From: Matthew Wilcox Date: Mon, 11 Feb 2008 04:18:15 +0000 (-0500) Subject: Use proper abstractions in quirk_intel_irqbalance X-Git-Tag: v2.6.25-rc2~94 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9585ca02f8f9e844b64e7ff4d167ccc1390a99ab;p=linux-2.6 Use proper abstractions in quirk_intel_irqbalance Since we may not have a pci_dev for the device we need to access, we can't use pci_read_config_word. But raw_pci_read is an internal implementation detail; it's better to use the architected pci_bus_read_config_word interface. Using PCI_DEVFN instead of a mysterious constant helps reassure everyone that we really do intend to access device 8. [ Thanks to Grant Grundler for pointing out to me that this is exactly what the write immediately above this is doing -- enabling device 8 to respond to config space cycles. - Matthew Grant also says: "Can you also add a comment which points at the Intel documentation? The 'Intel E7320 Memory Controller Hub (MCH) Datasheet' at http://download.intel.com/design/chipsets/datashts/30300702.pdf Page 69 documents register F4h (DEVPRES1). And I just doubled checked that the 0xf4 register value is restored later in the quirk (obvious when you look at the code but not from the patch" so here it is. - Linus ] Signed-off-by: Matthew Wilcox Acked-by: Grant Grundler Signed-off-by: Linus Torvalds --- diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c index 1941482d4c..c47208fc59 100644 --- a/arch/x86/kernel/quirks.c +++ b/arch/x86/kernel/quirks.c @@ -11,7 +11,7 @@ static void __devinit quirk_intel_irqbalance(struct pci_dev *dev) { u8 config, rev; - u32 word; + u16 word; /* BIOS may enable hardware IRQ balancing for * E7520/E7320/E7525(revision ID 0x9 and below) @@ -26,8 +26,11 @@ static void __devinit quirk_intel_irqbalance(struct pci_dev *dev) pci_read_config_byte(dev, 0xf4, &config); pci_write_config_byte(dev, 0xf4, config|0x2); - /* read xTPR register */ - raw_pci_read(0, 0, 0x40, 0x4c, 2, &word); + /* + * read xTPR register. We may not have a pci_dev for device 8 + * because it might be hidden until the above write. + */ + pci_bus_read_config_word(dev->bus, PCI_DEVFN(8, 0), 0x4c, &word); if (!(word & (1 << 13))) { dev_info(&dev->dev, "Intel E7520/7320/7525 detected; "