linux/drivers/pci/setup-res.c
Ralf Baechle fb0f2b40fa PCI legacy resource fix
Since commit 368c73d4f6 the kernel will try
to update the non-writeable BAR registers 0..3 of PIIX4 IDE adapters if
pci_assign_unassigned_resources() is used to do full resource assignment of
the bus.  This fails because in the PIIX4 these BAR registers have
implicitly assumed values and read back as zero; it used to work because
the kernel used to just write zero to that register the read back value did
match what was written.

The fix is a new resource flag IORESOURCE_PCI_FIXED used to mark a resource
as non-movable.  This will also be useful to keep other import system
resources from being moved around - for example system consoles on PCI
busses.

[akpm@osdl.org: cleanup]
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20 10:54:43 -08:00

266 lines
6.8 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;
/*
* Ignore non-moveable resources. This might be legacy resources for
* which no functional BAR register exists or another important
* system resource we should better not move around in system address
* space.
*/
if (res->flags & IORESOURCE_PCI_FIXED)
return;
pcibios_resource_to_bus(dev, &region, res);
pr_debug(" got res [%llx:%llx] bus [%lx:%lx] flags %lx for "
"BAR %d of %s\n", (unsigned long long)res->start,
(unsigned long long)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 [%llx:%llx]\n",
root ? "Address space collision on" :
"No parent found for",
resource, dtype, pci_name(dev),
(unsigned long long)res->start,
(unsigned long long)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;
resource_size_t 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:%llx@%llx for %s\n",
res->flags & IORESOURCE_IO ? "I/O" : "mem",
resno, (unsigned long long)size,
(unsigned long long)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;
resource_size_t r_align;
r = &dev->resource[i];
if (r->flags & IORESOURCE_PCI_FIXED)
continue;
r_align = r->end - r->start;
if (!(r->flags) || r->parent)
continue;
if (!r_align) {
printk(KERN_WARNING "PCI: Ignore bogus resource %d "
"[%llx:%llx] of %s\n",
i, (unsigned long long)r->start,
(unsigned long long)r->end, pci_name(dev));
continue;
}
r_align = (i < PCI_BRIDGE_RESOURCES) ? r_align + 1 : r->start;
for (list = head; ; list = list->next) {
resource_size_t 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;
}
}
}
}