pci_common.c

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/* $Id: pci_common.c,v 1.12 2000/05/01 06:32:49 davem Exp $
 * pci_common.c: PCI controller common support.
 *
 * Copyright (C) 1999 David S. Miller ([e-mail])
 */

#include <linux/string.h>
#include <linux/malloc.h>
#include <linux/init.h>

#include <asm/pbm.h>

/* Find the OBP PROM device tree node for a PCI device.
 * Return zero if not found.
 */
static int __init find_device_prom_node(struct pci_pbm_info *pbm,
					struct pci_dev *pdev,
					int bus_prom_node,
					struct linux_prom_pci_registers *pregs,
					int *nregs)
{
	int node;

	/*
	 * Return the PBM's PROM node in case we are it's PCI device,
	 * as the PBM's reg property is different to standard PCI reg
	 * properties. We would delete this device entry otherwise,
	 * which confuses XFree86's device probing...
	 */
	if ((pdev->bus->number == pbm->pci_bus->number) && (pdev->devfn == 0) &&
	    (pdev->vendor == PCI_VENDOR_ID_SUN) &&
	    (pdev->device == PCI_DEVICE_ID_SUN_PBM)) {
		*nregs = 0;
		return bus_prom_node;
	}

	node = prom_getchild(bus_prom_node);
	while (node != 0) {
		int err = prom_getproperty(node, "reg",
					   (char *)pregs,
					   sizeof(*pregs) * PROMREG_MAX);
		if (err == 0 || err == -1)
			goto do_next_sibling;
		if (((pregs[0].phys_hi >> 8) & 0xff) == pdev->devfn) {
			*nregs = err / sizeof(*pregs);
			return node;
		}

	do_next_sibling:
		node = prom_getsibling(node);
	}
	return 0;
}

/* Remove a PCI device from the device trees, then
 * free it up.  Note that this must run before
 * the device's resources are registered because we
 * do not handle unregistering them here.
 */
static void pci_device_delete(struct pci_dev *pdev)
{
	list_del(&pdev->global_list);
	list_del(&pdev->bus_list);

	/* Ok, all references are gone, free it up. */
	kfree(pdev);
}

/* Older versions of OBP on PCI systems encode 64-bit MEM
 * space assignments incorrectly, this fixes them up.
 */
static void __init fixup_obp_assignments(struct pcidev_cookie *pcp)
{
	int i;

	for (i = 0; i < pcp->num_prom_assignments; i++) {
		struct linux_prom_pci_registers *ap;
		int space;

		ap = &pcp->prom_assignments[i];
		space = ap->phys_hi >> 24;
		if ((space & 0x3) == 2 &&
		    (space & 0x4) != 0) {
			ap->phys_hi &= ~(0x7 << 24);
			ap->phys_hi |= 0x3 << 24;
		}
	}
}

/* Fill in the PCI device cookie sysdata for the given
 * PCI device.  This cookie is the means by which one
 * can get to OBP and PCI controller specific information
 * for a PCI device.
 */
static void __init pdev_cookie_fillin(struct pci_pbm_info *pbm,
				      struct pci_dev *pdev,
				      int bus_prom_node)
{
	struct linux_prom_pci_registers pregs[PROMREG_MAX];
	struct pcidev_cookie *pcp;
	int device_prom_node, nregs, err;

	device_prom_node = find_device_prom_node(pbm, pdev, bus_prom_node,
						 pregs, &nregs);
	if (device_prom_node == 0) {
		/* If it is not in the OBP device tree then
		 * there must be a damn good reason for it.
		 *
		 * So what we do is delete the device from the
		 * PCI device tree completely.  This scenerio
		 * is seen, for example, on CP1500 for the
		 * second EBUS/HappyMeal pair if the external
		 * connector for it is not present.
		 */
		pci_device_delete(pdev);
		return;
	}

	pcp = kmalloc(sizeof(*pcp), GFP_ATOMIC);
	if (pcp == NULL) {
		prom_printf("PCI_COOKIE: Fatal malloc error, aborting...\n");
		prom_halt();
	}
	pcp->pbm = pbm;
	pcp->prom_node = device_prom_node;
	memcpy(pcp->prom_regs, pregs, sizeof(pcp->prom_regs));
	pcp->num_prom_regs = nregs;
	err = prom_getproperty(device_prom_node, "name",
			       pcp->prom_name, sizeof(pcp->prom_name));
	if (err > 0)
		pcp->prom_name[err] = 0;
	else
		pcp->prom_name[0] = 0;
	if (strcmp(pcp->prom_name, "ebus") == 0) {
		struct linux_prom_ebus_ranges erng[PROM_PCIRNG_MAX];
		int iter;

		/* EBUS is special... */
		err = prom_getproperty(device_prom_node, "ranges",
				       (char *)&erng[0], sizeof(erng));
		if (err == 0 || err == -1) {
			prom_printf("EBUS: Fatal error, no range property\n");
			prom_halt();
		}
		err = (err / sizeof(erng[0]));
		for(iter = 0; iter < err; iter++) {
			struct linux_prom_ebus_ranges *ep = &erng[iter];
			struct linux_prom_pci_registers *ap;

			ap = &pcp->prom_assignments[iter];

			ap->phys_hi = ep->parent_phys_hi;
			ap->phys_mid = ep->parent_phys_mid;
			ap->phys_lo = ep->parent_phys_lo;
			ap->size_hi = 0;
			ap->size_lo = ep->size;
		}
		pcp->num_prom_assignments = err;
	} else {
		err = prom_getproperty(device_prom_node,
				       "assigned-addresses",
				       (char *)pcp->prom_assignments,
				       sizeof(pcp->prom_assignments));
		if (err == 0 || err == -1)
			pcp->num_prom_assignments = 0;
		else
			pcp->num_prom_assignments =
				(err / sizeof(pcp->prom_assignments[0]));
	}

	fixup_obp_assignments(pcp);

	pdev->sysdata = pcp;
}

void __init pci_fill_in_pbm_cookies(struct pci_bus *pbus,
				    struct pci_pbm_info *pbm,
				    int prom_node)
{
	struct list_head *walk = &pbus->devices;

	/* This loop is coded like this because the cookie
	 * fillin routine can delete devices from the tree.
	 */
	walk = walk->next;
	while (walk != &pbus->devices) {
		struct pci_dev *pdev = pci_dev_b(walk);
		struct list_head *walk_next = walk->next;

		pdev_cookie_fillin(pbm, pdev, prom_node);

		walk = walk_next;
	}

	walk = &pbus->children;
	walk = walk->next;
	while (walk != &pbus->children) {
		struct pci_bus *this_pbus = pci_bus_b(walk);
		struct pcidev_cookie *pcp = this_pbus->self->sysdata;
		struct list_head *walk_next = walk->next;

		pci_fill_in_pbm_cookies(this_pbus, pbm, pcp->prom_node);

		walk = walk_next;
	}
}

static void __init bad_assignment(struct linux_prom_pci_registers *ap,
				  struct resource *res,
				  int do_prom_halt)
{
	prom_printf("PCI: Bogus PROM assignment.\n");
	if (ap)
		prom_printf("PCI: phys[%08x:%08x:%08x] size[%08x:%08x]\n",
			    ap->phys_hi, ap->phys_mid, ap->phys_lo,
			    ap->size_hi, ap->size_lo);
	if (res)
		prom_printf("PCI: RES[%016lx-->%016lx:(%lx)]\n",
			    res->start, res->end, res->flags);
	prom_printf("Please email this information to [e-mail]\n");
	if (do_prom_halt)
		prom_halt();
}

static struct resource *
__init get_root_resource(struct linux_prom_pci_registers *ap,
			 struct pci_pbm_info *pbm)
{
	int space = (ap->phys_hi >> 24) & 3;

	switch (space) {
	case 0:
		/* Configuration space, silently ignore it. */
		return NULL;

	case 1:
		/* 16-bit IO space */
		return &pbm->io_space;

	case 2:
		/* 32-bit MEM space */
		return &pbm->mem_space;

	case 3:
		/* 64-bit MEM space, these are allocated out of
		 * the 32-bit mem_space range for the PBM, ie.
		 * we just zero out the upper 32-bits.
		 */
		return &pbm->mem_space;

	default:
		printk("PCI: What is resource space %x? "
		       "Tell [e-mail] about it!\n", space);
		return NULL;
	};
}

static struct resource *
__init get_device_resource(struct linux_prom_pci_registers *ap,
			   struct pci_dev *pdev)
{
	struct resource *res;
	int breg = (ap->phys_hi & 0xff);
	int space = (ap->phys_hi >> 24) & 3;

	switch (breg) {
	case  PCI_ROM_ADDRESS:
		/* It had better be MEM space. */
		if (space != 2)
			bad_assignment(ap, NULL, 0);

		res = &pdev->resource[PCI_ROM_RESOURCE];
		break;

	case PCI_BASE_ADDRESS_0:
	case PCI_BASE_ADDRESS_1:
	case PCI_BASE_ADDRESS_2:
	case PCI_BASE_ADDRESS_3:
	case PCI_BASE_ADDRESS_4:
	case PCI_BASE_ADDRESS_5:
		res = &pdev->resource[(breg - PCI_BASE_ADDRESS_0) / 4];
		break;

	default:
		bad_assignment(ap, NULL, 0);
		res = NULL;
		break;
	};

	return res;
}

static void __init pdev_record_assignments(struct pci_pbm_info *pbm,
					   struct pci_dev *pdev)
{
	struct pcidev_cookie *pcp = pdev->sysdata;
	int i;

	for (i = 0; i < pcp->num_prom_assignments; i++) {
		struct linux_prom_pci_registers *ap;
		struct resource *root, *res;

		/* The format of this property is specified in
		 * the PCI Bus Binding to IEEE1275-1994.
		 */
		ap = &pcp->prom_assignments[i];
		root = get_root_resource(ap, pbm);
		res = get_device_resource(ap, pdev);
		if (root == NULL || res == NULL)
			continue;

		/* Ok we know which resource this PROM assignment is
		 * for, sanity check it.
		 */
		if ((res->start & 0xffffffffUL) != ap->phys_lo)
			bad_assignment(ap, res, 1);

		/* If it is a 64-bit MEM space assignment, verify that
		 * the resource is too and that the upper 32-bits match.
		 */
		if (((ap->phys_hi >> 24) & 3) == 3) {
			if (((res->flags & IORESOURCE_MEM) == 0) ||
			    ((res->flags & PCI_BASE_ADDRESS_MEM_TYPE_MASK)
			     != PCI_BASE_ADDRESS_MEM_TYPE_64))
				bad_assignment(ap, res, 1);
			if ((res->start >> 32) != ap->phys_mid)
				bad_assignment(ap, res, 1);

			/* PBM cannot generate cpu initiated PIOs
			 * to the full 64-bit space.  Therefore the
			 * upper 32-bits better be zero.  If it is
			 * not, just skip it and we will assign it
			 * properly ourselves.
			 */
			if ((res->start >> 32) != 0UL) {
				printk(KERN_ERR "PCI: OBP assigns out of range MEM address "
				       "%016lx for region %ld on device %s\n",
				       res->start, (res - &pdev->resource[0]), pdev->name);
				continue;
			}
		}

		/* Adjust the resource into the physical address space
		 * of this PBM.
		 */
		pbm->parent->resource_adjust(pdev, res, root);

		if (request_resource(root, res) < 0) {
			/* OK, there is some conflict.  But this is fine
			 * since we'll reassign it in the fixup pass.
			 * Nevertheless notify the user that OBP made
			 * an error.
			 */
			printk(KERN_ERR "PCI: Address space collision on region %ld "
			       "of device %s\n",
			       (res - &pdev->resource[0]), pdev->name);
		}
	}
}

void __init pci_record_assignments(struct pci_pbm_info *pbm,
				   struct pci_bus *pbus)
{
	struct list_head *walk = &pbus->devices;

	for (walk = walk->next; walk != &pbus->devices; walk = walk->next)
		pdev_record_assignments(pbm, pci_dev_b(walk));

	walk = &pbus->children;
	for (walk = walk->next; walk != &pbus->children; walk = walk->next)
		pci_record_assignments(pbm, pci_bus_b(walk));
}

static void __init pdev_assign_unassigned(struct pci_pbm_info *pbm,
					  struct pci_dev *pdev)
{
	u32 reg;
	u16 cmd;
	int i, io_seen, mem_seen;

	io_seen = mem_seen = 0;
	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
		struct resource *root, *res;
		unsigned long size, min, max, align;

		res = &pdev->resource[i];

		if (res->flags & IORESOURCE_IO)
			io_seen++;
		else if (res->flags & IORESOURCE_MEM)
			mem_seen++;

		/* If it is already assigned or the resource does
		 * not exist, there is nothing to do.
		 */
		if (res->parent != NULL || res->flags == 0UL)
			continue;

		/* Determine the root we allocate from. */
		if (res->flags & IORESOURCE_IO) {
			root = &pbm->io_space;
			min = root->start + 0x400UL;
			max = root->end;
		} else {
			root = &pbm->mem_space;
			min = root->start;
			max = min + 0x80000000UL;
		}

		size = res->end - res->start;
		align = size + 1;
		if (allocate_resource(root, res, size + 1, min, max, align, NULL, NULL) < 0) {
			/* uh oh */
			prom_printf("PCI: Failed to allocate resource %d for %s\n",
				    i, pdev->name);
			prom_halt();
		}

		/* Update PCI config space. */
		pbm->parent->base_address_update(pdev, i);
	}

	/* Special case, disable the ROM.  Several devices
	 * act funny (ie. do not respond to memory space writes)
	 * when it is left enabled.  A good example are Qlogic,ISP
	 * adapters.
	 */
	pci_read_config_dword(pdev, PCI_ROM_ADDRESS, &reg);
	reg &= ~PCI_ROM_ADDRESS_ENABLE;
	pci_write_config_dword(pdev, PCI_ROM_ADDRESS, reg);

	/* If we saw I/O or MEM resources, enable appropriate
	 * bits in PCI command register.
	 */
	if (io_seen || mem_seen) {
		pci_read_config_word(pdev, PCI_COMMAND, &cmd);
		if (io_seen)