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| author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 | 
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 | 
| commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
| tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/pci/setup-bus.c | |
| download | olio-linux-3.10-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz olio-linux-3.10-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip  | |
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/pci/setup-bus.c')
| -rw-r--r-- | drivers/pci/setup-bus.c | 552 | 
1 files changed, 552 insertions, 0 deletions
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c new file mode 100644 index 00000000000..1ba84be0b4c --- /dev/null +++ b/drivers/pci/setup-bus.c @@ -0,0 +1,552 @@ +/* + *	drivers/pci/setup-bus.c + * + * Extruded from code written by + *      Dave Rusling (david.rusling@reo.mts.dec.com) + *      David Mosberger (davidm@cs.arizona.edu) + *	David Miller (davem@redhat.com) + * + * Support routines for initializing a PCI subsystem. + */ + +/* + * Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru> + *	     PCI-PCI bridges cleanup, sorted resource allocation. + * Feb 2002, Ivan Kokshaysky <ink@jurassic.park.msu.ru> + *	     Converted to allocation in 3 passes, which gives + *	     tighter packing. Prefetchable range support. + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/errno.h> +#include <linux/ioport.h> +#include <linux/cache.h> +#include <linux/slab.h> + + +#define DEBUG_CONFIG 1 +#if DEBUG_CONFIG +#define DBG(x...)     printk(x) +#else +#define DBG(x...) +#endif + +#define ROUND_UP(x, a)		(((x) + (a) - 1) & ~((a) - 1)) + +/* + * FIXME: IO should be max 256 bytes.  However, since we may + * have a P2P bridge below a cardbus bridge, we need 4K. + */ +#define CARDBUS_IO_SIZE		(4096) +#define CARDBUS_MEM_SIZE	(32*1024*1024) + +static void __devinit +pbus_assign_resources_sorted(struct pci_bus *bus) +{ +	struct pci_dev *dev; +	struct resource *res; +	struct resource_list head, *list, *tmp; +	int idx; + +	bus->bridge_ctl &= ~PCI_BRIDGE_CTL_VGA; + +	head.next = NULL; +	list_for_each_entry(dev, &bus->devices, bus_list) { +		u16 class = dev->class >> 8; + +		/* Don't touch classless devices and host bridges.  */ +		if (class == PCI_CLASS_NOT_DEFINED || +		    class == PCI_CLASS_BRIDGE_HOST) +			continue; + +		if (class == PCI_CLASS_DISPLAY_VGA || +		    class == PCI_CLASS_NOT_DEFINED_VGA) +			bus->bridge_ctl |= PCI_BRIDGE_CTL_VGA; + +		pdev_sort_resources(dev, &head); +	} + +	for (list = head.next; list;) { +		res = list->res; +		idx = res - &list->dev->resource[0]; +		pci_assign_resource(list->dev, idx); +		tmp = list; +		list = list->next; +		kfree(tmp); +	} +} + +static void __devinit +pci_setup_cardbus(struct pci_bus *bus) +{ +	struct pci_dev *bridge = bus->self; +	struct pci_bus_region region; + +	printk("PCI: Bus %d, cardbus bridge: %s\n", +		bus->number, pci_name(bridge)); + +	pcibios_resource_to_bus(bridge, ®ion, bus->resource[0]); +	if (bus->resource[0]->flags & IORESOURCE_IO) { +		/* +		 * The IO resource is allocated a range twice as large as it +		 * would normally need.  This allows us to set both IO regs. +		 */ +		printk("  IO window: %08lx-%08lx\n", +			region.start, region.end); +		pci_write_config_dword(bridge, PCI_CB_IO_BASE_0, +					region.start); +		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_0, +					region.end); +	} + +	pcibios_resource_to_bus(bridge, ®ion, bus->resource[1]); +	if (bus->resource[1]->flags & IORESOURCE_IO) { +		printk("  IO window: %08lx-%08lx\n", +			region.start, region.end); +		pci_write_config_dword(bridge, PCI_CB_IO_BASE_1, +					region.start); +		pci_write_config_dword(bridge, PCI_CB_IO_LIMIT_1, +					region.end); +	} + +	pcibios_resource_to_bus(bridge, ®ion, bus->resource[2]); +	if (bus->resource[2]->flags & IORESOURCE_MEM) { +		printk("  PREFETCH window: %08lx-%08lx\n", +			region.start, region.end); +		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_0, +					region.start); +		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_0, +					region.end); +	} + +	pcibios_resource_to_bus(bridge, ®ion, bus->resource[3]); +	if (bus->resource[3]->flags & IORESOURCE_MEM) { +		printk("  MEM window: %08lx-%08lx\n", +			region.start, region.end); +		pci_write_config_dword(bridge, PCI_CB_MEMORY_BASE_1, +					region.start); +		pci_write_config_dword(bridge, PCI_CB_MEMORY_LIMIT_1, +					region.end); +	} +} + +/* Initialize bridges with base/limit values we have collected. +   PCI-to-PCI Bridge Architecture Specification rev. 1.1 (1998) +   requires that if there is no I/O ports or memory behind the +   bridge, corresponding range must be turned off by writing base +   value greater than limit to the bridge's base/limit registers. + +   Note: care must be taken when updating I/O base/limit registers +   of bridges which support 32-bit I/O. This update requires two +   config space writes, so it's quite possible that an I/O window of +   the bridge will have some undesirable address (e.g. 0) after the +   first write. Ditto 64-bit prefetchable MMIO.  */ +static void __devinit +pci_setup_bridge(struct pci_bus *bus) +{ +	struct pci_dev *bridge = bus->self; +	struct pci_bus_region region; +	u32 l, io_upper16; + +	DBG(KERN_INFO "PCI: Bridge: %s\n", pci_name(bridge)); + +	/* Set up the top and bottom of the PCI I/O segment for this bus. */ +	pcibios_resource_to_bus(bridge, ®ion, bus->resource[0]); +	if (bus->resource[0]->flags & IORESOURCE_IO) { +		pci_read_config_dword(bridge, PCI_IO_BASE, &l); +		l &= 0xffff0000; +		l |= (region.start >> 8) & 0x00f0; +		l |= region.end & 0xf000; +		/* Set up upper 16 bits of I/O base/limit. */ +		io_upper16 = (region.end & 0xffff0000) | (region.start >> 16); +		DBG(KERN_INFO "  IO window: %04lx-%04lx\n", +				region.start, region.end); +	} +	else { +		/* Clear upper 16 bits of I/O base/limit. */ +		io_upper16 = 0; +		l = 0x00f0; +		DBG(KERN_INFO "  IO window: disabled.\n"); +	} +	/* Temporarily disable the I/O range before updating PCI_IO_BASE. */ +	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, 0x0000ffff); +	/* Update lower 16 bits of I/O base/limit. */ +	pci_write_config_dword(bridge, PCI_IO_BASE, l); +	/* Update upper 16 bits of I/O base/limit. */ +	pci_write_config_dword(bridge, PCI_IO_BASE_UPPER16, io_upper16); + +	/* Set up the top and bottom of the PCI Memory segment +	   for this bus. */ +	pcibios_resource_to_bus(bridge, ®ion, bus->resource[1]); +	if (bus->resource[1]->flags & IORESOURCE_MEM) { +		l = (region.start >> 16) & 0xfff0; +		l |= region.end & 0xfff00000; +		DBG(KERN_INFO "  MEM window: %08lx-%08lx\n", +				region.start, region.end); +	} +	else { +		l = 0x0000fff0; +		DBG(KERN_INFO "  MEM window: disabled.\n"); +	} +	pci_write_config_dword(bridge, PCI_MEMORY_BASE, l); + +	/* Clear out the upper 32 bits of PREF limit. +	   If PCI_PREF_BASE_UPPER32 was non-zero, this temporarily +	   disables PREF range, which is ok. */ +	pci_write_config_dword(bridge, PCI_PREF_LIMIT_UPPER32, 0); + +	/* Set up PREF base/limit. */ +	pcibios_resource_to_bus(bridge, ®ion, bus->resource[2]); +	if (bus->resource[2]->flags & IORESOURCE_PREFETCH) { +		l = (region.start >> 16) & 0xfff0; +		l |= region.end & 0xfff00000; +		DBG(KERN_INFO "  PREFETCH window: %08lx-%08lx\n", +				region.start, region.end); +	} +	else { +		l = 0x0000fff0; +		DBG(KERN_INFO "  PREFETCH window: disabled.\n"); +	} +	pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, l); + +	/* Clear out the upper 32 bits of PREF base. */ +	pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, 0); + +	pci_write_config_word(bridge, PCI_BRIDGE_CONTROL, bus->bridge_ctl); +} + +/* Check whether the bridge supports optional I/O and +   prefetchable memory ranges. If not, the respective +   base/limit registers must be read-only and read as 0. */ +static void __devinit +pci_bridge_check_ranges(struct pci_bus *bus) +{ +	u16 io; +	u32 pmem; +	struct pci_dev *bridge = bus->self; +	struct resource *b_res; + +	b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; +	b_res[1].flags |= IORESOURCE_MEM; + +	pci_read_config_word(bridge, PCI_IO_BASE, &io); +	if (!io) { +		pci_write_config_word(bridge, PCI_IO_BASE, 0xf0f0); +		pci_read_config_word(bridge, PCI_IO_BASE, &io); + 		pci_write_config_word(bridge, PCI_IO_BASE, 0x0); + 	} + 	if (io) +		b_res[0].flags |= IORESOURCE_IO; +	/*  DECchip 21050 pass 2 errata: the bridge may miss an address +	    disconnect boundary by one PCI data phase. +	    Workaround: do not use prefetching on this device. */ +	if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001) +		return; +	pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem); +	if (!pmem) { +		pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, +					       0xfff0fff0); +		pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem); +		pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0); +	} +	if (pmem) +		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH; +} + +/* Helper function for sizing routines: find first available +   bus resource of a given type. Note: we intentionally skip +   the bus resources which have already been assigned (that is, +   have non-NULL parent resource). */ +static struct resource * __devinit +find_free_bus_resource(struct pci_bus *bus, unsigned long type) +{ +	int i; +	struct resource *r; +	unsigned long type_mask = IORESOURCE_IO | IORESOURCE_MEM | +				  IORESOURCE_PREFETCH; + +	for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) { +		r = bus->resource[i]; +		if (r && (r->flags & type_mask) == type && !r->parent) +			return r; +	} +	return NULL; +} + +/* Sizing the IO windows of the PCI-PCI bridge is trivial, +   since these windows have 4K granularity and the IO ranges +   of non-bridge PCI devices are limited to 256 bytes. +   We must be careful with the ISA aliasing though. */ +static void __devinit +pbus_size_io(struct pci_bus *bus) +{ +	struct pci_dev *dev; +	struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO); +	unsigned long size = 0, size1 = 0; + +	if (!b_res) + 		return; + +	list_for_each_entry(dev, &bus->devices, bus_list) { +		int i; + +		for (i = 0; i < PCI_NUM_RESOURCES; i++) { +			struct resource *r = &dev->resource[i]; +			unsigned long r_size; + +			if (r->parent || !(r->flags & IORESOURCE_IO)) +				continue; +			r_size = r->end - r->start + 1; + +			if (r_size < 0x400) +				/* Might be re-aligned for ISA */ +				size += r_size; +			else +				size1 += r_size; +		} +	} +/* To be fixed in 2.5: we should have sort of HAVE_ISA +   flag in the struct pci_bus. */ +#if defined(CONFIG_ISA) || defined(CONFIG_EISA) +	size = (size & 0xff) + ((size & ~0xffUL) << 2); +#endif +	size = ROUND_UP(size + size1, 4096); +	if (!size) { +		b_res->flags = 0; +		return; +	} +	/* Alignment of the IO window is always 4K */ +	b_res->start = 4096; +	b_res->end = b_res->start + size - 1; +} + +/* Calculate the size of the bus and minimal alignment which +   guarantees that all child resources fit in this size. */ +static int __devinit +pbus_size_mem(struct pci_bus *bus, unsigned long mask, unsigned long type) +{ +	struct pci_dev *dev; +	unsigned long min_align, align, size; +	unsigned long aligns[12];	/* Alignments from 1Mb to 2Gb */ +	int order, max_order; +	struct resource *b_res = find_free_bus_resource(bus, type); + +	if (!b_res) +		return 0; + +	memset(aligns, 0, sizeof(aligns)); +	max_order = 0; +	size = 0; + +	list_for_each_entry(dev, &bus->devices, bus_list) { +		int i; +		 +		for (i = 0; i < PCI_NUM_RESOURCES; i++) { +			struct resource *r = &dev->resource[i]; +			unsigned long r_size; + +			if (r->parent || (r->flags & mask) != type) +				continue; +			r_size = r->end - r->start + 1; +			/* For bridges size != alignment */ +			align = (i < PCI_BRIDGE_RESOURCES) ? r_size : r->start; +			order = __ffs(align) - 20; +			if (order > 11) { +				printk(KERN_WARNING "PCI: region %s/%d " +				       "too large: %lx-%lx\n", +				       pci_name(dev), i, r->start, r->end); +				r->flags = 0; +				continue; +			} +			size += r_size; +			if (order < 0) +				order = 0; +			/* Exclude ranges with size > align from +			   calculation of the alignment. */ +			if (r_size == align) +				aligns[order] += align; +			if (order > max_order) +				max_order = order; +		} +	} + +	align = 0; +	min_align = 0; +	for (order = 0; order <= max_order; order++) { +		unsigned long align1 = 1UL << (order + 20); + +		if (!align) +			min_align = align1; +		else if (ROUND_UP(align + min_align, min_align) < align1) +			min_align = align1 >> 1; +		align += aligns[order]; +	} +	size = ROUND_UP(size, min_align); +	if (!size) { +		b_res->flags = 0; +		return 1; +	} +	b_res->start = min_align; +	b_res->end = size + min_align - 1; +	return 1; +} + +static void __devinit +pci_bus_size_cardbus(struct pci_bus *bus) +{ +	struct pci_dev *bridge = bus->self; +	struct resource *b_res = &bridge->resource[PCI_BRIDGE_RESOURCES]; +	u16 ctrl; + +	/* +	 * Reserve some resources for CardBus.  We reserve +	 * a fixed amount of bus space for CardBus bridges. +	 */ +	b_res[0].start = CARDBUS_IO_SIZE; +	b_res[0].end = b_res[0].start + CARDBUS_IO_SIZE - 1; +	b_res[0].flags |= IORESOURCE_IO; + +	b_res[1].start = CARDBUS_IO_SIZE; +	b_res[1].end = b_res[1].start + CARDBUS_IO_SIZE - 1; +	b_res[1].flags |= IORESOURCE_IO; + +	/* +	 * Check whether prefetchable memory is supported +	 * by this bridge. +	 */ +	pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); +	if (!(ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0)) { +		ctrl |= PCI_CB_BRIDGE_CTL_PREFETCH_MEM0; +		pci_write_config_word(bridge, PCI_CB_BRIDGE_CONTROL, ctrl); +		pci_read_config_word(bridge, PCI_CB_BRIDGE_CONTROL, &ctrl); +	} + +	/* +	 * If we have prefetchable memory support, allocate +	 * two regions.  Otherwise, allocate one region of +	 * twice the size. +	 */ +	if (ctrl & PCI_CB_BRIDGE_CTL_PREFETCH_MEM0) { +		b_res[2].start = CARDBUS_MEM_SIZE; +		b_res[2].end = b_res[2].start + CARDBUS_MEM_SIZE - 1; +		b_res[2].flags |= IORESOURCE_MEM | IORESOURCE_PREFETCH; + +		b_res[3].start = CARDBUS_MEM_SIZE; +		b_res[3].end = b_res[3].start + CARDBUS_MEM_SIZE - 1; +		b_res[3].flags |= IORESOURCE_MEM; +	} else { +		b_res[3].start = CARDBUS_MEM_SIZE * 2; +		b_res[3].end = b_res[3].start + CARDBUS_MEM_SIZE * 2 - 1; +		b_res[3].flags |= IORESOURCE_MEM; +	} +} + +void __devinit +pci_bus_size_bridges(struct pci_bus *bus) +{ +	struct pci_dev *dev; +	unsigned long mask, prefmask; + +	list_for_each_entry(dev, &bus->devices, bus_list) { +		struct pci_bus *b = dev->subordinate; +		if (!b) +			continue; + +		switch (dev->class >> 8) { +		case PCI_CLASS_BRIDGE_CARDBUS: +			pci_bus_size_cardbus(b); +			break; + +		case PCI_CLASS_BRIDGE_PCI: +		default: +			pci_bus_size_bridges(b); +			break; +		} +	} + +	/* The root bus? */ +	if (!bus->self) +		return; + +	switch (bus->self->class >> 8) { +	case PCI_CLASS_BRIDGE_CARDBUS: +		/* don't size cardbuses yet. */ +		break; + +	case PCI_CLASS_BRIDGE_PCI: +		pci_bridge_check_ranges(bus); +	default: +		pbus_size_io(bus); +		/* If the bridge supports prefetchable range, size it +		   separately. If it doesn't, or its prefetchable window +		   has already been allocated by arch code, try +		   non-prefetchable range for both types of PCI memory +		   resources. */ +		mask = IORESOURCE_MEM; +		prefmask = IORESOURCE_MEM | IORESOURCE_PREFETCH; +		if (pbus_size_mem(bus, prefmask, prefmask)) +			mask = prefmask; /* Success, size non-prefetch only. */ +		pbus_size_mem(bus, mask, IORESOURCE_MEM); +		break; +	} +} +EXPORT_SYMBOL(pci_bus_size_bridges); + +void __devinit +pci_bus_assign_resources(struct pci_bus *bus) +{ +	struct pci_bus *b; +	struct pci_dev *dev; + +	pbus_assign_resources_sorted(bus); + +	if (bus->bridge_ctl & PCI_BRIDGE_CTL_VGA) { +		/* Propagate presence of the VGA to upstream bridges */ +		for (b = bus; b->parent; b = b->parent) { +			b->bridge_ctl |= PCI_BRIDGE_CTL_VGA; +		} +	} +	list_for_each_entry(dev, &bus->devices, bus_list) { +		b = dev->subordinate; +		if (!b) +			continue; + +		pci_bus_assign_resources(b); + +		switch (dev->class >> 8) { +		case PCI_CLASS_BRIDGE_PCI: +			pci_setup_bridge(b); +			break; + +		case PCI_CLASS_BRIDGE_CARDBUS: +			pci_setup_cardbus(b); +			break; + +		default: +			printk(KERN_INFO "PCI: not setting up bridge %s " +			       "for bus %d\n", pci_name(dev), b->number); +			break; +		} +	} +} +EXPORT_SYMBOL(pci_bus_assign_resources); + +void __init +pci_assign_unassigned_resources(void) +{ +	struct pci_bus *bus; + +	/* Depth first, calculate sizes and alignments of all +	   subordinate buses. */ +	list_for_each_entry(bus, &pci_root_buses, node) { +		pci_bus_size_bridges(bus); +	} +	/* Depth last, allocate resources and update the hardware. */ +	list_for_each_entry(bus, &pci_root_buses, node) { +		pci_bus_assign_resources(bus); +		pci_enable_bridges(bus); +	} +}  |