpci_aisb_iv, si, airq_iv_end(zpci_aisb_iv)); if (si == -1UL) { if (irqs_on++) /* End of second scan with interrupts on. */ break; /* First scan complete, reenable interrupts. */ zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC); si = 0; continue; } /* Scan the adapter interrupt vector for this device. */ aibv = zpci_aibv[si]; for (ai = 0;;) { ai = airq_iv_scan(aibv, ai, airq_iv_end(aibv)); if (ai == -1UL) break; inc_irq_stat(IRQIO_MSI); airq_iv_lock(aibv, ai); generic_handle_irq(airq_iv_get_data(aibv, ai)); airq_iv_unlock(aibv, ai); } } } int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type) { struct zpci_dev *zdev = to_zpci(pdev); unsigned int hwirq, msi_vecs; unsigned long aisb; struct msi_desc *msi; struct msi_msg msg; int rc, irq; if (type == PCI_CAP_ID_MSI && nvec > 1) return 1; msi_vecs = min_t(unsigned int, nvec, zdev->max_msi); /* Allocate adapter summary indicator bit */ rc = -EIO; aisb = airq_iv_alloc_bit(zpci_aisb_iv); if (aisb == -1UL) goto out; zdev->aisb = aisb; /* Create adapter interrupt vector */ rc = -ENOMEM; zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK); if (!zdev->aibv) goto out_si; /* Wire up shortcut pointer */ zpci_aibv[aisb] = zdev->aibv; /* Request MSI interrupts */ hwirq = 0; for_each_pci_msi_entry(msi, pdev) { rc = -EIO; irq = irq_alloc_desc(0); /* Alloc irq on node 0 */ if (irq < 0) goto out_msi; rc = irq_set_msi_desc(irq, msi); if (rc) goto out_msi; irq_set_chip_and_handler(irq, &zpci_irq_chip, handle_simple_irq); msg.data = hwirq; msg.address_lo = zdev->msi_addr & 0xffffffff; msg.address_hi = zdev->msi_addr >> 32; pci_write_msi_msg(irq, &msg); airq_iv_set_data(zdev->aibv, hwirq, irq); hwirq++; } /* Enable adapter interrupts */ rc = zpci_set_airq(zdev); if (rc) goto out_msi; return (msi_vecs == nvec) ? 0 : msi_vecs; out_msi: for_each_pci_msi_entry(msi, pdev) { if (hwirq-- == 0) break; irq_set_msi_desc(msi->irq, NULL); irq_free_desc(msi->irq); msi->msg.address_lo = 0; msi->msg.address_hi = 0; msi->msg.data = 0; msi->irq = 0; } zpci_aibv[aisb] = NULL; airq_iv_release(zdev->aibv); out_si: airq_iv_free_bit(zpci_aisb_iv, aisb); out: return rc; } void arch_teardown_msi_irqs(struct pci_dev *pdev) { struct zpci_dev *zdev = to_zpci(pdev); struct msi_desc *msi; int rc; /* Disable adapter interrupts */ rc = zpci_clear_airq(zdev); if (rc) return; /* Release MSI interrupts */ for_each_pci_msi_entry(msi, pdev) { if (msi->msi_attrib.is_msix) __pci_msix_desc_mask_irq(msi, 1); else __pci_msi_desc_mask_irq(msi, 1, 1); irq_set_msi_desc(msi->irq, NULL); irq_free_desc(msi->irq); msi->msg.address_lo = 0; msi->msg.address_hi = 0; msi->msg.data = 0; msi->irq = 0; } zpci_aibv[zdev->aisb] = NULL; airq_iv_release(zdev->aibv); airq_iv_free_bit(zpci_aisb_iv, zdev->aisb); } static void zpci_map_resources(struct pci_dev *pdev) { resource_size_t len; int i; for (i = 0; i < PCI_BAR_COUNT; i++) { len = pci_resource_len(pdev, i); if (!len) continue; pdev->resource[i].start = (resource_size_t __force) pci_iomap(pdev, i, 0); pdev->resource[i].end = pdev->resource[i].start + len - 1; } } static void zpci_unmap_resources(struct pci_dev *pdev) { resource_size_t len; int i; for (i = 0; i < PCI_BAR_COUNT; i++) { len = pci_resource_len(pdev, i); if (!len) continue; pci_iounmap(pdev, (void __iomem __force *) pdev->resource[i].start); } } static int __init zpci_irq_init(void) { int rc; rc = register_adapter_interrupt(&zpci_airq); if (rc) goto out; /* Set summary to 1 to be called every time for the ISC. */ *zpci_airq.lsi_ptr = 1; rc = -ENOMEM; zpci_aisb_iv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC); if (!zpci_aisb_iv) goto out_airq; zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC); return 0; out_airq: unregister_adapter_interrupt(&zpci_airq); out: return rc; } static void zpci_irq_exit(void) { airq_iv_release(zpci_aisb_iv); unregister_adapter_interrupt(&zpci_airq); } static int zpci_alloc_iomap(struct zpci_dev *zdev) { int entry; spin_lock(&zpci_iomap_lock); entry = find_first_zero_bit(zpci_iomap, ZPCI_IOMAP_MAX_ENTRIES); if (entry == ZPCI_IOMAP_MAX_ENTRIES) { spin_unlock(&zpci_iomap_lock); return -ENOSPC; } set_bit(entry, zpci_iomap); spin_unlock(&zpci_iomap_lock); return entry; } static void zpci_free_iomap(struct zpci_dev *zdev, int entry) { spin_lock(&zpci_iomap_lock); memset(&zpci_iomap_start[entry], 0, sizeof(struct zpci_iomap_entry)); clear_bit(entry, zpci_iomap); spin_unlock(&zpci_iomap_lock); } static struct resource *__alloc_res(struct zpci_dev *zdev, unsigned long start, unsigned long size, unsigned long flags) { struct resource *r; r = kzalloc(sizeof(*r), GFP_KERNEL); if (!r) return NULL; r->start = start; r->end = r->start + size - 1; r->flags = flags; r->name = zdev->res_name; if (request_resource(&iomem_resource, r)) { kfree(r); return NULL; } return r; } static int zpci_setup_bus_resources(struct zpci_dev *zdev, struct list_head *resources) { unsigned long addr, size, flags; struct resource *res; int i, entry; snprintf(zdev->res_name, sizeof(zdev->res_name), "PCI Bus %04x:%02x", zdev->domain, ZPCI_BUS_NR); for (i = 0; i < PCI_BAR_COUNT; i++) { if (!zdev->bars[i].size) continue; entry = zpci_alloc_iomap(zdev); if (entry < 0) return entry; zdev->bars[i].map_idx = entry; /* only MMIO is supported */ flags = IORESOURCE_MEM; if (zdev->bars[i].val & 8) flags |= IORESOURCE_PREFETCH; if (zdev->bars[i].val & 4) flags |= IORESOURCE_MEM_64; addr = ZPCI_IOMAP_ADDR_BASE + ((u64) entry << 48); size = 1UL << zdev->bars[i].size; res = __alloc_res(zdev, addr, size, flags); if (!res) { zpci_free_iomap(zdev, entry); return -ENOMEM; } zdev->bars[i].res = res; pci_add_resource(resources, res); } return 0; } static void zpci_cleanup_bus_resources(struct zpci_dev *zdev) { int i; for (i = 0; i < PCI_BAR_COUNT; i++) { if (!zdev->bars[i].size || !zdev->bars[i].res) continue; zpci_free_iomap(zdev, zdev->bars[i].map_idx); release_resource(zdev->bars[i].res); kfree(zdev->bars[i].res); } } int pcibios_add_device(struct pci_dev *pdev) { struct zpci_dev *zdev = to_zpci(pdev); struct resource *res; int i; zdev->pdev = pdev; pdev->dev.groups = zpci_attr_groups; zpci_map_resources(pdev); for (i = 0; i < PCI_BAR_COUNT; i++) { res = &pdev->resource[i]; if (res->parent || !res->flags) continue; pci_claim_resource(pdev, i); } return 0; } void pcibios_release_device(struct pci_dev *pdev) { zpci_unmap_resources(pdev); } int pcibios_enable_device(struct pci_dev *pdev, int mask) { struct zpci_dev *zdev = to_zpci(pdev); zdev->pdev = pdev; zpci_debug_init_device(zdev); zpci_fmb_enable_device(zdev); return pci_enable_resources(pdev, mask); } void pcibios_disable_device(struct pci_dev *pdev) { struct zpci_dev *zdev = to_zpci(pdev); zpci_fmb_disable_device(zdev); zpci_debug_exit_device(zdev); zdev->pdev = NULL; } #ifdef CONFIG_HIBERNATE_CALLBACKS static int zpci_restore(struct device *dev) { struct pci_dev *pdev = to_pci_dev(dev); struct zpci_dev *zdev = to_zpci(pdev); int ret = 0; if (zdev->state != ZPCI_FN_STATE_ONLINE) goto out; ret = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES); if (ret) goto out; zpci_map_resources(pdev); zpci_register_ioat(zdev, 0, zdev->start_dma + PAGE_OFFSET, zdev->start_dma + zdev->iommu_size - 1, (u64) zdev->dma_table); out: return ret; } static int zpci_freeze(struct device *dev) { struct pci_dev *pdev = to_pci_dev(dev); struct zpci_dev *zdev = to_zpci(pdev); if (zdev->state != ZPCI_FN_STATE_ONLINE) return 0; zpci_unregister_ioat(zdev, 0); zpci_unmap_resources(pdev); return clp_disable_fh(zdev); } struct dev_pm_ops pcibios_pm_ops = { .thaw_noirq = zpci_restore, .freeze_noirq = zpci_freeze, .restore_noirq = zpci_restore, .poweroff_noirq = zpci_freeze, }; #endif /* CONFIG_HIBERNATE_CALLBACKS */ static int zpci_alloc_domain(struct zpci_dev *zdev) { spin_lock(&zpci_domain_lock); zdev->domain = find_first_zero_bit(zpci_domain, ZPCI_NR_DEVICES); if (zdev->domain == ZPCI_NR_DEVICES) { spin_unlock(&zpci_domain_lock); return -ENOSPC; } set_bit(zdev->domain, zpci_domain); spin_unlock(&zpci_domain_lock); return 0; } static void zpci_free_domain(struct zpci_dev *zdev) { spin_lock(&zpci_domain_lock); clear_bit(zdev->domain, zpci_domain); spin_unlock(&zpci_domain_lock); } void pcibios_remove_bus(struct pci_bus *bus) { struct zpci_dev *zdev = get_zdev_by_bus(bus); zpci_exit_slot(zdev); zpci_cleanup_bus_resources(zdev); zpci_free_domain(zdev); spin_lock(&zpci_list_lock); list_del(&zdev->entry); spin_unlock(&zpci_list_lock); kfree(zdev); } static int zpci_scan_bus(struct zpci_dev *zdev) { LIST_HEAD(resources); int ret; ret = zpci_setup_bus_resources(zdev, &resources); if (ret) goto error; zdev->bus = pci_scan_root_bus(NULL, ZPCI_BUS_NR, &pci_root_ops, zdev, &resources); if (!zdev->bus) { ret = -EIO; goto error; } zdev->bus->max_bus_speed = zdev->max_bus_speed; pci_bus_add_devices(zdev->bus); return 0; error: zpci_cleanup_bus_resources(zdev); pci_free_resource_list(&resources); return ret; } int zpci_enable_device(struct zpci_dev *zdev) { int rc; rc = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES); if (rc) goto out; rc = zpci_dma_init_device(zdev); if (rc) goto out_dma; zdev->state = ZPCI_FN_STATE_ONLINE; return 0; out_dma: clp_disable_fh(zdev); out: return rc; } EXPORT_SYMBOL_GPL(zpci_enable_device); int zpci_disable_device(struct zpci_dev *zdev) { zpci_dma_exit_device(zdev); return clp_disable_fh(zdev); } EXPORT_SYMBOL_GPL(zpci_disable_device); int zpci_create_device(struct zpci_dev *zdev) { int rc; rc = zpci_alloc_domain(zdev); if (rc) goto out; mutex_init(&zdev->lock); if (zdev->state == ZPCI_FN_STATE_CONFIGURED) { rc = zpci_enable_device(zdev); if (rc) goto out_free; } rc = zpci_scan_bus(zdev); if (rc) goto out_disable; spin_lock(&zpci_list_lock); list_add_tail(&zdev->entry, &zpci_list); spin_unlock(&zpci_list_lock); zpci_init_slot(zdev); return 0; out_disable: if (zdev->state == ZPCI_FN_STATE_ONLINE) zpci_disable_device(zdev); out_free: zpci_free_domain(zdev); out: return rc; } void zpci_stop_device(struct zpci_dev *zdev) { zpci_dma_exit_device(zdev); /* * Note: SCLP disables fh via set-pci-fn so don't * do that here. */ } EXPORT_SYMBOL_GPL(zpci_stop_device); static inline int barsize(u8 size) { return (size) ? (1 << size) >> 10 : 0; } static int zpci_mem_init(void) { zdev_fmb_cache = kmem_cache_create("PCI_FMB_cache", sizeof(struct zpci_fmb), 16, 0, NULL); if (!zdev_fmb_cache) goto error_zdev; /* TODO: use realloc */ zpci_iomap_start = kzalloc(ZPCI_IOMAP_MAX_ENTRIES * sizeof(*zpci_iomap_start), GFP_KERNEL); if (!zpci_iomap_start) goto error_iomap; return 0; error_iomap: kmem_cache_destroy(zdev_fmb_cache); error_zdev: return -ENOMEM; } static void zpci_mem_exit(void) { kfree(zpci_iomap_start); kmem_cache_destroy(zdev_fmb_cache); } static unsigned int s390_pci_probe = 1; static unsigned int s390_pci_initialized; char * __init pcibios_setup(char *str) { if (!strcmp(str, "off")) { s390_pci_probe = 0; return NULL; } return str; } bool zpci_is_enabled(void) { return s390_pci_initialized; } static int __init pci_base_init(void) { int rc; if (!s390_pci_probe) return 0; if (!test_facility(69) || !test_facility(71) || !test_facility(72)) return 0; rc = zpci_debug_init(); if (rc) goto out; rc = zpci_mem_init(); if (rc) goto out_mem; rc = zpci_irq_init(); if (rc) goto out_irq; rc = zpci_dma_init(); if (rc) goto out_dma; rc = clp_scan_pci_devices(); if (rc) goto out_find; s390_pci_initialized = 1; return 0; out_find: zpci_dma_exit(); out_dma: zpci_irq_exit(); out_irq: zpci_mem_exit(); out_mem: zpci_debug_exit(); out: return rc; } subsys_initcall_sync(pci_base_init); void zpci_rescan(void) { if (zpci_is_enabled()) clp_rescan_pci_devices_simple(); }