[ 21/64] EISA/PCI: Init EISA early, before PNP

From: Greg Kroah-Hartman
Date: Wed Apr 10 2013 - 19:12:37 EST


3.8-stable review patch. If anyone has any objections, please let me know.

------------------

From: Yinghai Lu <yinghai@xxxxxxxxxx>

commit c5fb301ae83bec6892e54984e6ec765c47df8e10 upstream.

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@xxxxxxxxxx>
Tested-by: Matthew Whitehead <mwhitehe@xxxxxxxxxx>
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/eisa/pci_eisa.c | 41 ++++++++++++++++++++++-------------------
1 file changed, 22 insertions(+), 19 deletions(-)

--- a/drivers/eisa/pci_eisa.c
+++ b/drivers/eisa/pci_eisa.c
@@ -19,8 +19,7 @@
/* 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,
- const struct pci_device_id *ent)
+static int __init pci_eisa_init(struct pci_dev *pdev)
{
int rc;

@@ -45,22 +44,26 @@ static int __init pci_eisa_init(struct p
return 0;
}

-static struct pci_device_id pci_eisa_pci_tbl[] = {
- { PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,
- PCI_CLASS_BRIDGE_EISA << 8, 0xffff00, 0 },
- { 0, }
-};
-
-static struct pci_driver __refdata pci_eisa_driver = {
- .name = "pci_eisa",
- .id_table = pci_eisa_pci_tbl,
- .probe = pci_eisa_init,
-};
-
-static int __init pci_eisa_init_module (void)
+/*
+ * 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)
{
- return pci_register_driver (&pci_eisa_driver);
-}
+ 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;
+ }

-device_initcall(pci_eisa_init_module);
-MODULE_DEVICE_TABLE(pci, pci_eisa_pci_tbl);
+ return 0;
+}
+subsys_initcall_sync(pci_eisa_init_early);


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