linux/drivers/eisa/pci_eisa.c
Yinghai Lu c5fb301ae8 EISA/PCI: Init EISA early, before PNP
Matthew reported kernels fail the pci_eisa probe and are later successful
with the virtual_eisa_root_init force probe without slot0.

The reason for that is: PNP probing is before pci_eisa_init gets called
as pci_eisa_init is called via pci_driver.

pnp 00:0f has 0xc80 - 0xc84 reserved.
[    9.700409] pnp 00:0f: [io  0x0c80-0x0c84]

so eisa_probe will fail from pci_eisa_init
				==>eisa_root_register
					==>eisa_probe path.
as force_probe is not set in pci_eisa_root, it will bail early when
slot0 is not probed and initialized.

Try to use subsys_initcall_sync instead, and will keep following sequence:
	pci_subsys_init
	pci_eisa_init_early
	pnpacpi_init/isapnp_init

After this patch EISA can be initialized properly, and PNP overlapping
resource will not be reserved.
[   10.104434] system 00:0f: [io  0x0c80-0x0c84] could not be reserved

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>
Cc: stable@vger.kernel.org
2013-04-01 12:02:05 -06:00

92 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);