/* * PCI Bus Services, see include/linux/pci.h for further explanation. * * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter, * David Mosberger-Tang * * Copyright 1997 -- 1999 Martin Mares * * Copyright 2003 -- Eric Biederman */ #include #include #include #include #include #include #include #include #include #include /** Given a device and register, read the size of the BAR for that register. * @param dev Pointer to the device structure * @param resource Pointer to the resource structure * @param index Address of the pci configuration register */ static void pci_get_resource(struct device *dev, struct resource *resource, unsigned long index) { uint32_t addr, size, base; unsigned long type; /* Initialize the resources to nothing */ resource->base = 0; resource->size = 0; resource->align = 0; resource->gran = 0; resource->limit = 0; resource->flags = 0; resource->index = index; addr = pci_read_config32(dev, index); /* FIXME: more consideration for 64-bit PCI devices, * we currently detect their size but otherwise * treat them as 32-bit resources */ /* get the size */ pci_write_config32(dev, index, ~0); size = pci_read_config32(dev, index); /* get the minimum value the bar can be set to */ pci_write_config32(dev, index, 0); base = pci_read_config32(dev, index); /* restore addr */ pci_write_config32(dev, index, addr); /* * some broken hardware has read-only registers that do not * really size correctly. You can tell this if addr == size * Example: the acer m7229 has BARs 1-4 normally read-only. * so BAR1 at offset 0x10 reads 0x1f1. If you size that register * by writing 0xffffffff to it, it will read back as 0x1f1 -- a * violation of the spec. * We catch this case and ignore it by settting size and type to 0. * This incidentally catches the common case where registers * read back as 0 for both address and size. */ if ((addr == size) && (addr == base)) { if (size != 0) { printk_debug( "%s register %02x(%08x), read-only ignoring it\n", dev_path(dev), index, addr); } resource->flags = 0; } /* Now compute the actual size, See PCI Spec 6.2.5.1 ... */ else if (size & PCI_BASE_ADDRESS_SPACE_IO) { type = size & (~PCI_BASE_ADDRESS_IO_MASK); /* BUG! Top 16 bits can be zero (or not) * So set them to 0xffff so they go away ... */ resource->size = (~((size | 0xffff0000) & PCI_BASE_ADDRESS_IO_MASK)) +1; resource->align = log2(resource->size); resource->gran = resource->align; resource->flags = IORESOURCE_IO; resource->limit = 0xffff; } else { /* A Memory mapped base address */ type = size & (~PCI_BASE_ADDRESS_MEM_MASK); resource->size = (~(size &PCI_BASE_ADDRESS_MEM_MASK)) +1; resource->align = log2(resource->size); resource->gran = resource->align; resource->flags = IORESOURCE_MEM; if (type & PCI_BASE_ADDRESS_MEM_PREFETCH) { resource->flags |= IORESOURCE_PREFETCH; } type &= PCI_BASE_ADDRESS_MEM_TYPE_MASK; if (type == PCI_BASE_ADDRESS_MEM_TYPE_32) { /* 32bit limit */ resource->limit = 0xffffffffUL; } else if (type == PCI_BASE_ADDRESS_MEM_TYPE_1M) { /* 1MB limit */ resource->limit = 0x000fffffUL; } else if (type == PCI_BASE_ADDRESS_MEM_TYPE_64) { unsigned long index_hi; /* 64bit limit * For now just treat this as a 32bit limit */ index_hi = index + 4; resource->limit = 0xffffffffUL; resource->flags |= IORESOURCE_PCI64; addr = pci_read_config32( dev, index_hi); /* get the extended size */ pci_write_config32(dev, index_hi, 0xffffffffUL); size = pci_read_config32( dev, index_hi); /* get the minimum value the bar can be set to */ pci_write_config32(dev, index_hi, 0); base = pci_read_config32(dev, index_hi); /* restore addr */ pci_write_config32(dev, index_hi, addr); if ((size == 0xffffffff) && (base == 0)) { /* Clear the top half of the bar */ pci_write_config32(dev, index_hi, 0); } else { printk_err("%s Unable to handle 64-bit address\n", dev_path(dev)); resource->flags = IORESOURCE_PCI64; } } else { /* Invalid value */ resource->flags = 0; } } /* dev->size holds the flags... */ return; } /** Read the base address registers for a given device. * @param dev Pointer to the dev structure * @param howmany How many registers to read (6 for device, 2 for bridge) */ static void pci_read_bases(struct device *dev, unsigned int howmany) { unsigned int reg; unsigned long index; reg = dev->resources; for(index = PCI_BASE_ADDRESS_0; (reg < MAX_RESOURCES) && (index < PCI_BASE_ADDRESS_0 + (howmany << 2)); ) { struct resource *resource; resource = &dev->resource[reg]; pci_get_resource(dev, resource, index); reg += (resource->flags & (IORESOURCE_IO | IORESOURCE_MEM))? 1:0; index += (resource->flags & IORESOURCE_PCI64)?8:4; } dev->resources = reg; } static void pci_bridge_read_bases(struct device *dev) { unsigned int reg = dev->resources; /* FIXME handle bridges without some of the optional resources */ /* Initialize the io space constraints on the current bus */ dev->resource[reg].base = 0; dev->resource[reg].size = 0; dev->resource[reg].align = log2(PCI_IO_BRIDGE_ALIGN); dev->resource[reg].gran = log2(PCI_IO_BRIDGE_ALIGN); dev->resource[reg].limit = 0xffffUL; dev->resource[reg].flags = IORESOURCE_IO | IORESOURCE_PCI_BRIDGE; dev->resource[reg].index = PCI_IO_BASE; compute_allocate_resource(&dev->link[0], &dev->resource[reg], IORESOURCE_IO, IORESOURCE_IO); reg++; /* Initiliaze the prefetchable memory constraints on the current bus */ dev->resource[reg].base = 0; dev->resource[reg].size = 0; dev->resource[reg].align = log2(PCI_MEM_BRIDGE_ALIGN); dev->resource[reg].gran = log2(PCI_MEM_BRIDGE_ALIGN); dev->resource[reg].limit = 0xffffffffUL; dev->resource[reg].flags = IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_PCI_BRIDGE; dev->resource[reg].index = PCI_PREF_MEMORY_BASE; compute_allocate_resource(&dev->link[0], &dev->resource[reg], IORESOURCE_MEM | IORESOURCE_PREFETCH, IORESOURCE_MEM | IORESOURCE_PREFETCH); reg++; /* Initialize the memory resources on the current bus */ dev->resource[reg].base = 0; dev->resource[reg].size = 0; dev->resource[reg].align = log2(PCI_MEM_BRIDGE_ALIGN); dev->resource[reg].gran = log2(PCI_MEM_BRIDGE_ALIGN); dev->resource[reg].limit = 0xffffffffUL; dev->resource[reg].flags = IORESOURCE_MEM | IORESOURCE_PCI_BRIDGE; dev->resource[reg].index = PCI_MEMORY_BASE; compute_allocate_resource(&dev->link[0], &dev->resource[reg], IORESOURCE_MEM | IORESOURCE_PREFETCH, IORESOURCE_MEM); reg++; dev->resources = reg; } void pci_dev_read_resources(struct device *dev) { uint32_t addr; dev->resources = 0; memset(&dev->resource[0], 0, sizeof(dev->resource)); pci_read_bases(dev, 6); addr = pci_read_config32(dev, PCI_ROM_ADDRESS); dev->rom_address = (addr == 0xffffffff)? 0 : addr; } void pci_bus_read_resources(struct device *dev) { uint32_t addr; dev->resources = 0; memset(&dev->resource, 0, sizeof(dev->resource)); pci_bridge_read_bases(dev); pci_read_bases(dev, 2); addr = pci_read_config32(dev, PCI_ROM_ADDRESS1); dev->rom_address = (addr == 0xffffffff)? 0 : addr; } static void pci_set_resource(struct device *dev, struct resource *resource) { unsigned long base, limit; unsigned char buf[10]; unsigned long align; /* Make certain the resource has actually been set */ if (!(resource->flags & IORESOURCE_SET)) { #if 1 printk_err("ERROR: %s %02x not allocated\n", dev_path(dev), resource->index); #endif return; } /* Only handle PCI memory and IO resources for now */ if (!(resource->flags & (IORESOURCE_MEM |IORESOURCE_IO))) return; if (resource->flags & IORESOURCE_MEM) { dev->command |= PCI_COMMAND_MEMORY; } if (resource->flags & IORESOURCE_IO) { dev->command |= PCI_COMMAND_IO; } if (resource->flags & IORESOURCE_PCI_BRIDGE) { dev->command |= PCI_COMMAND_MASTER; } /* Get the base address */ base = resource->base; /* Get the resource alignment */ align = 1UL << resource->align; /* Get the limit (rounded up) */ limit = base + ((resource->size + align - 1UL) & ~(align - 1UL)) -1UL; if (!(resource->flags & IORESOURCE_PCI_BRIDGE)) { /* * some chipsets allow us to set/clear the IO bit. * (e.g. VIA 82c686a.) So set it to be safe) */ limit = base + resource->size -1; if (resource->flags & IORESOURCE_IO) { base |= PCI_BASE_ADDRESS_SPACE_IO; } pci_write_config32(dev, resource->index, base & 0xffffffff); if (resource->flags & IORESOURCE_PCI64) { /* FIXME handle real 64bit base addresses */ pci_write_config32(dev, resource->index + 4, 0); } } else if (resource->index == PCI_IO_BASE) { /* set the IO ranges * WARNING: we don't really do 32-bit addressing for IO yet! */ compute_allocate_resource(&dev->link[0], resource, IORESOURCE_IO, IORESOURCE_IO); pci_write_config8(dev, PCI_IO_BASE, base >> 8); pci_write_config8(dev, PCI_IO_LIMIT, limit >> 8); pci_write_config16(dev, PCI_IO_BASE_UPPER16, 0); pci_write_config16(dev, PCI_IO_LIMIT_UPPER16, 0); } else if (resource->index == PCI_MEMORY_BASE) { /* set the memory range */ compute_allocate_resource(&dev->link[0], resource, IORESOURCE_MEM | IORESOURCE_PREFETCH, IORESOURCE_MEM); pci_write_config16(dev, PCI_MEMORY_BASE, base >> 16); pci_write_config16(dev, PCI_MEMORY_LIMIT, limit >> 16); } else if (resource->index == PCI_PREF_MEMORY_BASE) { /* set the prefetchable memory range * WARNING: we don't really do 64-bit addressing for prefetchable memory yet! */ compute_allocate_resource(&dev->link[0], resource, IORESOURCE_MEM | IORESOURCE_PREFETCH, IORESOURCE_MEM | IORESOURCE_PREFETCH); pci_write_config16(dev, PCI_PREF_MEMORY_BASE, base >> 16); pci_write_config16(dev, PCI_PREF_MEMORY_LIMIT, limit >> 16); pci_write_config32(dev, PCI_PREF_BASE_UPPER32, 0); pci_write_config32(dev, PCI_PREF_LIMIT_UPPER32, 0); } else { printk_err("ERROR: invalid resource->index %x\n", resource->index); } buf[0] = '\0'; if (resource->flags & IORESOURCE_PCI_BRIDGE) { sprintf(buf, "bus %d ", dev->link[0].secondary); } printk_debug( "%s %02x <- [0x%08lx - 0x%08lx] %s%s\n", dev_path(dev), resource->index, resource->base, limit, buf, (resource->flags & IORESOURCE_IO)? "io": (resource->flags & IORESOURCE_PREFETCH)? "prefmem": "mem"); return; } void pci_dev_set_resources(struct device *dev) { struct resource *resource, *last; unsigned link; uint8_t line; last = &dev->resource[dev->resources]; for(resource = &dev->resource[0]; resource < last; resource++) { pci_set_resource(dev, resource); } for(link = 0; link < dev->links; link++) { struct bus *bus; bus = &dev->link[link]; if (bus->children) { assign_resources(bus); } } /* set a default latency timer */ pci_write_config8(dev, PCI_LATENCY_TIMER, 0x40); /* set a default secondary latency timer */ if ((dev->hdr_type & 0x7f) == PCI_HEADER_TYPE_BRIDGE) { pci_write_config8(dev, PCI_SEC_LATENCY_TIMER, 0x40); } /* zero the irq settings */ line = pci_read_config8(dev, PCI_INTERRUPT_PIN); if (line) { pci_write_config8(dev, PCI_INTERRUPT_LINE, 0); } /* set the cache line size, so far 64 bytes is good for everyone */ pci_write_config8(dev, PCI_CACHE_LINE_SIZE, 64 >> 2); } void pci_dev_enable_resources(struct device *dev) { uint16_t command; command = pci_read_config16(dev, PCI_COMMAND); command |= dev->command; printk_debug("%s cmd <- %02x\n", dev_path(dev), command); pci_write_config16(dev, PCI_COMMAND, command); enable_childrens_resources(dev); } void pci_bus_enable_resources(struct device *dev) { uint16_t ctrl; ctrl = pci_read_config16(dev, PCI_BRIDGE_CONTROL); ctrl |= dev->link[0].bridge_ctrl; printk_debug("%s bridge ctrl <- %04x\n", dev_path(dev), ctrl); pci_write_config16(dev, PCI_BRIDGE_CONTROL, ctrl); pci_dev_enable_resources(dev); } struct device_operations default_pci_ops_dev = { .read_resources = pci_dev_read_resources, .set_resources = pci_dev_set_resources, .enable_resources = pci_dev_enable_resources, .init = 0, .scan_bus = 0, }; struct device_operations default_pci_ops_bus = { .read_resources = pci_bus_read_resources, .set_resources = pci_dev_set_resources, .enable_resources = pci_bus_enable_resources, .init = 0, .scan_bus = pci_scan_bridge, }; static void set_pci_ops(struct device *dev) { struct pci_driver *driver; if (dev->ops) { return; } /* Look through the list of setup drivers and find one for * this pci device */ for(driver = &pci_drivers[0]; driver != &epci_drivers[0]; driver++) { if ((driver->vendor == dev->vendor) && (driver->device == dev->device)) { dev->ops = driver->ops; #if 1 printk_debug("%s [%04x/%04x] %sops\n", dev_path(dev), driver->vendor, driver->device, (driver->ops->scan_bus?"bus ":"") ); #endif return; } } /* If I don't have a specific driver use the default operations */ switch(dev->hdr_type & 0x7f) { /* header type */ case PCI_HEADER_TYPE_NORMAL: /* standard header */ if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) goto bad; dev->ops = &default_pci_ops_dev; break; case PCI_HEADER_TYPE_BRIDGE: if ((dev->class >> 8) != PCI_CLASS_BRIDGE_PCI) goto bad; dev->ops = &default_pci_ops_bus; break; default: bad: printk_err("%s [%04x/%04x/%06x] has unknown header " "type %02x, ignoring.\n", dev_path(dev), dev->vendor, dev->device, dev->class >> 8, dev->hdr_type); } return; } /** * Given a bus and a devfn number, find the device structure * @param bus The bus structure * @param devfn a device/function number * @return pointer to the device structure */ static struct device *pci_scan_get_dev(struct device **list, unsigned int devfn) { struct device *dev = 0; for(; *list; list = &(*list)->sibling) { if ((*list)->path.u.pci.devfn == devfn) { /* Unlink from the list */ dev = *list; *list = (*list)->sibling; dev->sibling = 0; break; } } if (dev) { device_t child; /* Find the last child of our parent */ for(child = dev->bus->children; child && child->sibling; ) { child = child->sibling; } /* Place the device on the list of children of it's parent. */ if (child) { child->sibling = dev; } else { dev->bus->children = dev; } } return dev; } /** Scan the pci bus devices and bridges. * @param bus pointer to the bus structure * @param min_devfn minimum devfn to look at in the scan usually 0x00 * @param max_devfn maximum devfn to look at in the scan usually 0xff * @param max current bus number * @return The maximum bus number found, after scanning all subordinate busses */ unsigned int pci_scan_bus(struct bus *bus, unsigned min_devfn, unsigned max_devfn, unsigned int max) { unsigned int devfn; device_t dev; device_t old_devices; device_t child; printk_debug("PCI: pci_scan_bus for bus %d\n", bus->secondary); old_devices = bus->children; bus->children = 0; post_code(0x24); /* probe all devices on this bus with some optimization for non-existance and single funcion devices */ for (devfn = min_devfn; devfn <= max_devfn; devfn++) { uint32_t id, class; uint8_t hdr_type; /* First thing setup the device structure */ dev = pci_scan_get_dev(&old_devices, devfn); /* Detect if a device is present */ if (!dev) { struct device dummy; dummy.bus = bus; dummy.path.type = DEVICE_PATH_PCI; dummy.path.u.pci.devfn = devfn; id = pci_read_config32(&dummy, PCI_VENDOR_ID); /* some broken boards return 0 if a slot is empty: */ if ( (id == 0xffffffff) || (id == 0x00000000) || (id == 0x0000ffff) || (id == 0xffff0000)) { printk_spew("PCI: devfn 0x%x, bad id 0x%x\n", devfn, id); if (PCI_FUNC(devfn) == 0x00) { /* if this is a function 0 device and it is not present, skip to next device */ devfn += 0x07; } /* multi function device, skip to next function */ continue; } dev = alloc_dev(bus, &dummy.path); } else { /* Run the magic enable/disable sequence for the device */ if (dev->ops && dev->ops->enable) { dev->ops->enable(dev); } /* Now read the vendor and device id */ id = pci_read_config32(dev, PCI_VENDOR_ID); } /* Read the rest of the pci configuration information */ hdr_type = pci_read_config8(dev, PCI_HEADER_TYPE); class = pci_read_config32(dev, PCI_CLASS_REVISION); /* Store the interesting information in the device structure */ dev->vendor = id & 0xffff; dev->device = (id >> 16) & 0xffff; dev->hdr_type = hdr_type; /* class code, the upper 3 bytes of PCI_CLASS_REVISION */ dev->class = class >> 8; /* Look at the vendor and device id, or at least the * header type and class and figure out which set of configuration * methods to use. */ if (!dev->ops) { set_pci_ops(dev); /* Error if we don't have some pci operations for it */ if (!dev->ops) { printk_err("%s No device operations\n", dev_path(dev)); continue; } /* Now run the magic enable/disable sequence for the device */ if (dev->ops && dev->ops->enable) { dev->ops->enable(dev); } } printk_debug("%s [%04x/%04x] %s\n", dev_path(dev), dev->vendor, dev->device, dev->enable?"enabled": "disabled"); if (PCI_FUNC(devfn) == 0x00 && (hdr_type & 0x80) != 0x80) { /* if this is not a multi function device, don't waste time probe another function. Skip to next device. */ devfn += 0x07; } } post_code(0x25); for(child = bus->children; child; child = child->sibling) { if (!child->ops->scan_bus) { continue; } max = child->ops->scan_bus(child, max); } /* * We've scanned the bus and so we know all about what's on * the other side of any bridges that may be on this bus plus * any devices. * * Return how far we've got finding sub-buses. */ printk_debug("PCI: pci_scan_bus returning with max=%02x\n", max); post_code(0x55); return max; } /** Scan the bus, first for bridges and next for devices. * @param pci_bus pointer to the bus structure * @return The maximum bus number found, after scanning all subordinate busses */ unsigned int pci_scan_bridge(struct device *dev, unsigned int max) { struct bus *bus; uint32_t buses; uint16_t cr; bus = &dev->link[0]; dev->links = 1; /* Set up the primary, secondary and subordinate bus numbers. We have * no idea how many buses are behind this bridge yet, so we set the * subordinate bus number to 0xff for the moment */ bus->secondary = ++max; bus->subordinate = 0xff; /* Clear all status bits and turn off memory, I/O and master enables. */ cr = pci_read_config16(dev, PCI_COMMAND); pci_write_config16(dev, PCI_COMMAND, 0x0000); pci_write_config16(dev, PCI_STATUS, 0xffff); /* * Read the existing primary/secondary/subordinate bus * number configuration. */ buses = pci_read_config32(dev, PCI_PRIMARY_BUS); /* Configure the bus numbers for this bridge: the configuration * transactions will not be propagated by the bridge if it is not * correctly configured */ buses &= 0xff000000; buses |= (((unsigned int) (dev->bus->secondary) << 0) | ((unsigned int) (bus->secondary) << 8) | ((unsigned int) (bus->subordinate) << 16)); pci_write_config32(dev, PCI_PRIMARY_BUS, buses); /* Now we can scan all subordinate buses i.e. the bus hehind the bridge */ max = pci_scan_bus(bus, 0x00, 0xff, max); /* We know the number of buses behind this bridge. Set the subordinate * bus number to its real value */ bus->subordinate = max; buses = (buses & 0xff00ffff) | ((unsigned int) (bus->subordinate) << 16); pci_write_config32(dev, PCI_PRIMARY_BUS, buses); pci_write_config16(dev, PCI_COMMAND, cr); return max; }