[PATCH 13/40] PCI: Claim hw/fw allocated resources in hot add path.

From: Yinghai Lu
Date: Wed Sep 19 2012 - 15:04:05 EST


During testing remove/rescan root bus 00, found
[ 338.142574] bus: 'pci': really_probe: probing driver ata_piix with device 0000:00:01.1
[ 338.146788] ata_piix 0000:00:01.1: device not available (can't reserve [io 0x01f0-0x01f7])
[ 338.150565] ata_piix: probe of 0000:00:01.1 failed with error -22

because that fixed resource is not claimed from
arch/x86/pci/i386.c::pcibios_allocate_resources()
that is init path.

Try to claim those resources, so on the remove/rescan will still use old
resources.

It is some kind honoring HW/FW setting in the registers during hot add.
esp root-bus hot add is through acpi, BIOS have chance to set some register
for us.

-v2: add rom resource claiming.
-v3: separate __init removing to another patch, also
put pci_probe checking with caller from rom resource allocating

Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
---
arch/x86/pci/i386.c | 13 +++++++++++++
drivers/pci/bus.c | 2 ++
include/linux/pci.h | 1 +
3 files changed, 16 insertions(+), 0 deletions(-)

diff --git a/arch/x86/pci/i386.c b/arch/x86/pci/i386.c
index 1806e91..e0b7f30 100644
--- a/arch/x86/pci/i386.c
+++ b/arch/x86/pci/i386.c
@@ -352,6 +352,19 @@ static int __init pcibios_assign_resources(void)
return 0;
}

+void pcibios_resource_survey_bus(struct pci_bus *bus)
+{
+ dev_printk(KERN_DEBUG, &bus->dev, "Allocating resources\n");
+
+ pcibios_allocate_bus_resources(bus);
+
+ pcibios_allocate_resources(bus, 0);
+ pcibios_allocate_resources(bus, 1);
+
+ if (!(pci_probe & PCI_ASSIGN_ROMS))
+ pcibios_allocate_rom_resources(bus);
+}
+
void __init pcibios_resource_survey(void)
{
struct pci_bus *bus;
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 4b0970b..2882d01 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -154,6 +154,8 @@ pci_bus_alloc_resource(struct pci_bus *bus, struct resource *res,
return ret;
}

+void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
+
/**
* pci_bus_add_device - add a single device
* @dev: device to add
diff --git a/include/linux/pci.h b/include/linux/pci.h
index be1de01..ec25403 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -676,6 +676,7 @@ extern struct list_head pci_root_buses; /* list of all known PCI buses */
/* Some device drivers need know if pci is initiated */
extern int no_pci_devices(void);

+void pcibios_resource_survey_bus(struct pci_bus *bus);
void pcibios_fixup_bus(struct pci_bus *);
int __must_check pcibios_enable_device(struct pci_dev *, int mask);
/* Architecture specific versions may override this (weak) */
--
1.7.7

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