/* * $Id: pci.c,v 1.91 1999/01/21 13:34:01 davem Exp $ * * PCI Bus Services, see include/linux/pci.h for further explanation. * * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter, * David Mosberger-Tang * * Copyright 1997 -- 2000 Martin Mares */ #include #include #include #include #include #include #include /* isa_dma_bridge_buggy */ /** * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children * @bus: pointer to PCI bus structure to search * * Given a PCI bus, returns the highest PCI bus number present in the set * including the given PCI bus and its list of child PCI buses. */ unsigned char __devinit pci_bus_max_busnr(struct pci_bus* bus) { struct list_head *tmp; unsigned char max, n; max = bus->number; list_for_each(tmp, &bus->children) { n = pci_bus_max_busnr(pci_bus_b(tmp)); if(n > max) max = n; } return max; } /** * pci_max_busnr - returns maximum PCI bus number * * Returns the highest PCI bus number present in the system global list of * PCI buses. */ unsigned char __devinit pci_max_busnr(void) { struct pci_bus *bus = NULL; unsigned char max, n; max = 0; while ((bus = pci_find_next_bus(bus)) != NULL) { n = pci_bus_max_busnr(bus); if(n > max) max = n; } return max; } static int __pci_bus_find_cap(struct pci_bus *bus, unsigned int devfn, u8 hdr_type, int cap) { u16 status; u8 pos, id; int ttl = 48; pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status); if (!(status & PCI_STATUS_CAP_LIST)) return 0; switch (hdr_type) { case PCI_HEADER_TYPE_NORMAL: case PCI_HEADER_TYPE_BRIDGE: pci_bus_read_config_byte(bus, devfn, PCI_CAPABILITY_LIST, &pos); break; case PCI_HEADER_TYPE_CARDBUS: pci_bus_read_config_byte(bus, devfn, PCI_CB_CAPABILITY_LIST, &pos); break; default: return 0; } while (ttl-- && pos >= 0x40) { pos &= ~3; pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID, &id); if (id == 0xff) break; if (id == cap) return pos; pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_NEXT, &pos); } return 0; } /** * pci_find_capability - query for devices' capabilities * @dev: PCI device to query * @cap: capability code * * Tell if a device supports a given PCI capability. * Returns the address of the requested capability structure within the * device's PCI configuration space or 0 in case the device does not * support it. Possible values for @cap: * * %PCI_CAP_ID_PM Power Management * %PCI_CAP_ID_AGP Accelerated Graphics Port * %PCI_CAP_ID_VPD Vital Product Data * %PCI_CAP_ID_SLOTID Slot Identification * %PCI_CAP_ID_MSI Message Signalled Interrupts * %PCI_CAP_ID_CHSWP CompactPCI HotSwap * %PCI_CAP_ID_PCIX PCI-X * %PCI_CAP_ID_EXP PCI Express */ int pci_find_capability(struct pci_dev *dev, int cap) { return __pci_bus_find_cap(dev->bus, dev->devfn, dev->hdr_type, cap); } /** * pci_bus_find_capability - query for devices' capabilities * @bus: the PCI bus to query * @devfn: PCI device to query * @cap: capability code * * Like pci_find_capability() but works for pci devices that do not have a * pci_dev structure set up yet. * * Returns the address of the requested capability structure within the * device's PCI configuration space or 0 in case the device does not * support it. */ int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap) { u8 hdr_type; pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type); return __pci_bus_find_cap(bus, devfn, hdr_type & 0x7f, cap); } /** * pci_find_ext_capability - Find an extended capability * @dev: PCI device to query * @cap: capability code * * Returns the address of the requested extended capability structure * within the device's PCI configuration space or 0 if the device does * not support it. Possible values for @cap: * * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting * %PCI_EXT_CAP_ID_VC Virtual Channel * %PCI_EXT_CAP_ID_DSN Device Serial Number * %PCI_EXT_CAP_ID_PWR Power Budgeting */ int pci_find_ext_capability(struct pci_dev *dev, int cap) { u32 header; int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */ int pos = 0x100; if (dev->cfg_size <= 256) return 0; if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL) return 0; /* * If we have no capabilities, this is indicated by cap ID, * cap version and next pointer all being 0. */ if (header == 0) return 0; while (ttl-- > 0) { if (PCI_EXT_CAP_ID(header) == cap) return pos; pos = PCI_EXT_CAP_NEXT(header); if (pos < 0x100) break; if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL) break; } return 0; } /** * pci_find_parent_resource - return resource region of parent bus of given region * @dev: PCI device structure contains resources to be searched * @res: child resource record for which parent is sought * * For given resource region of given device, return the resource * region of parent bus the given region is contained in or where * it should be allocated from. */ struct resource * pci_find_parent_resource(const struct pci_dev *dev, struct resource *res) { const struct pci_bus *bus = dev->bus; int i; struct resource *best = NULL; for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) { struct resource *r = bus->resource[i]; if (!r) continue; if (res->start && !(res->start >= r->start && res->end <= r->end)) continue; /* Not contained */ if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM)) continue; /* Wrong type */ if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH)) return r; /* Exact match */ if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH)) best = r; /* Approximating prefetchable by non-prefetchable */ } return best; } /** * pci_set_power_state - Set the power state of a PCI device * @dev: PCI device to be suspended * @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering * * Transition a device to a new power state, using the Power Management * Capabilities in the device's config space. * * RETURN VALUE: * -EINVAL if trying to enter a lower state than we're already in. * 0 if we're already in the requested state. * -EIO if device does not support PCI PM. * 0 if we can successfully change the power state. */ int pci_set_power_state(struct pci_dev *dev, pci_power_t state) { int pm; u16 pmcsr, pmc; /* bound the state we're entering */ if (state > PCI_D3hot) state = PCI_D3hot; /* Validate current state: * Can enter D0 from any state, but if we can only go deeper * to sleep if we're already in a low power state */ if (state != PCI_D0 && dev->current_state > state) return -EINVAL; else if (dev->current_state == state) return 0; /* we're already there */ /* find PCI PM capability in list */ pm = pci_find_capability(dev, PCI_CAP_ID_PM); /* abort if the device doesn't support PM capabilities */ if (!pm) return -EIO; pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc); if ((pmc & PCI_PM_CAP_VER_MASK) > 2) { printk(KERN_DEBUG "PCI: %s has unsupported PM cap regs version (%u)\n", pci_name(dev), pmc & PCI_PM_CAP_VER_MASK); return -EIO; } /* check if this device supports the desired state */ if (state == PCI_D1 || state == PCI_D2) { if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1)) return -EIO; else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2)) return -EIO; } /* If we're in D3, force entire word to 0. * This doesn't affect PME_Status, disables PME_En, and * sets PowerState to 0. */ if (dev->current_state >= PCI_D3hot) pmcsr = 0; else { pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr); pmcsr &= ~PCI_PM_CTRL_STATE_MASK; pmcsr |= state; } /* enter specified state */ pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr); /* Mandatory power management transition delays */ /* see PCI PM 1.1 5.6.1 table 18 */ if (state == PCI_D3hot || dev->current_state == PCI_D3hot) msleep(10); else if (state == PCI_D2 || dev->current_state == PCI_D2) udelay(200); dev->current_state = state; return 0; } /** * pci_choose_state - Choose the power state of a PCI device * @dev: PCI device to be suspended * @state: target sleep state for the whole system. This is the value * that is passed to suspend() function. * * Returns PCI power state suitable for given device and given system * message. */ pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state) { if (!pci_find_capability(dev, PCI_CAP_ID_PM)) return PCI_D0; switch (state) { case 0: return PCI_D0; case 3: return PCI_D3hot; default: printk("They asked me for state %d\n", state); BUG(); } return PCI_D0; } EXPORT_SYMBOL(pci_choose_state); /** * pci_save_state - save the PCI configuration space of a device before suspending * @dev: - PCI device that we're dealing with * @buffer: - buffer to hold config space context * * @buffer must be large enough to hold the entire PCI 2.2 config space * (>= 64 bytes). */ int pci_save_state(struct pci_dev *dev) { int i; /* XXX: 100% dword access ok here? */ for (i = 0; i < 16; i++) pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]); return 0; } /** * pci_restore_state - Restore the saved state of a PCI device * @dev: - PCI device that we're dealing with * @buffer: - saved PCI config space * */ int pci_restore_state(struct pci_dev *dev) { int i; for (i = 0; i < 16; i++) pci_write_config_dword(dev,i * 4, dev->saved_config_space[i]); return 0; } /** * pci_enable_device_bars - Initialize some of a device for use * @dev: PCI device to be initialized * @bars: bitmask of BAR's that must be configured * * Initialize device before it's used by a driver. Ask low-level code * to enable selected I/O and memory resources. Wake up the device if it * was suspended. Beware, this function can fail. */ int pci_enable_device_bars(struct pci_dev *dev, int bars) { int err; pci_set_power_state(dev, PCI_D0); if ((err = pcibios_enable_device(dev, bars)) < 0) return err; return 0; } /** * pci_enable_device - Initialize device before it's used by a driver. * @dev: PCI device to be initialized * * Initialize device before it's used by a driver. Ask low-level code * to enable I/O and memory. Wake up the device if it was suspended. * Beware, this function can fail. */ int pci_enable_device(struct pci_dev *dev) { int err; if ((err = pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1))) return err; pci_fixup_device(pci_fixup_enable, dev); dev->is_enabled = 1; return 0; } /** * pcibios_disable_device - disable arch specific PCI resources for device dev * @dev: the PCI device to disable * * Disables architecture specific PCI resources for the device. This * is the default implementation. Architecture implementations can * override this. */ void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {} /** * pci_disable_device - Disable PCI device after use * @dev: PCI device to be disabled * * Signal to the system that the PCI device is not in use by the system * anymore. This only involves disabling PCI bus-mastering, if active. */ void pci_disable_device(struct pci_dev *dev) { u16 pci_command; pci_read_config_word(dev, PCI_COMMAND, &pci_command); if (pci_command & PCI_COMMAND_MASTER) { pci_command &= ~PCI_COMMAND_MASTER; pci_write_config_word(dev, PCI_COMMAND, pci_command); } dev->is_busmaster = 0; pcibios_disable_device(dev); dev->is_enabled = 0; } /** * pci_enable_wake - enable device to generate PME# when suspended * @dev: - PCI device to operate on * @state: - Current state of device. * @enable: - Flag to enable or disable generation * * Set the bits in the device's PM Capabilities to generate PME# when * the system is suspended. * * -EIO is returned if device doesn't have PM Capabilities. * -EINVAL is returned if device supports it, but can't generate wake events. * 0 if operation is successful. * */ int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable) { int pm; u16 value; /* find PCI PM capability in list */ pm = pci_find_capability(dev, PCI_CAP_ID_PM); /* If device doesn't support PM Capabilities, but request is to disable * wake events, it's a nop; otherwise fail */ if (!pm) return enable ? -EIO : 0; /* Check device's ability to generate PME# */ pci_read_config_word(dev,pm+PCI_PM_PMC,&value); value &= PCI_PM_CAP_PME_MASK; value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */ /* Check if it can generate PME# from requested state. */ if (!value || !(value & (1 << state))) return enable ? -EINVAL : 0; pci_read_config_word(dev, pm + PCI_PM_CTRL, &value); /* Clear PME_Status by writing 1 to it and enable PME# */ value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE; if (!enable) value &= ~PCI_PM_CTRL_PME_ENABLE; pci_write_config_word(dev, pm + PCI_PM_CTRL, value); return 0; } int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge) { u8 pin; pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin); if (!pin) return -1; pin--; while (dev->bus->self) { pin = (pin + PCI_SLOT(dev->devfn)) % 4; dev = dev->bus->self; } *bridge = dev; return pin; } /** * pci_release_region - Release a PCI bar * @pdev: PCI device whose resources were previously reserved by pci_request_region * @bar: BAR to release * * Releases the PCI I/O and memory resources previously reserved by a * successful call to pci_request_region. Call this function only * after all use of the PCI regions has ceased. */ void pci_release_region(struct pci_dev *pdev, int bar) { if (pci_resource_len(pdev, bar) == 0) return; if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) release_region(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar)); else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) release_mem_region(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar)); } /** * pci_request_region - Reserved PCI I/O and memory resource * @pdev: PCI device whose resources are to be reserved * @bar: BAR to be reserved * @res_name: Name to be associated with resource. * * Mark the PCI region associated with PCI device @pdev BR @bar as * being reserved by owner @res_name. Do not access any * address inside the PCI regions unless this call returns * successfully. * * Returns 0 on success, or %EBUSY on error. A warning * message is also printed on failure. */ int pci_request_region(struct pci_dev *pdev, int bar, char *res_name) { if (pci_resource_len(pdev, bar) == 0) return 0; if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) { if (!request_region(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar), res_name)) goto err_out; } else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) { if (!request_mem_region(pci_resource_start(pdev, bar), pci_resource_len(pdev, bar), res_name)) goto err_out; } return 0; err_out: printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%lx@%lx for device %s\n", pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem", bar + 1, /* PCI BAR # */ pci_resource_len(pdev, bar), pci_resource_start(pdev, bar), pci_name(pdev)); return -EBUSY; } /** * pci_release_regions - Release reserved PCI I/O and memory resources * @pdev: PCI device whose resources were previously reserved by pci_request_regions * * Releases all PCI I/O and memory resources previously reserved by a * successful call to pci_request_regions. Call this function only * after all use of the PCI regions has ceased. */ void pci_release_regions(struct pci_dev *pdev) { int i; for (i = 0; i < 6; i++) pci_release_region(pdev, i); } /** * pci_request_regions - Reserved PCI I/O and memory resources * @pdev: PCI device whose resources are to be reserved * @res_name: Name to be associated with resource. * * Mark all PCI regions associated with PCI device @pdev as * being reserved by owner @res_name. Do not access any * address inside the PCI regions unless this call returns * successfully. * * Returns 0 on success, or %EBUSY on error. A warning * message is also printed on failure. */ int pci_request_regions(struct pci_dev *pdev, char *res_name) { int i; for (i = 0; i < 6; i++) if(pci_request_region(pdev, i, res_name)) goto err_out; return 0; err_out: while(--i >= 0) pci_release_region(pdev, i); return -EBUSY; } /** * pci_set_master - enables bus-mastering for device dev * @dev: the PCI device to enable * * Enables bus-mastering on the device and calls pcibios_set_master() * to do the needed arch specific settings. */ void pci_set_master(struct pci_dev *dev) { u16 cmd; pci_read_config_word(dev, PCI_COMMAND, &cmd); if (! (cmd & PCI_COMMAND_MASTER)) { pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev)); cmd |= PCI_COMMAND_MASTER; pci_write_config_word(dev, PCI_COMMAND, cmd); } dev->is_busmaster = 1; pcibios_set_master(dev); } #ifndef HAVE_ARCH_PCI_MWI /* This can be overridden by arch code. */ u8 pci_cache_line_size = L1_CACHE_BYTES >> 2; /** * pci_generic_prep_mwi - helper function for pci_set_mwi * @dev: the PCI device for which MWI is enabled * * Helper function for generic implementation of pcibios_prep_mwi * function. Originally copied from drivers/net/acenic.c. * Copyright 1998-2001 by Jes Sorensen, . * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ static int pci_generic_prep_mwi(struct pci_dev *dev) { u8 cacheline_size; if (!pci_cache_line_size) return -EINVAL; /* The system doesn't support MWI. */ /* Validate current setting: the PCI_CACHE_LINE_SIZE must be equal to or multiple of the right value. */ pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size); if (cacheline_size >= pci_cache_line_size && (cacheline_size % pci_cache_line_size) == 0) return 0; /* Write the correct value. */ pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size); /* Read it back. */ pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size); if (cacheline_size == pci_cache_line_size) return 0; printk(KERN_DEBUG "PCI: cache line size of %d is not supported " "by device %s\n", pci_cache_line_size << 2, pci_name(dev)); return -EINVAL; } #endif /* !HAVE_ARCH_PCI_MWI */ /** * pci_set_mwi - enables memory-write-invalidate PCI transaction * @dev: the PCI device for which MWI is enabled * * Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND, * and then calls @pcibios_set_mwi to do the needed arch specific * operations or a generic mwi-prep function. * * RETURNS: An appropriate -ERRNO error value on error, or zero for success. */ int pci_set_mwi(struct pci_dev *dev) { int rc; u16 cmd; #ifdef HAVE_ARCH_PCI_MWI rc = pcibios_prep_mwi(dev); #else rc = pci_generic_prep_mwi(dev); #endif if (rc) return rc; pci_read_config_word(dev, PCI_COMMAND, &cmd); if (! (cmd & PCI_COMMAND_INVALIDATE)) { pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n", pci_name(dev)); cmd |= PCI_COMMAND_INVALIDATE; pci_write_config_word(dev, PCI_COMMAND, cmd); } return 0; } /** * pci_clear_mwi - disables Memory-Write-Invalidate for device dev * @dev: the PCI device to disable * * Disables PCI Memory-Write-Invalidate transaction on the device */ void pci_clear_mwi(struct pci_dev *dev) { u16 cmd; pci_read_config_word(dev, PCI_COMMAND, &cmd); if (cmd & PCI_COMMAND_INVALIDATE) { cmd &= ~PCI_COMMAND_INVALIDATE; pci_write_config_word(dev, PCI_COMMAND, cmd); } } #ifndef HAVE_ARCH_PCI_SET_DMA_MASK /* * These can be overridden by arch-specific implementations */ int pci_set_dma_mask(struct pci_dev *dev, u64 mask) { if (!pci_dma_supported(dev, mask)) return -EIO; dev->dma_mask = mask; return 0; } int pci_dac_set_dma_mask(struct pci_dev *dev, u64 mask) { if (!pci_dac_dma_supported(dev, mask)) return -EIO; dev->dma_mask = mask; return 0; } int pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask) { if (!pci_dma_supported(dev, mask)) return -EIO; dev->dev.coherent_dma_mask = mask; return 0; } #endif static int __devinit pci_init(void) { struct pci_dev *dev = NULL; while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { pci_fixup_device(pci_fixup_final, dev); } return 0; } static int __devinit pci_setup(char *str) { while (str) { char *k = strchr(str, ','); if (k) *k++ = 0; if (*str && (str = pcibios_setup(str)) && *str) { /* PCI layer options should be handled here */ printk(KERN_ERR "PCI: Unknown option `%s'\n", str); } str = k; } return 1; } device_initcall(pci_init); __setup("pci=", pci_setup); #if defined(CONFIG_ISA) || defined(CONFIG_EISA) /* FIXME: Some boxes have multiple ISA bridges! */ struct pci_dev *isa_bridge; EXPORT_SYMBOL(isa_bridge); #endif EXPORT_SYMBOL(pci_enable_device_bars); EXPORT_SYMBOL(pci_enable_device); EXPORT_SYMBOL(pci_disable_device); EXPORT_SYMBOL(pci_max_busnr); EXPORT_SYMBOL(pci_bus_max_busnr); EXPORT_SYMBOL(pci_find_capability); EXPORT_SYMBOL(pci_bus_find_capability); EXPORT_SYMBOL(pci_release_regions); EXPORT_SYMBOL(pci_request_regions); EXPORT_SYMBOL(pci_release_region); EXPORT_SYMBOL(pci_request_region); EXPORT_SYMBOL(pci_set_master); EXPORT_SYMBOL(pci_set_mwi); EXPORT_SYMBOL(pci_clear_mwi); EXPORT_SYMBOL(pci_set_dma_mask); EXPORT_SYMBOL(pci_dac_set_dma_mask); EXPORT_SYMBOL(pci_set_consistent_dma_mask); EXPORT_SYMBOL(pci_assign_resource); EXPORT_SYMBOL(pci_find_parent_resource); EXPORT_SYMBOL(pci_set_power_state); EXPORT_SYMBOL(pci_save_state); EXPORT_SYMBOL(pci_restore_state); EXPORT_SYMBOL(pci_enable_wake); /* Quirk info */ EXPORT_SYMBOL(isa_dma_bridge_buggy); EXPORT_SYMBOL(pci_pci_problems);