android_kernel_google_msm/drivers/eisa/pci_eisa.c
Yinghai Lu 91777f102b EISA/PCI: Fix bus res reference
commit 2cfda637e2 upstream.

Matthew found that 3.8.3 is having problems with an old (ancient)
PCI-to-EISA bridge, the Intel 82375. It worked with the 3.2 kernel.
He identified the 82375, but doesn't assign the struct resource *res
pointer inside the struct eisa_root_device, and panics.

pci_eisa_init() was using bus->resource[] directly instead of
pci_bus_resource_n().  The bus->resource[] array is a PCI-internal
implementation detail, and after commit 45ca9e97 (PCI: add helpers for
building PCI bus resource lists) and commit 0efd5aab (PCI: add struct
pci_host_bridge_window with CPU/bus address offset), bus->resource[] is not
used for PCI root buses any more.

The 82375 is a subtractive-decode PCI device, so handle it the same
way we handle PCI-PCI bridges in subtractive-decode mode in
pci_read_bridge_bases().

[bhelgaas: changelog]
Reported-by: Matthew Whitehead <mwhitehe@redhat.com>
Tested-by: Matthew Whitehead <mwhitehe@redhat.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-12 09:38:44 -07:00

91 lines
2.4 KiB
C

/*
* Minimalist driver for a generic PCI-to-EISA bridge.
*
* (C) 2003 Marc Zyngier <maz@wild-wind.fr.eu.org>
*
* This code is released under the GPL version 2.
*
* Ivan Kokshaysky <ink@jurassic.park.msu.ru> :
* Generalisation from i82375 to PCI_CLASS_BRIDGE_EISA.
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/eisa.h>
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/init.h>
/* There is only *one* pci_eisa device per machine, right ? */
static struct eisa_root_device pci_eisa_root;
static int __init pci_eisa_init(struct pci_dev *pdev)
{
int rc, i;
struct resource *res, *bus_res = NULL;
if ((rc = pci_enable_device (pdev))) {
printk (KERN_ERR "pci_eisa : Could not enable device %s\n",
pci_name(pdev));
return rc;
}
/*
* The Intel 82375 PCI-EISA bridge is a subtractive-decode PCI
* device, so the resources available on EISA are the same as those
* available on the 82375 bus. This works the same as a PCI-PCI
* bridge in subtractive-decode mode (see pci_read_bridge_bases()).
* We assume other PCI-EISA bridges are similar.
*
* eisa_root_register() can only deal with a single io port resource,
* so we use the first valid io port resource.
*/
pci_bus_for_each_resource(pdev->bus, res, i)
if (res && (res->flags & IORESOURCE_IO)) {
bus_res = res;
break;
}
if (!bus_res) {
dev_err(&pdev->dev, "No resources available\n");
return -1;
}
pci_eisa_root.dev = &pdev->dev;
pci_eisa_root.res = bus_res;
pci_eisa_root.bus_base_addr = bus_res->start;
pci_eisa_root.slots = EISA_MAX_SLOTS;
pci_eisa_root.dma_mask = pdev->dma_mask;
dev_set_drvdata(pci_eisa_root.dev, &pci_eisa_root);
if (eisa_root_register (&pci_eisa_root)) {
printk (KERN_ERR "pci_eisa : Could not register EISA root\n");
return -1;
}
return 0;
}
/*
* We have to call pci_eisa_init_early() before pnpacpi_init()/isapnp_init().
* Otherwise pnp resource will get enabled early and could prevent eisa
* to be initialized.
* Also need to make sure pci_eisa_init_early() is called after
* x86/pci_subsys_init().
* So need to use subsys_initcall_sync with it.
*/
static int __init pci_eisa_init_early(void)
{
struct pci_dev *dev = NULL;
int ret;
for_each_pci_dev(dev)
if ((dev->class >> 8) == PCI_CLASS_BRIDGE_EISA) {
ret = pci_eisa_init(dev);
if (ret)
return ret;
}
return 0;
}
subsys_initcall_sync(pci_eisa_init_early);