linux/drivers/pci/setup-res.c
Kumar Gala 75acfecaa0 [PATCH] PCI: Add pci_assign_resource_fixed -- allow fixed address assignments
PCI: Add pci_assign_resource_fixed -- allow fixed address assignments

On some embedded systems the PCI address for hotplug devices are not only
known a priori but are required to be at a given PCI address for other
master in the system to be able to access.

An example of such a system would be an FPGA which is setup from user space
after the system has booted.  The FPGA may be access by DSPs in the system
and those DSPs expect the FPGA at a fixed PCI address.

Added pci_assign_resource_fixed() as a way to allow assignment of the PCI
devices's BARs at fixed PCI addresses.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-21 11:59:59 -07:00

246 lines
6.3 KiB
C

/*
* drivers/pci/setup-res.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.
*/
/* fixed for multiple pci buses, 1999 Andrea Arcangeli <andrea@suse.de> */
/*
* Nov 2000, Ivan Kokshaysky <ink@jurassic.park.msu.ru>
* Resource sorting
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/cache.h>
#include <linux/slab.h>
#include "pci.h"
void
pci_update_resource(struct pci_dev *dev, struct resource *res, int resno)
{
struct pci_bus_region region;
u32 new, check, mask;
int reg;
/* Ignore resources for unimplemented BARs and unused resource slots
for 64 bit BARs. */
if (!res->flags)
return;
pcibios_resource_to_bus(dev, &region, res);
pr_debug(" got res [%lx:%lx] bus [%lx:%lx] flags %lx for "
"BAR %d of %s\n", res->start, res->end,
region.start, region.end, res->flags, resno, pci_name(dev));
new = region.start | (res->flags & PCI_REGION_FLAG_MASK);
if (res->flags & IORESOURCE_IO)
mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
else
mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
if (resno < 6) {
reg = PCI_BASE_ADDRESS_0 + 4 * resno;
} else if (resno == PCI_ROM_RESOURCE) {
if (!(res->flags & IORESOURCE_ROM_ENABLE))
return;
new |= PCI_ROM_ADDRESS_ENABLE;
reg = dev->rom_base_reg;
} else {
/* Hmm, non-standard resource. */
return; /* kill uninitialised var warning */
}
pci_write_config_dword(dev, reg, new);
pci_read_config_dword(dev, reg, &check);
if ((new ^ check) & mask) {
printk(KERN_ERR "PCI: Error while updating region "
"%s/%d (%08x != %08x)\n", pci_name(dev), resno,
new, check);
}
if ((new & (PCI_BASE_ADDRESS_SPACE|PCI_BASE_ADDRESS_MEM_TYPE_MASK)) ==
(PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_64)) {
new = region.start >> 16 >> 16;
pci_write_config_dword(dev, reg + 4, new);
pci_read_config_dword(dev, reg + 4, &check);
if (check != new) {
printk(KERN_ERR "PCI: Error updating region "
"%s/%d (high %08x != %08x)\n",
pci_name(dev), resno, new, check);
}
}
res->flags &= ~IORESOURCE_UNSET;
pr_debug("PCI: moved device %s resource %d (%lx) to %x\n",
pci_name(dev), resno, res->flags,
new & ~PCI_REGION_FLAG_MASK);
}
int __devinit
pci_claim_resource(struct pci_dev *dev, int resource)
{
struct resource *res = &dev->resource[resource];
struct resource *root = NULL;
char *dtype = resource < PCI_BRIDGE_RESOURCES ? "device" : "bridge";
int err;
root = pcibios_select_root(dev, res);
err = -EINVAL;
if (root != NULL)
err = insert_resource(root, res);
if (err) {
printk(KERN_ERR "PCI: %s region %d of %s %s [%lx:%lx]\n",
root ? "Address space collision on" :
"No parent found for",
resource, dtype, pci_name(dev), res->start, res->end);
}
return err;
}
EXPORT_SYMBOL_GPL(pci_claim_resource);
int pci_assign_resource(struct pci_dev *dev, int resno)
{
struct pci_bus *bus = dev->bus;
struct resource *res = dev->resource + resno;
unsigned long size, min, align;
int ret;
size = res->end - res->start + 1;
min = (res->flags & IORESOURCE_IO) ? PCIBIOS_MIN_IO : PCIBIOS_MIN_MEM;
/* The bridge resources are special, as their
size != alignment. Sizing routines return
required alignment in the "start" field. */
align = (resno < PCI_BRIDGE_RESOURCES) ? size : res->start;
/* First, try exact prefetching match.. */
ret = pci_bus_alloc_resource(bus, res, size, align, min,
IORESOURCE_PREFETCH,
pcibios_align_resource, dev);
if (ret < 0 && (res->flags & IORESOURCE_PREFETCH)) {
/*
* That failed.
*
* But a prefetching area can handle a non-prefetching
* window (it will just not perform as well).
*/
ret = pci_bus_alloc_resource(bus, res, size, align, min, 0,
pcibios_align_resource, dev);
}
if (ret) {
printk(KERN_ERR "PCI: Failed to allocate %s resource #%d:%lx@%lx for %s\n",
res->flags & IORESOURCE_IO ? "I/O" : "mem",
resno, size, res->start, pci_name(dev));
} else if (resno < PCI_BRIDGE_RESOURCES) {
pci_update_resource(dev, res, resno);
}
return ret;
}
#ifdef CONFIG_EMBEDDED
int pci_assign_resource_fixed(struct pci_dev *dev, int resno)
{
struct pci_bus *bus = dev->bus;
struct resource *res = dev->resource + resno;
unsigned int type_mask;
int i, ret = -EBUSY;
type_mask = IORESOURCE_IO | IORESOURCE_MEM | IORESOURCE_PREFETCH;
for (i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
struct resource *r = bus->resource[i];
if (!r)
continue;
/* type_mask must match */
if ((res->flags ^ r->flags) & type_mask)
continue;
ret = request_resource(r, res);
if (ret == 0)
break;
}
if (ret) {
printk(KERN_ERR "PCI: Failed to allocate %s resource "
"#%d:%llx@%llx for %s\n",
res->flags & IORESOURCE_IO ? "I/O" : "mem",
resno, (unsigned long long)(res->end - res->start + 1),
(unsigned long long)res->start, pci_name(dev));
} else if (resno < PCI_BRIDGE_RESOURCES) {
pci_update_resource(dev, res, resno);
}
return ret;
}
EXPORT_SYMBOL_GPL(pci_assign_resource_fixed);
#endif
/* Sort resources by alignment */
void __devinit
pdev_sort_resources(struct pci_dev *dev, struct resource_list *head)
{
int i;
for (i = 0; i < PCI_NUM_RESOURCES; i++) {
struct resource *r;
struct resource_list *list, *tmp;
unsigned long r_align;
r = &dev->resource[i];
r_align = r->end - r->start;
if (!(r->flags) || r->parent)
continue;
if (!r_align) {
printk(KERN_WARNING "PCI: Ignore bogus resource %d "
"[%lx:%lx] of %s\n",
i, r->start, r->end, pci_name(dev));
continue;
}
r_align = (i < PCI_BRIDGE_RESOURCES) ? r_align + 1 : r->start;
for (list = head; ; list = list->next) {
unsigned long align = 0;
struct resource_list *ln = list->next;
int idx;
if (ln) {
idx = ln->res - &ln->dev->resource[0];
align = (idx < PCI_BRIDGE_RESOURCES) ?
ln->res->end - ln->res->start + 1 :
ln->res->start;
}
if (r_align > align) {
tmp = kmalloc(sizeof(*tmp), GFP_KERNEL);
if (!tmp)
panic("pdev_sort_resources(): "
"kmalloc() failed!\n");
tmp->next = ln;
tmp->res = r;
tmp->dev = dev;
list->next = tmp;
break;
}
}
}
}