From 32a9a682bef2f6fce7026bd94d1ce20028b0e52d Mon Sep 17 00:00:00 2001 From: Yuji Shimada Date: Mon, 16 Mar 2009 17:13:39 +0900 Subject: PCI: allow assignment of memory resources with a specified alignment This patch allows memory resources to be assigned with a specified alignment at boot-time or run-time. The patch is useful when we use PCI pass-through, because page-aligned memory resources are required to securely share PCI resources with guest drivers. If you want to assign the resource at boot time, please set "pci=resource_alignment=" boot parameter. This is format of "pci=resource_alignment=" boot parameter: [@][:]:.[; ...] Specifies alignment and device to reassign aligned memory resources. If is not specified, PAGE_SIZE is used as alignment. PCI-PCI bridge can be specified, if resource windows need to be expanded. This is example: pci=resource_alignment=20@07:00.0;18@0f:00.0;00:1d.7 If you want to assign the resource at run-time, please set "/sys/bus/pci/resource_alignment" file, and hot-remove the device and hot-add the device. For this purpose, fakephp or PCI hotplug interfaces can be used. The format of "/sys/bus/pci/resource_alignment" file is the same with boot parameter. You can use "," instead of ";". For example: # cd /sys/bus/pci # echo -n 20@12:00.0 > resource_alignment # echo 1 > devices/0000:12:00.0/remove # echo 1 > rescan Reviewed-by: Alex Chiang Reviewed-by: Yu Zhao Signed-off-by: Yuji Shimada Signed-off-by: Jesse Barnes --- drivers/pci/setup-res.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'drivers/pci/setup-res.c') diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c index 32e8d88a4619..3039fcb86afc 100644 --- a/drivers/pci/setup-res.c +++ b/drivers/pci/setup-res.c @@ -120,6 +120,21 @@ int pci_claim_resource(struct pci_dev *dev, int resource) return err; } +#ifdef CONFIG_PCI_QUIRKS +void pci_disable_bridge_window(struct pci_dev *dev) +{ + dev_dbg(&dev->dev, "Disabling bridge window.\n"); + + /* MMIO Base/Limit */ + pci_write_config_dword(dev, PCI_MEMORY_BASE, 0x0000fff0); + + /* Prefetchable MMIO Base/Limit */ + pci_write_config_dword(dev, PCI_PREF_LIMIT_UPPER32, 0); + pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0); + pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff); +} +#endif /* CONFIG_PCI_QUIRKS */ + int pci_assign_resource(struct pci_dev *dev, int resno) { struct pci_bus *bus = dev->bus; -- cgit v1.2.3